Datasheet Z8018933ASC, Z8018933FSC, Z8L18920ASC, Z8L18920FSC Datasheet (ZILOG)

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FEATURES

PRELIMINARY

RELIMINARY PRODUCT SPECIFICATION

Z80189/Z8L189

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Part CPU UART I/O Speed (MHz)

Z80189 S180* 16550 24 33 Z8L189 S180* 16550 24 20

■ Fully Static Z180™ MPU Core*

– On-Chip 1 MByte MMU – Two Enhanced UART Channels (up to 512 Kbps)† – Two Chain-Linked DMA Channels† – x 2 Clock Multiplier – Low-Power Consumption Modes – Two 16-Bit Timer/Counters – Clocked Serial I/O – On-Chip Wait State Generator (WSG) – On-Chip Interrupt Controller

On-Chip Clock Oscillator/Generator

–

■ 16550 Compatible MIMIC Interface

– 16 mA MIMIC Output Drive Capability

GENERAL DESCRIPTION

The Z80189/Z8L189 are cost-effective modem controllers that address a new generation of data pumps having the HDLC formatting feature. Data pumps of these types do not require an HDLC interface; therefore, the Z80189 does not need the ESCC™. The addition of the PC DMA Mailbox Registers allow DMA data transfer between the PC memory and the modem speaker/microphone CODEC. The Z80189 is a smart peripheral controller chip for modem (in particular V.34 applications), fax, voice messaging, and other communications applications.

The Z80189/Z8L189 consists of an enhanced Z8S180 microprocessor, a 16550 MIMIC with increased MIMIC drive capability for direct connection to the IBM PC, XT, AT bus, and 24 bits of parallel I/O. Current PC modem software compatibility can be maintained with the Z80189's ability to mimic the 16550 UART chip. The Z80180 core is the intelligent controller between the data pump and 16550 MIMIC interface when used in internal applications. This intelligent controller performs the data compression and error correction on outgoing and incoming data.

■ Com Port Decode

■ PC DMA Mailbox Registers

■ Host I/O Mailbox

■ Programmable Fixed /ROMCS and

/RAMCS Boundaries

■ 100-Pin QFP and VQFP Packages

■ 3.3 and 5.0-Volt Operating Ranges

■ 0°C to +70°C Temperature Range

Notes:

† Enhancements from the Discrete S180 device.

The integration of COM Port Decode circuitry to the Z80189 allows the MIMIC to be selected for a specific COM Port Address (PC COM Port Address 1-4). COM Port Decode circuitry is simplified by allowing the user to select the MIMIC COM Port addresses through software, in addition to eliminating the need for external circuitry required for COM Port Decode logic.

The PC DMA and I/O Mailbox Interface can be used to provide communication paths between the PC Host and the Z80189. These new communication paths can be used for voice, DTAD, or jumperless COM Port selection.

Notes:

All Signals with a preceding front slash, "/", are active Low, e.g.: B//W (WORD is active Low); /B/W (BYTE is active Low, only).

Power connections follow conventional descriptions below:

Connection Circuit Device

Power V

Ground GND V

DD SS

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PRELIMINARY

GENERAL DESCRIPTION (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

PC ISA BUS

Baud Rate

Generator

16550 MIMIC

Interface

COM Decoder

PC DMA

DMA & I/O

Interface

8-Bit Parallel

Port A

8-Bit Parallel

Port B

Enhanced S180 MPU

8-Bit Parallel

Port C

Figure 1. Z80189 Block Diagram

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PIN DESCRIPTION

/NMI

/RESET

/HDACK1//BUSREQ

PRELIMINARY

PHI

VSS

/RD

/WR

/M1

/IOCS2/E

EXTAL

HA4//WAIT

XTAL

HDRQ1//BUSACK

/MRD//MREQ

/IORQ

HA3//RFSH

/HALT

/HCS/HC1

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

HA2

HA1/RXA0

/INT0 /INT1/PC6 /INT2/PC7

ST A0 A1 A2 A3 A4

A8 A9

A10

A11

A12

VSS

A13 A14

A15

A16 A17

A18

VDD

A19

D0 D1 D2 D3

100

HA0 /HDDIS/TXA0

/HWR//CTS0 /HRD//DCD0

HINTR2 HAEN HA6

VDD HA7/IEI

/IOCS1/IEO VSS

HA8 PC4

100-Pin QFP

Z80189/Z8L189

PC0 PC1 /MWR/PC2 PC3 PC5 HD7/PA7

HD6/PA6 HD5/PA5 HD4/PA4 HD3/PA3 HD2/PA2

HD1/PA1 HD0/PA0 EV2 EV1

50454035

/ROMCS

/RAMCS

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PB0/TXS

PB1//CTS0

PB4/RXA0

PB3/TXA0

PB2//DCD0

PB5/TXA1

PB6/RXA1

VSS

PB7/RXS//CTS1

/HDACK0/CKA0//DREQ0

HINTR1/TOUT

HA9/CKA1//TEND0

HC2/CKS

HA5//DREQ1

VDD

HDRQ0//RTS0

Figure 2. Z80189/Z8L189 100-Lead QFP Pin Identification

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PIN DESCRIPTION (Continued)

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/HDDIS/TXA0

HA0

HA1/RXA0

HA2

/HCS/HC1

/HALT

HA3//RFSH

/IORQ

/MRD//MREQ

/IOCS2/E

/M1

/WR

/RD PHI

VSS

XTAL

EXTAL

HA4//WAIT

HDRQ1//BUSACK

/HDACK1//BUSREQ

/RESET

/NMI

/INT0 /INT1/PC6 /INT2/PC7

/HRD//DCD0

/HWR//CTS0

75 51

100

125

HINTR2

HAEN

HA6

VDD

HA7/IEI

/IOCS/IEO

VSS

HA8

PC0

PC1

PC4

Z80189/Z8L189

100-Pin VQFP

10 15 20

/MWR/PC2

PC3

PC5

6070 5565

HD7/PA7

HD6/PA6

HD5/PA5

HD4/PA4

HD3/PA3

HD2/PA2

HD1/PA1

HD0/PA0

EV2

EV1 /ROMCS /RAMCS HDRQ0/RTS0 VDD HA5//DREQ1 HC2/CKS

HINTR1/TOUT HA9/CKA1//TEND0

VSS /HDACK0/CKA0//DREQ0 PB7/RXS//CTS1 PB6/RXA1

PB5/TXA1 PB4/RXA0 PB3/TXA0 PB2//DCD0 PB1//CTS0

PB0/TXS D7 D6 D5 D4 D3 D2

A0A1A2

A3A4A5

A6A7A8

A11

A10

A12

A14

A15

A16

A17

VSS

A13

A18

VDD

A19

Figure 3. Z80189/Z8L189 100-Lead VQFP Pin Identification

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ABSOLUTE MAXIMUM RATINGS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Symbol Description Min Max Units

OPR

STG

Notes:

(*) Voltage on all pins with respect to GND.

Supply Voltage (*) –0.3 +7.0 V Input Voltage –0.3 VCC+0.3 V Operating Temp. 0 70 °C Storage Temp. –55 +150 °C

STANDARD TEST CONDITIONS

The DC Characteristics and capacitance sections below apply for the following standard test conditions, unless otherwise noted. All voltages are referenced to GND (0V). Positive current flows into the referenced pin (Test Load).

Available operating temperature range is:

S=0°C to 70°C

Voltage Supply Range:

+4.5V ≤ VCC ≤ +5.5V +3.0V ≤ VCC ≤ +3.6V

Stresses greater than those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; operation of the device at any condition above those indicated in the operational sections of these specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

= 2 mA

1.4 V

100 pF

All AC parameters assume a load capacitance of 50 pF. Add 10 ns delay for each 50 pF increase in load up to a maximum of 150 pF for the data bus and 100 pF for address and control lines. AC timing measurements are referenced to 1.5 volts (except for clock, which is referenced to the 10% and 90% points). Maximum capacitive load for PHI is 125 pF.

= 250 µA

Figure 4. Test Load Diagram

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

DC CHARACTERISTICS

Z80189 (V

= 5.0V ±10% or VCC = 3.3v ±10%, over specified temperature range unless otherwise noted.)

Symbol Parameter Min Typ Max Unit Condition

Z80189/Z8L189

IH1

Input H Voltage VCC –0.6 VCC +0.3 V RESET, EXTAL, NMI, INT0, INT1, INT2

IH2

Input H Voltage 2.0 VCC +0.3 V Except RESET, EXTAL, NMI, INT0, INT1, INT2

IL1

Input L Voltage –0.3 0.6 V RESET, EXTAL, NMI, INT0, INT1, INT2

IL2

Input L Voltage –0.3 0.8 V Except RESET, EXTAL, NMI, INT0, INT1, INT2

OH1

Output H Voltage V All outputs 2.4 V IOH = –200 µA

OH2

OL1

Output H PHI VCC –0.6 V I

= –200 µA

Output L Voltage 0.40 V IOL = 2.2 mA All outputs

OL2

Output L PHI 0.40 V IOL= 2.2 mA All MIMIC Outputs 2.4 V IOH = 16 mA,**

All MIMIC Outputs 0.4 V I

= 16 mA,**

All MIMIC Outputs 2.4 V IOH =8 mA,VCC= 3.3 V** All MIMIC Outputs 0.4 V I

=8 mA,VCC= 3.3 V**

Input Leakage 10 µAVIN = 0 to VCC 5 Current All Inputs Except XTAL, EXTAL

Tri-State Leakage Current 10 µAVIN = 0 to VCC 5

ICC* Power Dissipation* 18 30 mA f = 20 MHz, 3.3v

Normal Operation 80 120 mA f = 33 MHz, 5v

ICC* Power Dissipation* 1.8 3.6 mA f = 20 MHz, 3.3v

(System STOP Mode) 6 9 mA f = 33 MHz, 5v Power Dissipation 15 50 µA (Standby Mode)

Notes:

* VIH Min = VCC -1.0 V, V ** Total loading current in or out of the Z189 cannot exceed 150 mA from pins 41 to 70.

Max = 0.8 V (all output terminals are at no load).

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TIMING DIAGRAMS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Address

/WAIT

/MREQ

/IORQ

/RD

/WR

Opcode Fetch Cycle

I/O Write Cycle † I/O Read Cycle †

T1 T2 TW T3 T1 T2 TW T3 T1

1 6

20 19

13 28

26 and 26a

1129

/M1

Data

Data OUT

/RESET

Figure 5. CPU Timing

(Opcode Fetch Cycle, Memory Read/Write Cycle I/O Read/Write Cycle)

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TIMING DIAGRAMS (Continued)

/INTI

/NMI

/INTSCC

/M1 [1]

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/IORQ [1]

/Data IN [1]

/MREQ [2]

/RFSH [2]

/BUSREQ

/BUSACK

Address

Data /MREQ,

/RD, /WR,

/IORQ

4041 42

35 35

[3]

3736

3838

/HALT

Notes: [1] During /INT0 acknowledge cycle [2] During refresh cycle

[3] Output buffer is off at this point

Figure 6. CPU Timing

(/INT0 Acknowledge Cycle, Refresh Cycle, BUS RELEASE Mode

HALT Mode, SLEEP Mode, SYSTEM STOP Mode)

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TIMING DIAGRAMS (Continued)

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Address

/IROQ

/RD

/WR

I/O Read Cycle

T1 T2 TW T3 T1

CPU or DMA Read/Write Cycle (Only DMA Write Cycle for /TENDi)

T1 T2 Tw T3 T1

Figure 7. CPU Timing

I/O Write Cycle

T2 TW T3

/DREQi

(At level

sense)

/DREQi

(At edge

sence)

/TENDi

[1]

[2]

[4]

[3]

DMA Control Signals

[

1] tDRQS and tDRQH are specified for the rising edge of clock followed by T3. [2] tDRQS and tDRQH are specified for the rising edge of clock. [3] DMA cycle starts. [4] CPU cycle starts.

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Figure 8. DMA Control Signals

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TIMING DIAGRAMS (Continued)

T1 T2 Tw Tw T3

PRELIMINARY

49 50

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

1615

D7-D0

BUS RELEASE Mode

SLEEP Mode SYSTEM STOP Mode

Figure 9. E Clock Timing

(Memory Read/Write Cycle

I/O Read/Write Cycle)

5049

Figure 10. E Clock Timing

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TIMING DIAGRAMS (Continued)

T2 Tw T3 T1 T2

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

(Example:

I/O Read -

Opcode

Fetch)

(I/O Write)

Figure 11. E Clock Timing

(Minimum timing example

of PWEL and PWEH)

TOUT

Timer Data Reg = 0000H

Figure 12. Timer Output Timing

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TIMING DIAGRAMS (Continued)

SLP Instruction Fetch Next Opcode Fetch

T3 T1 T2 TS TS T1 T2

/INTi

/NMI

A18-A0

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/MREQ, /M1

/RD

/HALT

43 44

Figure 13. SLEEP Execution Cycle

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TIMING DIAGRAMS (Continued)

CSI/O Clock

Transmit Data

(Internal Clock)

Transmit Data

(External Clock)

Receive Data

(Internal Clock)

PRELIMINARY

56 56

5757

11 tcyc 11 tcyc

5958 5958

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Receive Data

(External Clock)

/MREQ

/RAMCS

11.5 tcyc

16.5 tcyc 16.5 tcyc

6160 60 61

Figure 14. CSI/O Receive/Transmit Timing

11.5 tcyc

/ROMCS

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Figure 15. /ROMCS and /RAMCS Timing

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TIMING DIAGRAMS (Continued)

T1 T2 TW T3 T1

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Address

/MREQ

/RD

/WR

Address Valid

Figure 16. /MWR and /MRD Timing

65 66

EXTAL VIL1

Figure 17. External Clock Rise Time and Fall Time

VIH1

VIL1

Figure 18. Input Rise and Fall Time

(Except EXTAL, /RESET)

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

AC CHARACTERISTICS

= 5V ±10% or VCC = 3.3V ±10%, over specified temperature range unless otherwise noted

33 MHz Characteristics Apply Only to 5V Operation.)

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Unit Notes

1 tcyc Clock Cycle Time 50 2000 33 2000 ns [1] 2 tCHW Clock H Pulse Width 15 10 ns [1] 3 tCLW Clock L Pulse Width 15 10 ns [1] 4 tcf Clock Fall Time 10 5 ns [1]

5 tcr Clock Rise Time 10 5 ns [1] 6 tAD /PHI to Address Valid 15 15 ns 7 tAS Address Valid to /MREQ, /IRQ 5 5 ns 8 tMED1 /PHI to /MREQ Delay 3 3 ns [3] 9 tRDD1 /PHI to /RD Delay (IOC=1) 25 15 ns

/ PHI to /RD Delay (IOC=0) 25 15 ns

10 tM1D1 /PHI to /M1 Delay 35 15 ns 11 tAH Address Hold Time from (MREQ, IOREQ, RD, WR) 5 5 ns 12 tMED2 /PHI to /MREQ Delay 25 15 ns 13 tRDD2 /PHI to /RD Delay 25 15 ns 14 tM1D2 /PHI to /M1 Delay 40 15 ns

15 tDRS Data Read Setup Time 10 10 ns [3] 16 tDRH Data Read Hold Time 0 0 ns 17 tSTD1 /PHI to /ST Delay 30 15 ns 18 tSTD2 /PHI to /ST Delay 30 15 ns 19 tWS WAIT Setup Time to /PHI 15 10 ns [2]

20 tWH WAIT Hold Time from /PHI 10 5 ns 21 tWDZ /PHI to Data Float Display 35 20 ns 22 tWRD1 /PHI to /WR Delay 25 15 ns 23 tWDD /PHI to Write Data Delay Time 25 15 ns 24 tWDS Write Data Setup Time to /WR 10 10 ns

25 tWRD2 /PHI to /WR Delay 25 15 ns 26 tWRP Write Pulse Width (Memory Write Cycle) 75 45 ns 26a tWRP Write Pulse Width (I/O Write Cycle) 130 70 ns 27 tWDH Write Data Hold Time from /WR 10 5 ns 28 tIOD /PHI to /IORQ Delay (IOC=1) 25 15 ns

/PHI to /IORQ Delay (IOC=0) 25 15 ns

29 tIOD2 /PHI to /IORQ Delay 25 15 ns 30 tIOD3 /M1 to /IORQ Delay 100 80 ns

31 tINTS /INT Setup Time to /PHI 20 15 ns 32 tINTH /INT Hold Time from /PHI 10 10 ns 33 tNMIW NMI Pulse Width 35 25 ns 34 tBRS BUSREQ Setup Time to /PHI 10 10 ns

35 tBRH BUSREQ Hold Time from /PHI 10 10 ns 36 tBAD1 /PHI to /BUSACK Delay 25 15 ns 37 tBAD2 /PHI to /BUSACK Delay 25 15 ns 38 tBZD /PHI to Bus Floating Delay Time 40 30 ns 39 tMEWH MREQ Pulse Width (High) 35 25 ns 40 tMEWL MREQ Pulse Width (Low) 35 25 ns

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

AC CHARACTERISTICS (Continued)

Z80189/Z8L189

= 5V ±10% or VCC = 3.3V ±10%, over specified temperature range unless otherwise noted

33 MHz Characteristics Apply Only to 5V Operation.)

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Unit Notes

41 tRFD1 /PHI to /RFSH Delay 20 15 ns 42 tRFD2 /PHI to /RFSH Delay 20 15 ns 43 tHAD1 /PHI to /HALT Delay 15 15 ns 44 tHAD2 /PHI to /HALT Delay 15 15 ns

45 tDRQS DREQ Setup Time to /PHI 20 15 ns 46 tDRQH DREQ Hold Time from /PHI 20 15 ns 47 tTED1 /PHI to /TEND Delay 25 15 ns 48 tTED2 /PHI to /TEND Delay 25 15 ns 49 tED1 /PHI to /E Delay 30 15 ns

50 tED2 /PHI /or to /E Delay 30 15 ns 51 PWEH E Pulse Width (High) 25 20 ns 52 PWEL E Pulse Width (Low) 50 40 ns 53 tEr Enable Rise Time 10 10 ns 54 tEf Enable Fall Time 10 10 ns

55 tTOD /PHI to Timer Output Delay 75 50 ns 56 tSTDI CSI/O Transmit Data Delay (Internal Clock Operation) 75 60 ns 57 tSTDE CSI/O Transmit Data Delay (External Clock Operation) 7.5 tcyc+75 7.5 tcyc+60 ns 58 tSRSI CSI/O Receive Data Setup Time (Internal Clock Operation) 1 1 phi cycles 59 tSRHI CSI/O Receive Data Hold Time (Internal Clock Operation) 1 1 phi cycles

60 tSRSE CSI/O Receive Data Setup Time (External Clock Operation) 1 1 phi cycles 61 tSRHE CSI/O Receive Data Hold Time (External Clock Operation) 1 1 phi cycles 62 tRES RESET Setup Time to /PHI 40 25 ns 63 tREH RESET Hold Time from /PHI 25 15 ns 64 tOSC Oscillator Stabilization Time 20 20 ns

65 tEXr External Clock Rise Time (EXTAL) 10 5 ns 66 tEXf External Clock Fall Time (EXTAL) 10 5 ns 67 tRr Reset Rise Time 50 50 ms [2] 68 tRf Reset Fall Time 50 50 ms [2] 69 tIr Input Rise Time (Except EXTAL, RESET) 50 50 ns [2] 70 tIf Input Fall Time (Except EXTAL, RESET) 50 50 ns [2] 71 tdCS MREQ Valid to RAMCS and ROMCS Valid Delay 5 5 ns [3]

Notes:

[1] tcyc = tCHW + tCLW + tcf + tcr. [2] If the rise and fall times are greater than the specified maximums, other specifications will not be met. [3] SL1832 is test screened such that specifications 8, 15, and 71 are tested to 18 ns (Tmeol + Tors + Trlcs = 18 ns).

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PRELIMINARY

AC CHARACTERISTICS (Continued)

Read/Write External Bus Master Timing

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Address

/IORQ

/RD

Data

/WR

A7-A0

Data Out

Data

Data In

Figure 19. Read/Write External Bus Master Timing

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

AC CHARACTERISTICS (Continued)

Read/Write External Bus Master Timing

Table 1. External Bus Master Timing

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Unit Notes

1 TsA(wf)(rf) Address to WR or RD Fall Time 20 20 ns 2 TsIO(wf)(rf) IORQ Fall to WR or RD Fall Time 20 20 ns 3 Th Data Hold Time (from WR Rise) 0 0 ns 4 TdRD(DO) RD Fall to Data Out Delay 35 35 ns 5 TdRIr(DOz) RD, IORQ Rise to Data Float Time 0 0 ns

6 TsDI(WRf) Data In to WR Fall Setup Time 20 20 ns 7 TsA(IORQf) Address to IORQ Fall Setup Time 35 35 ns 8 TsA(RDf) Address to RD Fall Setup Time 35 35 ns 9 TsA(WRf) Address to WR Fall Setup Time 35 35 ns

Table 2. 16550 MIMIC Timing

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Unit Notes

1 TsAR Address Setup to HRD Fall Time 30 30 ns 2 TsCSR Address Setup to CS Fall Time 30 30 ns 3 TsAW Address Setup to HWR Fall Time 30 30 ns 4 TsCSW HCS Setup to HWR Fall Time 30 30 ns 5 tAh Address Hold Time 20 20 ns 6 tCSh HCS Hold Time 20 20 ns

7 tDs Data Setup Time 30 30 ns 8 tDh Data Hold Time 30 30 ns 9 tWc Write Cycle Delay 2.5 2.5 phi cycles

10 tRvD Delay from HRD Fall to Data Valid 125 125 ns 11 tHz HRD Rise to Data Float Delay 100 100 ns 12 tRc Read Cycle Delay 125 125 ns

13 tRDD HRD Toggle to Driver Enable/Disable 60 60 ns 14 tSINT Delay fromwr RBR Reg. to Assert HINTR 2.0 2.0 phi cycles 15 tRINT Delay from /HRD of RBR to Deassert HINTR 2.0 2.0 phi cycles 16 tHR Delay from /WR THR to Reset HINTR 2.5 2.5 phi cycles 17 TSTI Delay from MPU /RD of THR to Assert HINTR 2.0 2.0 phi cycles 18 TIR Delay from /RD to Reset Interrupt 75 75 ns

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16550 MIMIC TIMING

/HCS

PRELIMINARY

ValidHA2, HA1, HA0

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/HRD

/HWR

Figure 20. PC Host /RD /WR Timing

Table 3. PC Host /RD /WR Timing Table

No Symbol Parameter Min Max Min Max Units

1 TsAR H Address to/HRD Fall Setup 30 30 ns 2 tsCSR /HCS to /HRD Fall Setup 30 30 ns 3 tsAW H Address to /HWR Fall Setup 30 30 ns 4 tsCSW /HCS to /HRD Fall Setup 30 30 ns 5 tAh H Address from /HRD /HWR Hold 20 20 ns 6 tCSh /HCS from /HRD /HWR Hold 20 20 ns

4 5

Z80L189-20 MHz Z80189-33 MHz

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16550 MIMIC TIMING (Continued)

HAEN

PRELIMINARY

Valid/HA3 - /HA9

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/HRD

/HWR

Figure 21. Com Port Decode Mode

PC Host /RD /WR Timing

Table 4. Com Port Decode Mode

PC Host /RD /WR Timing Table

No Symbol Parameter Min Max Min Max Units

4 5

Z8L189-20 MHz Z80189-33 MHz

1 tsAR H Address to/HRD Fall Setup 30 30 ns 2 tsCSR /HCS to /HRD Fall Setup 30 30 ns 3 tsAW H Address to /HWR Fall Setup 30 30 ns 4 tsCSW /HCS to /HRD Fall Setup 30 30 ns 5 tAh H Address from /HRD /HWR Hold 20 20 ns 6 tCSh /HCS from /HRD /HWR Hold 20 20 ns

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16550 MIMIC TIMING (Continued)

/HWR

PRELIMINARY

ValidHD7-HD0

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Figure 22. Data Setup and Hold, Output Delay, Write Cycle

ValidHD7-HD0

/HRD

Figure 23. Data Setup and Hold, Output Delay, Read Cycle

Table 5. Data Setup and Hold, Output Delay, Read Cycle Table

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

7 tDs Data In to /HWR Rise Setup 30 30 ns 8 tDh Data In from /HWR Rise Hold 30 30 ns 9 tWc Write Cycle Delay 2.5 2.5 phi cycles 10 tRvd /HRD Fall to Data Out Valid Delay 125 125 ns 11 THz /HRD Rise to Data Out Float Delay 100 100 ns 12 tRc Read Cycle Delay 2.5 2.5 phi cycles

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

16550 MIMIC TIMING (Continued)

/HRD

/HDDIS

Figure 24. Driver Enable Timing

Table 6. Driver Enable Timing Table

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

Z80189/Z8L189

13 tRDD /HRD to Driver

Enable/Disable 60 60 ns

/WR (MPU) RBR

HINTR (Trigger Level)

HINTR (Line Status RDR

/HRD LSR

/HRD RBR

Figure 25. Interrupt Timing RCVR FIFO

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

16550 MIMIC TIMING (Continued)

Table 7. Interrupt Timing RCVR FIFO Table

Z8L189-20 MHz Z80189-33 MHz Units

No Sym Parameter Min Max Min Max

14 tSINT Delay from Stop to Set 2 2 phi cycles

Interrupt

15 tRINT Delay from /HRD

(RD RBR or RD LSR) 2 2 phi cycles to Reset Interrupt

/RD (MPU) TxFIFO

Z80189/Z8L189

HINTR THRE

/WR (Host) THR

/RD (Host) 11R

Figure 26. Interrupt Timing Transmitter FIFO

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

16550 MIMIC TIMING (Continued)

Table 8. Interrupt Timing Transmitter FIFO Table

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

16 tHR Delay from /WR 2.5 2.5 phi cycles

(WR THR) to Reset Interrupt

17 TSTI Delay from Stop to 2 2 phi cycles

Interrupt (THRE)

18 TIR Delay from /RD to 2.5 2.5 phi cycles

Reset Interrupt

Table 9. I/O Port Timing Table

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

Z80189/Z8L189

1 TsPIA(WR) Data Setup Time to (Port) WR Fall 20 20 ns 2 TdWR(PIA) Data Valid Delay from WR Rise 60 60 ns

/WR

Port

Port (Output)

1 2 1 2

Port Output Data 1 (Out) Port Output Data 2 (Out)

Figure 27. I/O Port Timing Diagram

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

PC DMA TIMING

Table 10. PC DMA Mailbox Timing

PD DMA Write: Memory-Read, I/O Write DMA Bus Cycle

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

1 tACKWh /HDACK Active Hold 144 144 ns

/HWR Inactive

2 tWRs /HDACK Active to 301 301 ns

/HWR Active

3 tWR /HWR Active to 454 454 ns

Inactive

4 tvWR Data Valid to /HWR 133 133 ns

Inactive

5 tDWRh Write Data Valid Hold 25 25 ns

from /HWR Inactive

Table 11. PC DMA Mailbox Timing

PD DMA Read: I/O-Read, Memory-Write DMA Bus Cycle

Z8L189-20 MHz Z80189-33 MHz

No Sym Parameter Min Max Min Max Units

1 tACKRh /HDACK Active Hold 89 89 ns

/HRD Inactive

2 tRDs /HDACK Active to 62 62 ns

/HRD Active

3 tRD /HRD Active to 749 749 ns

Inactive

4 tvRD Data Valid from /HRD 215 215 ns

Active

5 tDRDh Read Data Valid Hold 0 0 ns

from /HRD Inactive

6 tDZ Data Float from /HRD 50 50 ns

Inactive

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PC DMA TIMING DIAGRAMS

PC Clock

Internal HDRQR

HDRQ

/AEN

/HDACK

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

(1)

/HWR

HD [0:7] Valid

PC Clock

Internal HDRQR

HDRQ

(1) The HDRQ will not fall inactive until it ses the falling edge of /HWR during the /HDACK cycle.

Figure 28. PC DMA Write: Memory-Read, I/O Write

DMA Bus Cycle on PC AT Bus

(1)

/AEN

/HDACK

/HRD

HD [0:7] Valid

(1) The HDRQ will not fall inactive until it sees the falling edge of /HRD during the /HDACK cycle.

Figure 29. PC DMA Read: I/O-Read, Memory-Write

DMA Bus Cycle on PC AT Bus

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PIN DESCRIPTION

CPU Signals

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

A19-A0. Address Bus (Input/Output, active High, tri-state).

A0-A19 form a 20-bit address bus. The Address Bus provides the address for memory data bus exchanges, up to 1 Mbyte, and I/O data bus exchanges, up to 64K. The address bus enters a high impedance state during reset and external bus acknowledge cycles, as well as during SLEEP and HALT states. This bus is an input when the external bus master is accessing the on-chip peripherals.

D7-D0. Data Bus (Bidirectional, active High, tri-state). D0D7 constitute an 8-bit bidirectional data bus, used for the transfer of information to and from I/O and memory devices. The data bus enters the high impedance state during reset and external bus acknowledge cycles, as well as during SLEEP and HALT states.

/RD. Read (Input/Output, active Low, tri-state). /RD indicates that the CPU wants to read data from memory or an I/O device. The addressed I/O or memory device should use this signal to gate data onto the CPU data bus.

/WR. Write (Output, active Low, tri-state). /WR indicates that the CPU data bus holds valid data to be stored at the addressed I/O or memory location.

/IORQ. I/O Request (Input/Output, active Low, tri-state). /IORQ indicates that the address bus contains a valid I/O address for an I/O read or I/O write operation. /IORQ is also generated, along with /M1, during the acknowledgment of the /INT0 input signal to indicate that an interrupt response vector can be placed onto the data bus.

/M1. Machine Cycle 1 (Input/Output, active Low). Together with /MREQ, /M1 indicates that the current cycle is the opcode fetch cycle of an instruction execution. Together with /IORQ, /M1 indicates that the current cycle is for an interrupt acknowledge. It is also used with the /HALT and ST signal to decode status of the CPU machine cycle.

/MREQ. Memory Request (Input/Output, active Low, tristate). /MREQ indicates that the address bus holds a valid address for a memory read or memory write operation.

/WAIT. (Input, active Low). /WAIT indicates to the MPU that the addressed memory or I/O devices are not ready for a data transfer. This input is used to induce additional clock cycles into the current machine cycle. The /WAIT input is sampled on the falling edge of t2 (and subsequent wait states). If the input is sampled low, then additional wait states are inserted until the /WAIT input is sampled high, at which time execution will continue.

/HALT. Halt/Sleep Status (Output, active Low). This output is asserted after the CPU has executed either the HALT or SLP instruction, and is waiting for either non-maskable or maskable interrupt before operation can resume. It is also used with the /M1 and ST signals to decode status of the CPU machine cycle. On exit of Halt/Sleep, the first instruction fetch is delayed 16 clock cycles after the /HALT pin goes high.

/BUSACK. Bus Acknowledge (Output, active Low tri-state). /BUSACK indicates to the requesting device, the MPU address and data bus, and some control signals, have entered their high-impedance state.

/BUSREQ. Bus Request (Input, active Low). This input is used by external devices (such as DMA controllers) to request access to the system bus. This request has a higher priority than /NMI and is always recognized at the end of the current machine cycle. This signal will stop the CPU from executing further instructions and places the address and data buses, and other control signals, into the high impedance state.

/NMI. Non-maskable interrupt (Input, negative edge triggered). /NMI has a higher priority than /INT and is always recognized at the end of an instruction, regardless of the state of the interrupt enable flip-flops. This signal forces CPU execution to continue at location 0066H.

/INT0. Maskable Interrupt Request 0 (Input, active Low). This signal is generated by external I/O devices. The CPU will honor this request at the end of the current instruction cycle as long as the /NMI and /BUSREQ signals are inactive. The CPU acknowledges this interrupt request with an interrupt acknowledge cycle. During this cycle, both the /M1 and /IORQ signals will become active.

/INT1, /INT2. Maskable Interrupt Requests 1 and 2 (inputs, active Low). This signal is generated by external I/O devices. The CPU will honor these requests at the end of the current instruction cycle as long as the /NMI, /BUSREQ, and /INT0 signals are inactive. The CPU will acknowledge these interrupt requests with an interrupt acknowledge cycle. Unlike the acknowledgment for /INT0, during this cycle neither the /M1 or /IORQ signals will become active. These pins may be programmed to provide active low level, rising or falling edge interrupts. The level of the external /INT1 and /INT2 pins may be read through bits PC6 and PC7 of parallel port C.

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PIN DESCRIPTION (Continued)

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/RFSH. Refresh (Output, active Low, tri-state). Together

with /MREQ,/RFSH indicates that the current CPU machine cycle and the contents of the address bus should be used for refresh of dynamic memories. The low order 8 bits of the address bus (A7-A0) contain the refresh address.

/MRD. Memory Read (Output, active Low, tri-state). /MRD is active when both the internal /MREQ and /RD signals are active.

/MWR. Memory write (output, active Low, tri-state). /MWR is active when both the internal /MREQ and /WR signals are active.

Z180™ MPU UART and SIO Signals

CKA0, CKA1. Asynchronous Clock 0 and 1 (Bidirectional, active High). When in output mode, these pins are the transmit and receive clock outputs from the ASCI baud rate generators. When in input mode, these pins serve as the external clock inputs for the ASCI baud rate generators.

CKS. Serial Clock (Bidirectional, active High). This line is the clock for the CSIO channel.

/DCD0. Data Carrier Detect 0 (Input, active Low). This is a programmable modem control signal for ASCI channel 0.

/RTS0. Request to Send 0 (Output, active Low, tri-state). This is a programmable modem control signal for ASCI channel 0.

/CTS0/CTS1. Clear to Send 0 (Input, active Low). This line is a modem control signal for the ASCI channel 0 and 1.

Z180™ MPU DMA Signals

/TEND0. Transfer End 0 (outputs, active Low). This output is asserted active during the last write cycle of a DMA operation. It is used to indicate the end of the block transfer.

/DREQ0, /DREQ1. DMA request 0 and 1 (Input, active Low). /DREQ is used to request a DMA transfer from one of the on-chip DMA channels. The DMA channels monitor these inputs to determine when an external device is ready for a read or write operation. These inputs can be programmed to be either level or edge sensed.

Z180™ MPU Timer Signals

. Timer Out (Output, active High). T

OUT

output from PRT channel 1. This line is multiplexed with HINTR1 of the 16550 MIMIC.

is the pulse

OUT

16550 MIMIC Interface Signals

HD7-HD0. Host Data Bus (Input/Output, tri-state). In Z80189, the host data bus is used to communicate between the 16550 MIMIC interface and the PC/XT/AT. It is multiplexed with the PA7-PA0 of parallel port A.

/HDDIS. Host Driver Disable (Output, active Low). In Z80189, this signal goes low whenever the PC/XT/AT is reading data from the 16550 MIMIC interface. The /HDDIS pin should also go active low on each PC DMA read cycle.

HA2-HA0. Host Address (Input). In Z80189, these pins are the address inputs to the 16550 MIMIC interface. This address determines which register the PC/XT/AT accesses.

TXA0. Transmit Data 0 (Output, active High). This signal is the transmitted data from the ASCI channel 0.

TXS. Clocked Serial Transmit Data (Output, active High). This line is the transmitted data from the CSIO channel.

RXA0. Receive Data 0 (Input, active High). This signal is the receive data to ASCI channel 0.

RXS. Clocked Serial Receive Data (Input, active High). This line is the receiver data for the CSIO channel.

RXA1. Received Data ASCI Channel 1.

TXA1. Transmitted Data ASCI Channel 1.

HA9-HA3, HAEN. Host COM Port Decode Address (Input). In Z80189, these pins are multiplexed when COM Port Decode is enabled (default). These pins are used to provide internal MIMIC Enable when HA9-HA3 match the programmed MIMIC address field. HAEN is also used to access the PC DMA Mailbox registers.

/HCS. Host Chip Select (Input, active Low). In Z80189, this input is used by the PC/XT/AT to select the 16550 MIMIC interface for an access. The /HCS input is disabled when using the internal COM Port Decoder. When setting the /HCS Force bit in the CDR register, the /HCS output is asserted when HA3-HA9 is within the boundaries programmed by bits 3-4 of the CDR register and /HRD or /HWR is asserted. /HCS is NOT asserted for PC DMA Mailbox accesses.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/HWR. Host Write (Input, active Low). In Z80189, this input

is used by the PC/XT/AT to signal the 16550 MIMIC interface that a write operation is taking place.

/HRD. Host Read (Input, active Low). In Z80189, this input is used by the PC/XT/AT to signal the 16550 MIMIC interface that a read operation is taking place.

HINTR1, HINTR2. Host Interrupt (Output, active High tristate). In Z80189, this output is used by the 16550 MIMIC interface to signal the PC/XT/AT that an interrupt is pending. In Z80189 COM Port Decode mode, the MIMIC interrupt request can be routed to either HINTR1 or 2 depending on the COM Port Decode selected. The deselected HINTR line will be forced to tri-state, while the selected HINTR will follow what is programmed in the MIMIC Master Control Register.

HC1, HC2. Host COM Select Pin 1&2 (Input). HC1 and HC2 are general-purpose inputs that can be used for COM Port selection. The status of these pins are read by use of the CDR register. The status of these pins can be used by firmware to select the appropriate COM Port address decode range.

PC7-PC0. Parallel Port C (Input/Output). These lines can be configured as inputs or outputs on a bit by bit basis for bits PC5-PC0. Bits PC7 and PC6 are input only and read the level of the external /INT2 and /INT1 pins. When /INT2 and/or /INT1 are in edge capture mode writing a ‘1’ to the respective PC7, PC6 bit clears the interrupt capture latch. Writing a ‘0’ has no effect.

Emulation Signals

EV1, EV2. Emulation Select (Input). These two pins determine the emulation mode the Z180 MPU is in. They are as follows:

EV2 EV1

Mode 0 0 0 Normal mode, on-chip Z180 bus

master. Mode 1 0 1 Emulation Adapter Mode Mode 2 1 0 Emulator Probe Mode Mode 3 1 1 Reserved

System Control Signals

PC DMA Mailbox Signals

/HDACK0, /HDACK1. Host DMA Acknowledge (Input, active Low). This input signal indicates to the Z80189 that the PC DMA controller has acknowledged the request and will begin data transfer. /HDACK0 is multiplexed with /CKA0 and /DREQ0. /HDACK1 is multiplexed with /BUSREQ.

HDRQ0, HDRQ1. Host DMA Request (output, active high, tri-state). This output requests to the PC DMA controller that the Z80189 is ready for a DMA data transfer. HDRQ is multiplexed with /RTS0. HDRQ1 is multiplexed with /BUSACK.

Parallel Ports

PA7-PA0. Parallel Port A (Input/Output). These lines can be configured as inputs or outputs on a bit-by-bit basis when the Z80189 is operated in mode 0.

PB7-PB0. Parallel Port B (Input/Output). These lines can be configured as inputs or outputs on a bit-by-bit basis when the port function is selected in the System Configuration register.

ST. Status (Output, active High). This signal is used with the M1 and /HALT output to decode the status of the CPU machine cycle.

/RESET. Reset Signal (Input, Active Low). /RESET signal is used for initializing the MPU and other devices in the system. It must be kept in the active state for a period of at least 6 system clock cycles.

IEI. Interrupt Enable Signal (Input, active High). IEI is used with the IEO to form a priority daisy chain when there is more than one interrupt driven peripheral.

IE0. Interrupt Enable Output Signal (Output, active High). In the daisy-chain interrupt control, IEO controls the interrupt of external peripherals. IEO is active when IEI is “1” and the CPU is not servicing an interrupt from the on-chip peripherals. This pin is multiplexed with /IOCS1.

/IOCS1. I/O Chip Select 1 (output, active Low) is an auxiliary chip select that decodes A7, A6, /IORQ, /M1 and effectively decodes the address space XX80 to XXBF for I/O transactions. A15 through A8 are not decoded so that the chip select is active in all pages of I/O address space. The /IOCS1 function is the default on power on or reset condition and is changed by programming bit 2 in the Interrupt Edge/Pin Mux Register.

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System Control Signals (Continued)

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

/IOCS2. I/O Chip Select 2 (output, active Low) This pin is

a secondary peripheral I/O chip select. This pin is active for I/O accesses between XXC0H to XXC7H or XXC8H to XXCFH (programmable by bit 1 of the IOBRG register).

/RAMCS. RAM Chip Select (Output, active Low). Signal used to access RAM based upon the address and the RAMLBR and RAMUBR registers.

/ROMCS. ROM Chip Select (Output, active Low). Signal used to access ROM based upon the address and the ROMBR register.

XTAL. Crystal (Output, active High). Crystal oscillator connection. This pin should be left open if an external clock

PIN MULTIPLEXING

To allow for COM Port decode and omission of ESCC core, Pin Multiplexing is changed with respect to the Z182.

ESCC CH.A pins will be replaced by COM Decode and ASCI CH.A pins as follows:

RxDA → HA6 /TRxCA → HAEN TxDA → HINTR2 DCDB → /HRD//DCD0 /CTSB → /HWR//CTS0

is used instead of a crystal. The oscillator input is not a TTL level (reference DC characteristics).

EXTAL. External Clock/Crystal (Input, active High). Crystal oscillator connections. An external clock can be input to the Z80189 on this pin when a crystal is not used. This input is Schmitt-triggered.

PHI. System Clock (Output, active High). The output is used as a reference clock of the MPU and the external system.

VCC. Power Supply. +5 Volts

VSS. Power Supply. 0 Volts

When COM decode bit is set (enabled during reset) the following pins become multiplexed as follows.

/RFSH → HA3 /WAIT → HA4 /DREQ1 → HA5 /HA6 → HA6 IEI → HA7 /HA8 → HA8 CKA1/TEND0 → HA9 /HAEN → HAEN

Note that ASCI channel 0 functions can be found in two places. These pins are ORed with ASCI channel 0 functions that are multiplexed with Port B (pins 35-39 QFP). /DCD0, /CTS0, RXA0 inputs will come from 78, 79, 81 (respectively) when Port B (0-4) is enabled. When MIMIC is disabled, /HDDIS pin doubles as TXA0 output. Note that /RTS0 has also been changed to pin 50.

These pins are selected such that they are all high-z inputs at power up to prevent any problems with connecting address lines directly to PC bus. Although, the COM decode multiplexing is enabled on power-up, the COM address decoding is disabled.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Table 12. Z80189 Pin-Out

Multiplexed Pin Descriptions Primary, Secondary Pin Functions

PIN # PIN # DEFAULT SECONDARY VQFP QFP FUNCTION FUNCTION CONTROL

14 ST 25 A0 36 A1 47 A2 58 A3 69 A4 710 A5 811 A6 912 A7 10 13 A8 11 14 A9 12 15 A10 13 16 A11 14 17 A12 15 18 V

16 19 A13 17 20 A14 18 21 A15 19 22 A16 20 23 A17 21 24 A18 22 25 V

23 26 A19 24 27 D0 25 28 D1 26 29 D2 27 30 D3 28 31 D4 29 32 D5 30 33 D6

Z80189/Z8L189

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GENERAL-PURPOSE EMBEDDED CONTROLLERS

PIN MULTIPLEXING (Continued)

Table 12. Z80189 Pin-Out (Continued)

Multiplexed Pin Descriptions Primary, Secondary Pin Functions

PIN # PIN # DEFAULT SECONDARY VQFP QFP FUNCTION FUNCTION CONTROL

31 34 D7 32 35 PB0 TXS System Config Reg bit 5 33 36 PB1 /CTS0 System Config Reg bit 5 34 37 PB2 /DCD0 System Config Reg bit 5 35 38 PB3 TXA0 System Config Reg bit 5 36 39 PB4 RXA0 System Config Reg bit 5 37 40 PB5 TXA1 System Config Reg bit 6 38 41 PB6 RXA1 System Config Reg bit 6 39 42 PB7 RXS//CTS1 System Config Reg bit 6 40 43 /HDACK0 CKA0//DREQ0 Host DMA Enable Reg bit 3

Z80189/Z8L189

41 44 V 42 45 HA9 CKA1//TENDO COM Decode Reg bit 0 43 46 HINTR1 T 44 47 HC2 CKS COM Decode Reg bit 0 45 48 HA5 /DREQ1 (4) 46 49 V 47 50 HDRQ0 /RTSO (6) Host DMA Enable Reg bit 3 48 51 /RAMCS 49 52 /ROMCS 50 53 EV1 51 54 EV2 52 55 HD0 PA0 Sys Config Reg bit 1 53 56 HD1 PA1 Sys Config Reg bit 1 54 57 HD2 PA2 Sys Config Reg bit 1 55 58 HD3 PA3 Sys Config Reg bit 1 56 59 HD4 PA4 Sys Config Reg bit 1 57 60 HD5 PA5 Sys Config Reg bit 1 58 61 HD6 PA6 Sys Config Reg bit 1 59 62 HD7 PA7 Sys Config Reg bit 1

OUT

System Config Reg bit 2

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PRELIMINARY

Z80189 MPU FUNCTIONAL DESCRIPTION

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Z80189 includes a Zilog Z8S180 MPU (Static Z80180 MPU). This allows software code compatibility with existing Z80/Z180 software code. The following is an overview of the major functional units of the Z80189.

Architecture

The Z80189 combines a high performance CPU core with a variety of system and I/O resources useful in a broad range of applications. The CPU core consists of four functional blocks:

■ Clock Generator

■ Bus State Controller (Dynamic Memory Refresh)

■ Memory Management Unit (MMU)

■ Central Processing Unit (CPU).

The integrated I/O resources make up the remaining functional blocks:

■ Direct Memory Access (DMA control—two channels)

■ Asynchronous Serial Communications Controller

(ASCI, two channels)

■ Programmable Reload Timers (PRT, two channels)

■ Clocked Serial I/O

■ 16550 Compatible MIMIC Interface

■ COM Port Decoder

■ PC DMA Mailbox Registers

■ Host I/O Mailbox Registers

Clock Generator. This logic generates the system clock from either an external crystal or clock input. The external clock is divided by two, or one if programmed, and is provided to both internal and external devices.

In addition, there is also a clock multiplier feature which doubles the internal clock frequency from that of the external clock input.

Bus State Controller. This logic performs all of the status and bus control activity associated with both the CPU and some on-chip peripherals. This includes wait state timing, reset cycles, DRAM refresh, and DMA bus exchanges.

Interrupt Controller. This logic monitors and prioritizes the variety of internal and external interrupts and traps to provide the correct responses from the CPU. To maintain compatibility with the Z80 CPU, three different interrupt modes are supported.

Memory Management Unit. The MMU allows the user to “map” the memory used by the CPU (logically only 64 Kbytes) into the 1 Mbyte addressing range supported by the Z80189. The organization of the MMU object code maintains compatibility with the Z80 CPU while offering access to an extended memory space. This is accomplished by using an effective “common area-banked area” scheme.

Central Processing Unit. The CPU is microcoded to provide a core that is object-code compatible with the Z80 CPU. It also provides a superset of the Z80 instruction set, including 8-bit multiply. This core has been modified to allow many of the instructions to execute in fewer clock cycles.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Table 12. Z80189 Pin-Out (Continued)

Multiplexed Pin Descriptions Primary, Secondary Pin Functions

PIN # PIN # DEFAULT SECONDARY VQFP QFP FUNCTION FUNCTION CONTROL

60 63 PC5 61 64 PC3 62 65 PC2 /MWR Int Edge/Pin Reg bit 3 63 66 PC1 64 67 PC0 65 68 PC4 66 69 HA8

Z80189/Z8L189

67 70 V

68 71 /IOCS1 IEO Int Edge/Pin reg bit 2 69 72 HA7 IEI (1) COM Decode reg bit 0 70 73 V

71 74 HA6 72 75 HAEN 73 76 HINTR2 74 77 /HRD /DCD0 (2) 75 78 /HWR /CTS0 (2) 76 79 /HDDIS TXA0 Sys Conf reg bit 1 77 80 HA0 78 81 HA1 RXA0 (2) 79 82 HA2 80 83 /HCS HC1 (3) 81 84 /HALT 82 85 HA3 /RFSH COM Decode reg bit 0 83 86 /IORQ 84 87 /MREQ /MRD Int Edge/Pin Reg bit 3 85 88 /IOCS2 E I/O brg reg bit 2 86 89 /M1 87 90 /WR 88 91 /RD 89 92 PHI 90 93 V

91 94 XTAL 92 95 EXTAL 93 96 HA4 /WAIT (5) COM Decode reg bit 0 94 97 HDRQ1 /BUSACK (6) Host DMA Enable Reg bit 2 95 98 /HDACK1 /BUSREQ (5) Host DMA Enable Reg bit 2 96 99 /RESET 97 100 /NMI 98 1 /INT0 99 2 /INT1 PC6 100 3 /INT2 PC7

All inputs feature an auto latch that assures that an unconnected input is seen as a logic high or logic low by both the

Notes:

1. IEI pulled high internally when default function is active

2. Pins also act as ASCI inputs only when Port B is enabled

3. MIMIC access is disabled until the system configuration register is written. /HCS can be forced to output the result of COM Port Decoder.

Z189 or any measurement device connected to the inputs. The auto latch will latch onto the previous state of input pin.

4. Pin simultaneously acts as input for both default and secondary functions.

5. /WAIT is pulled high internally when default function is active.

6. Upon power-up or reset, this pin is tri-state.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

TOUT

TxS

RxS

CKS

/WR

XTAL

Timing &

Clock

Generator

16-Bit

Programmable

Reload T imers

Clocked

Serial I/O

EXTAL

(2)

Port

/RD

/RESET

/IORQ

/MREQ

/M1

Bus State Control Interrupt

/WAIT

/HALT

CPU

DMACs

(2)

Asynchronous

SCI

(Channel 0)

/RFSH

/BUSACK

/BUSREQ

/NMI

/DREQ1

/TEND0

TxA0

CKA0/ /DREQ0 RxA0 /RTS0 /CTS0

/INT0

/INT1

/INT2

Address Bus (16-Bit)

MMU

A19-A0 D7-D0

Figure 30. Z189 MPU Block Diagram

Data Bus (8-Bit)

Asynchronous

SCI

(Channel 1)

/DCD0

TxA1

RxA1 /CTS1

/CKA1

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PRELIMINARY

Z80189 MPU FUNCTIONAL DESCRIPTION (Continued)

DMA Controller

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

DMA Controller. The DMA controller provides high-speed

transfers between memory and I/O devices. Transfer operations supported are memory-to-memory, memory to or from I/O, and I/O-to-I/O. Transfer modes supported are

Table 13. SAR18-16 and DAR18-16 I/O Device Encoding

SM1-0 SAR18-16 Source

11 000 ext (CKA0/DREQ) 11 001 ASCI0 Rx 11 010 ASCI1 Rx 11 011 ext (/DREQ1) 11 100 * 11 101 * 11 110 * 11 111 *

Asynchronous Serial Communications Interface (ASCI)

request, burst, and cycle steal. DMA transfers can access the full 1 Mbyte addressing range with a block length up to 64 Kbytes, and can cross over the 64 Kbytes boundaries.

DM1-0 DAR18-16 Destination

11 000 ext (CKA0//DREQ0) 11 001 ASCI0 Tx 11 010 ASCI1 Tx 11 011 ext (/DREQ1) 11 100 * 11 101 * 11 110 * 11 111 *

* Reserved do not use.

Reset DCD (ASCI0 with Auto Enables) and I/O Stop Mode Conditions

The ASCI logic provides two individual full-duplex UARTs. Each channel includes a programmable baud rate generator. The ASCI channels can also support a multiprocessor communications format. For ASCI0, up to three modem control signals and one clock signal can be pinned out, while ASCI1 has a data-only interface and 1 clock signal.

The receiver includes a 4-byte FIFO, plus a shift register as shown in Figure 31.

Error

Latches

4x4 Bit

Overrun

Error

FIFO

P F O B E E R K

Error Shift Register

Bit

During Reset and in I/O Stop state, and for ASCI0 if /DCD0 is auto-enabled and is High, an ASCI is forced to the following conditions:

■ FIFO Empty

■ All Error Bits Cleared (including those in the FIFO)

■ Receive Enable Cleared (cntla bit 6 = 0)

■ Transmit Enable Cleared (cntla bit 5 = 0).

If DCD is not auto-enabled, the /DCD pin has no effect on the FIFOs or enable bits.

Notes:

PE = Parity Error FE = Framing Error OR = Overrun BK = Break MP = Multiprocessor Bit

4-Byte

Data FIFO

RXA

Figure 31. ASCI Receiver

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GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

FIFO and Receiver Operation

The 4-byte Receive FIFO is used to buffer incoming data to reduce the incidence of overrun errors. When the RE bit is set in the CNTLA register, the RXA pin is monitored for a Low transition. One-half bit time after the Low transition of the RXA pin, the ASCI samples RXA again. If it has gone back to High, the ASCI ignores the previous Low transition and resumes looking for a new one, but if RXA is still Low, it considers this a start bit and proceeds to clock in the data based upon the internal baud rate generator or the external CKA pin. The number of data bits, parity, multiprocessor and stop bits are selected by the MOD2, MOD1, MOD0 and MP bits in the CNTLA and CNTLB registers. After the data has been received, the appropriate MP, parity and one stop bit are checked. Data and any errors are clocked into the FIFOs during the stop bit. Interrupts, Receive Data Register Full Flag, and DMA requests will also go active during this time.

Error Condition Handling

When the receiver places a data character in the Receive FIFO, it also places any associated error conditions in the error FIFO. The outputs of the error FIFO go to the set inputs of the software-accessible error latches. Writing a 0 to CNTLA EFR is the only way to clear these latches. In other words, when an error bit reaches the top of the FIFO, it sets an error latch. If the FIFO has more data and the software reads the next byte out of the FIFO, the error latch remains set, until the software writes a 0 to the EFR bit. The error bits are cumulative, so if additional errors are in the FIFO, they will set any upset error latches as they reach the top.

Overrun Error

An overrun occurs if the receive FIFO is full when the receiver has just assembled a byte in the shift register and is ready to transfer it to the FIFO. If this occurs, the overrun error bit associated with the previous byte in the FIFO is set. The latest data byte is not transferred from the shift register to the FIFO in this case, and is lost. Once an overrun occurs, the receiver does not place any further data in the FIFO, until the “last good byte received” has come to the top of the FIFO so that the Overrun latch is set, and software then clears the Overrun latch. Assembly of bytes continues in the shift register, but this data is ignored until the byte with the overrun error reaches the top of the FIFO and is cleared with a write of 0 to the EFR bit.

Break Detect

A Break is defined as a framing error with the data equal to all zeros. When a break occurs, the all-zero byte with its associated error bits are transferred to the FIFO, if it is not full. If the FIFO is full, an overrun is generated, but the break, framing error and data, are not transferred to the FIFO. Any time a break is detected, the receiver will not receive any more data until the RXA pin returns to a High state. If the channel is set in multiprocessor mode and the MPE bit of the CNTLA register is set to 1, then breaks, errors and data will be ignored unless the MP bit in the transmission is a 1. Note: The two conditions listed above could cause a break condition to be missed if the FIFO is full and the break occurs, or if the MP bit in the transmission is not a 1 with the conditions specified above.

Parity and Framing Errors

Parity and Framing Errors do not affect subsequent receiver operation.

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PRELIMINARY

Z80189 MPU FUNCTIONAL DESCRIPTION (Continued)

Baud Rate Generator

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Baud Rate Generator (BRG) has two modes. The first is the same as in the Z80180. The second is a 16-bit down counter that divides the processor clock by the value in a 16-bit time constant register, and is identical to the ESCC BRG. This allows a common baud rate of up to 512 Kbps to be selected. The BRG can also be disabled in favor of an external clock on the CKA pin.

The Receiver and Transmitter will subsequently divide the output of the BRG (or the signal from the CKA pin) by 1, 16 or 64, under the control of the DR bit in the CNTLB register, and the X1 bit in the ASCI Extension Control Register. To compute baud rate, use the following formulas.

If ss2,1,0 = 111, baud rate = f

else if BRG mode baud rate = f

/ Clock mode

CKA

/ (2 * (TC+2) * Clock

PHI

mode)

else baud rate = f

/ ((10 + 20*PS) * 2^ss * Clock mode)

PHI

Where: BRG mode is bit 3 of the ASEXT register PS is bit 5 of the CNTLB register

TC is the 16-bit value in the ASCI Time Constant registers The TC value for a given baud rate is:

TC = (f

/ (2 * baud rate * Clock mode)) - 2

PHI

The requirement of having very close to the 50% duty cycle when the CKA pin is used as an input, has been removed on the 189. Minimum High and Low times on CKA0 are typical of most CMOS devices.

RDRF is set, and if enabled an Rx Interrupt or DMA Request is generated, when the receiver transfers a character from the Rx Shift Register to the Rx FIFO. The FIFO merely provides margin against overruns. When there’s more than one character in the FIFO, and software or a DMA channel reads a character, RDRF either remains set or is cleared and then immediately set again. Similarly, if a receive interrupt service routine doesn’t read all the characters in the RxFIFO, RDRF and the interrupt request remain asserted.

The Rx DMA request is disabled when any of the error flags PE or FE or OVRN are set, so that software can identify with which character the problem is associated.

Programmable Reload Timer (PRT)

This logic consists of two separate channels, each containing a 16-bit counter (timer) and count reload register. The time base for the counters is derived from the system clock (divided by 20) before reaching the counter. PRT channel 1 provides an optional output to allow for waveform generation.

Clock mode depends on bit 4 in ASEXT and bit 3 in CNTLB:

X1 DR Clock Mode

00=16 01=64 10=1 1 1 = Reserved, do not use.

2^ss depends on the three LS bits of the CNTLB register:

ss2 ss1 ss0 2^ss

000=1 001=2 010=4 011=8 100=16 101=32 110=64 1 1 1 = External Clock from CKA0

(see above).

The T

output of PRT1 is available on a multiplexed pin.

OUT

Clocked Serial I/O (CSIO)

The CSI0 channel provides a half-duplex serial transmitter and receiver. This channel can be used for simple highspeed data connection to another microprocessor or microcomputer.

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/M1

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

If the M1E bit of the operation Mode Control Register is set to 1, the RETI cycle occurs only once. The /M1 output is asserted LOW during the opcode fetch cycle, the /INT0 acknowledge cycle, and the first machine cycle of the /NMI

acknowledge. When M1E bit is rest to 0, the /M1 output is normally inactive an asserted LOW only during the refetch of the RETI instruction sequence and during /INTO acknowledge cycle.

Z8S180 POWER-DOWN MODES

The following is a detailed description of the enhancements to the Z8S180 from the standard Z80180 in the areas of STANDBY, IDLE, and STANDBY-QUICK RECOVERY modes.

Add-On Features

There are five different power-down modes. SLEEP and SYSTEM STOP are inherited from the Z80180. In SLEEP

Table 14. Power Down Modes

Power-Down CPU On-Chip Recovery Recovery Time Modes Core I/O OSC. CLKOUT Source (Minimum)

mode, the CPU is in a stopped state while the on-chip I/Os are still operating. In I/O STOP mode, the on-chip I/Os are in a stopped state while leaving the CPU running. In SYSTEM STOP mode, both the CPU and the on-chip I/Os are in the stopped state to reduce current consumption. The Z8S180 has added two additional power-down modes, STANDBY and IDLE, to reduce current consumption even further. The differences in these power-down modes are summarized in Table 14.

SLEEP Stop Running Running Running RESET, Interrupts 1.5 Clock I/O STOP Running Stop Running Running By Programming SYSTEM STOP Stop Stop Running Running RESET, Interrupts 1.5 Clock

†

IDLE STANDBY

†

Stop Stop Running Stop RESET, Interrupts, BUSREQ 8 +1.5 Clock Stop Stop Stop Stop RESET, Interrupts, BUSREQ 217 +1.5 Clock (Normal Recovery)

26 +1.5 Clock (Quick Recovery)

Notes:

†

IDLE and STANDBY modes are only offered in the Z8S180. Note that the minimum recovery time can be achieved if INTERRUPT is used as the Recovery Source.

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STANDBY Mode

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Z8S180 has been designed to save power. Two lowpower programmable power-down modes have been added; STANDBY mode and IDLE mode. The STANDBY/IDLE mode is selected by multiplexing D6 and D3 of the CPU Control Register (CCR, I/O Address = 1FH). To enter STANDBY mode:

1. Set D6 and D3 to 1 and 0, respectively.

2. Set the I/O STOP bit (D5 of ICR,

I/O Address = 3FH) to 1.

3. Execute the SLEEP instruction.

When the part is in STANDBY mode, it behaves similar to the SYSTEM STOP mode which currently exists on the Z80180, except that the STANDBY mode stops the clock oscillator, internal clocks and reduces the power consumption to a minimum.

Since the clock oscillator has been stopped, a restart of the oscillator requires a period of time for stabilization. An 18bit counter has been added in the Z8S180 to allow for oscillator stabilization. When the part receives an external IRQ or BUSREQ during STANDBY mode, the oscillator is restarted and the timer counts down 217 counts before acknowledgment is sent to the interrupt source.

The clocking is resumed within the Z8S180 and at the system clock output after /RESET is asserted when the crystal oscillator is restarted, but not yet stabilized.

STANDBY Mode Exit with BUS REQUEST

Optionally, if the BREXT bit (D5 of CPU Control Register) is set to 1, the Z8S180 exits STANDBY mode when the /BUSREQ input is asserted; the crystal oscillator is then restarted. An internal counter automatically provides time for the oscillator to stabilize, before the internal clocking and the system clock output of the Z8S180 are resumed.

The Z8S180 relinquishes the system bus after the clocking is resumed by:

- Tri-State the address outputs A19 through A0.

- Tri-State the bus control outputs /MREQ, /IORQ, /RD and /WR.

- Asserting /BUSACK.

The Z8S180 regains the system bus when /BUSREQ is deactivated. The address outputs and the bus control outputs are then driven High; the STANDBY mode is exited.

The recovery source needs to remain asserted for duration of the 217 count, otherwise standby will be resumed.

The following is a description of how the part exits STANDBY for different interrupts and modes of operation.

STANDBY Mode Exit with /RESET

The /RESET input needs to be asserted for a duration long enough for the crystal oscillator to stabilize and then exit from the STANDBY mode. When /RESET is de-asserted, it goes through the normal reset timing to start instruction execution at address (logical and physical) 0000H.

If the BREXT bit of the CPU Control Register (CCR) is cleared, asserting the /BUSREQ would not cause the Z8S180 to exit STANDBY mode.

If STANDBY mode is exited due to a reset or an external interrupt, the Z8S180 remains relinquished from the system bus as long as /BUSREQ is active.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

STANDBY Mode Exit with External Interrupts

STANDBY mode can be exited by asserting input /NMI. The STANDBY mode may also exit by asserting /INT0, /INT1 or /INT2, depending on the conditions specified in the following paragraphs.

/INT0 wake-up requires assertion throughout duration of clock stabilization time (2

If exit conditions are met, the internal counter provides time for the crystal oscillator to stabilize, before the internal clocking and the system clock output within the Z8S180 are resumed.

1. Exit with Non-Maskable Interrupts

If /NMI is asserted, the CPU begins a normal NMI interrupt acknowledge sequence after clocking resumes.

2. Exit with External Maskable Interrupts

If an External Maskable Interrupt input is asserted, the CPU responds according to the status of the Global Interrupt Enable Flag IEF1 (determined by the ITE1 bit) and the settings of the corresponding interrupt enable bit in the Interrupt/Trap Control Register (ITC: I/O Address = 34H):

a. If an interrupt source is disabled in the ITC, asserting

the corresponding interrupt input would not cause the Z8S180 to exit STANDBY mode. This is true regardless of the state of the Global Interrupt Enable Flag IEF1.

b. If the Global Interrupt Flag IEF1 is set to 1, and if an

interrupt source is enabled in the ITC, asserting the corresponding interrupt input causes the Z8S180 to exit STANDBY mode. The CPU performs an interrupt acknowledge sequence appropriate to the input being asserted when clocking is resumed if:

- The interrupt input follows the normal interrupt daisy chain protocol.

- The interrupt source is active until the acknowledge cycle is completed.

clocks).

If the External Maskable Interrupt input is not active when clocking resumes, the Z8S180 will not exit STANDBY mode. If the Non-Maskable Interrupt (/NMI) is not active when clocking resumes, the Z8S180 still exits the STANDBY mode even if the interrupt sources go away before the timer times out, because /NMI is edge-triggered. The condition is latched internally once /NMI is asserted Low.

IDLE Mode

IDLE mode is another power-down mode offered by the Z8S180. To enter IDLE mode:

1. Set D6 and D3 to 0 and 1, respectively.

2. Set the I/O STOP bit (D5 of ICR,

I/O Address = 3FH) to 1.

3. Execute the SLEEP instruction.

When the part is in IDLE mode, the clock oscillator is kept oscillating, but the clock to the rest of the internal circuit, including the CLKOUT, is stopped completely. IDLE mode is exited in a similar way as STANDBY mode, i.e., RESET, BUS REQUEST or EXTERNAL INTERRUPTS, except that

the 2

bit wake-up timer is bypassed; all control signals are asserted eight clock cycles after the exit conditions are gathered.

STANDBY-QUICK RECOVERY Mode

STANDBY-QUICK RECOVERY mode is an option offered in STANDBY mode to reduce the clock recovery time in STANDBY mode from 217 clock cycles (6.5 ms at 20 MHz) to 26 clock cycles (3.2 µs at 20 MHz). This feature can only

be used when providing an oscillator as clock source.

To enter STANDBY-QUICK RECOVERY mode:

1. Set D6 and D3 to 1 and 1, respectively.

2. Set the I/O STOP bit (D5 of ICR,

I/O Address = 3FH) to 1.

3. Execute the SLEEP instruction.

c. If the Global Interrupt Flag IEF1 is disabled, i.e., reset

to 0, and if an interrupt source is enabled in the ITC, asserting the corresponding interrupt input will still cause the Z8S180 to exit STANDBY mode. The CPU will proceed to fetch and execute instructions that follow the SLEEP instruction when clocking is resumed.

DS971890301

When the part is in STANDBY-QUICK RECOVERY mode, the operation is identical to STANDBY mode except when exit conditions are gathered, i.e., RESET, BUS REQUEST or EXTERNAL INTERRUPTS; the clock and other control signals are recovered sooner than the STANDBY mode.

Note: If STANDBY-QUICK RECOVERY is enabled, the user must make sure stable oscillation is obtained within 64 clock cycles.

Zilog

PRELIMINARY

Z8S180 MPU REGISTER MAP

Notes:

Registers listed in boldface type represent new registers added to the Z8S180. All register addresses not listed are Reserved.

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

ASCI Control Register A Ch 0 %0000/40/80 R/W ASCI Control Register A Ch 1 %0001/41/81 R/W ASCI Control Register B Ch 0 %0002/42/82 R/W ASCI Control Register B Ch 1 %0003/43/83 R/W ASCI Status Register Ch 0 %0004/44/84 R/W ASCI Status Register Ch 1 %0005/45/85 R/W ASCI TX Data Register Ch 0 %0006/46/86 R/W ASCI TX Data Register Ch 1 %0007/47/87 R/W ASCI RX Data Register Ch 0 %0008/48/88 R/W ASCI RX Data Register Ch 1 %0009/49/89 R/W CSIO Control Register %000A/4A/8A R/W CSIO Transmit/Receive Data Reg. %000B/4B/8B R/W Timer Data Register Ch OL %000C/4C/8C R/W Timer Data Register Ch OH %000D/4D/8D R/W Reload Register Ch OL %000E/4E/8E R/W Reload Register Ch OH %000F/4F/8F R/W Timer Control Register %0010/50/90

ASCI0 Extension Control Reg. %0012/52/92 R/W ASCI1 Extension Control Reg. %0013/53/93 R/W

Timer Data Register Ch 1L %0014/54/94 R/W Timer Data Register Ch 1H %0015/55/95 R/W Timer Reload Register Ch 1L %0016/56/96 R/W Timer Reload Register Ch 1H %0017/57/97 R/W Free Running Counter %0018/58/98 R/W

ASCI0 Time Constant Low %001A/5A/9A R/W ASCI0 Time Constant High %001B/5B/9B R/W ASCI1 Time Constant Low %001C/5C/9C R/W ASCI1 Time Constant High %001D/5D/9D RW Clock Multiplier Register %001E/5E/9E RW

CPU Control Register %001F/5F/9F R/W DMA Source Addr Register Ch OL %0020/60/A0 R/W DMA Source Addr Register Ch OH %0021/61/A1 R/W DMA Source Addr Register Ch OB %0022/62/A2 R/W DMA Dest Addr Register Ch OL %0023/63/A3 R/W DMA Dest Addr Register Ch OH %0024/64/A4 R/W DMA Dest Addr Register Ch OB %0025/65/A5 R/W DMA Byte Count Register Ch OL %0026/66/A6 R/W DMA Byte Count Register Ch OH %0027/67/A7 R/W DMA Memory Addr Register Ch 1L %0028/68/A8 R/W DMA Memory Addr Register Ch 1H %0029/69/A9 R/W DMA Memory Addr Register Ch 1B %002A/6A/AA R/W DMA I/O Addr Register Ch 1L %002B/6B/AB R/W DMA I/O Addr Register Ch 1H %002C/6C/AC R/W

DMA I/O Addr Register Ch 1B %002D/6D/AD R/W

DMA Byte Count Register Ch 1L %002E/6E/AE R/W DMA Byte Count Register Ch 1H %002F/6F/AF R/W DMA Status Register %0030/70/B0 R/W DMA Mode Register %0031/71/B1 R/W DMA/WAIT Control Register %0032/72/B2 R/W IL Register %0033/73/B3 R/W INT/TRAP Control Register %0034/74/B4 R/W Refresh Control Register %0036/76/B6 R/W MMU Common Base Register %0038/78/B8 R/W MMU Bank Base Register %0039/79/B9 R/W MMU Common/Bank Area Register %003A/7A/BA R/W Operation Mode Control Register %003E/7E/BE R/W I/O Control Register %003F/7F/BF R/W

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PRELIMINARY

Z8S180 MPU REGISTERS ASCI CHANNELS CONTROL REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon RESET

R/W

CNTLA0

MPE

R/W0R/W0R/W1R/WxR/W0R/W0R/W0R/W

RE TE /RTS0

MPBR/

MOD2 MOD1 MOD0

EFR

0 0 0 Start + 7-Bit Data + 1 Stop 0 0 1 Start + 7-Bit Data + 2 Stop 0 1 0 Start + 7-Bit Data + Parity + 1 Stop 0 1 1 Start + 7-Bit Data + Parity + 2 Stop 1 0 0 Start + 8-Bit Data + 1 Stop 1 0 1 Start + 8-Bit Data + 2 Stop 1 1 0 Start + 8-Bit Data + Parity + 1 Stop 1 1 1 Start + 8-Bit Data + Parity + 2 Stop

Addr 00H

MODE Selection

Read - Multiprocessor Bit Receive Write - Error Flag Reset

Request To Send Transmit Enable Receive Enable Multiprocessor Enable

Bit

Upon RESET

R/W

Figure 32. ASCI Control Register A (Ch. 0)

CNTLA1

MPE RE TE

R/W0R/W0R/W1R/WxR/W0R/W0R/W0R/W

CKA1D

MPBR/

EFR

MOD2 MOD1 MOD0

Addr 01H

MODE Selection

Read - Multiprocessor Bit Receive Write - Error Flag Reset

CKA1 Disable Transmit Enable Receive Enable

DS971890301

Multiprocessor Enable

Figure 33. ASCI Control Register A (Ch. 1)

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PRELIMINARY

Z8S180 MPU REGISTERS (Continued) ASCI CHANNELS CONTROL REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Addr 02H

Clock Source and Speed Select Divide Ratio Parity Even or Odd Clear To Send/Prescale Multiprocessor Multiprocessor Bit Transmit

Bit

Upon Reset

R/W

CNTLB0 MPBT MP

Invalid

R/W0R/W†R/W0R/W0R/W1R/W1R/W1R/W

† /CTS - Depending on the condition of /CTS pin. PS - Cleared to 0.

/CTS/

DRPE0

SS2 SS1 SS0

General PS = 0 PS = 1

Divide Ratio (Divide Ratio = 10) (Divide Ratio = 30)

SS, 2, 1, 0 DR = 0 (x16) DR = 1 (x64) DR = 0 (x16) DR = 1 (x64)

000 Ø ÷ 160 Ø ÷ 640 Ø ÷ 480 Ø ÷ 1920 001 Ø ÷ 320 Ø ÷ 1280 Ø ÷ 960 Ø ÷ 3840 010 Ø ÷ 640 Ø ÷ 2560 Ø ÷ 1920 Ø ÷ 7680 011 Ø ÷ 1280 Ø ÷ 5120 Ø ÷ 3840 Ø ÷ 15360 100 Ø ÷ 2560 Ø ÷ 10240 Ø ÷ 7680 Ø ÷ 30720 101 Ø ÷ 5120 Ø ÷ 20480 Ø ÷ 15360 Ø ÷ 61440 110 Ø ÷ 10240 Ø ÷ 40960 Ø ÷ 30720 Ø ÷ 122880 111 External Clock (Frequency < Ø)

Figure 34. ASCI Control Register B (Ch. 0)

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Addr 03H

Clock Source and Speed Select Divide Ratio

Parity Even or Odd Read - Status of /CTS pin

Write - Select PS Multiprocessor

Multiprocessor Bit Transmit

Bit

Upon Reset

R/W

CNTLB1

MPBT MP Invalid

R/W0R/W†R/W0R/W0R/W1R/W1R/W1R/W

† /CTS - Depending on the condition of /CTS pin. PS - Cleared to 0.

/CTS/

DRPE0

SS2 SS1 SS0

General PS = 0 PS = 1

Divide Ratio (Divide Ratio = 10) (Divide Ratio = 30)

SS, 2, 1, 0 DR = 0 (x16) DR = 1 (x64) DR = 0 (x16) DR = 1 (x64)

Figure 35. ASCI Control Register B (Ch. 1)

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PRELIMINARY

ASCI CHANNELS CONTROL REGISTERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon Reset

R/W

STAT0

RDRF OVRN /DCD0 TDRE TIE

0R0

RIEFE

†

Addr 04H

R0R0R0R/W R††R0R/W

† /DCD0 - Depending on the condition of /DCD0 Pin.

††

TDRE is reset to 0, when /CTSO input is high. /CTS0 Pin = L: TDRE = 1 /CTS0 Pin = H: TDRE = 0

Figure 36. ASCI Status Register

Transmit Interrupt Enable

Transmit Data Register Empty

Data Carrier Detect Receive Interrupt Enable

Framing Error Parity Error

Over Run Error Receive Data Register Full

Bit

Upon Reset

R/W

STAT1

RDRF OVRN CTS1E TDRE TIE

0 R0R

RIEFE

0R0

R/W R/W1R0R/W

Addr 05H

Figure 37. ASCI Status Register (Ch. 1)

Transmit Interrupt Enable

Transmit Data Register Empty

/CTS1 Enable Receive Interrupt Enable Framing Error Parity Error Over Run Error Receive Data Register Full

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

TDR0 Write Only Addr 06H

76543210

Transmit Data

Figure 38. ASCI Transmit Data Register (Ch. 0)

TDR1 Write Only

76543210

Addr 07H

Transmit Data

Figure 39. ASCI Transmit Data Register (Ch. 1)

TSR0 Read Only

xxxxxxxx

Addr 08H

Received Data

765 43210

00000000

New Z8S180 Register

Send Break 0 = Normal Xmit 1 = Drive TXA Low

Break Detect (RO) Break Feature Enable BRG0 Mode

0 = as S180 1 = Enable 16-bit BRG Counter

X1 Bit CLK ASCIO 0 = CKA0 /16 or /64 1 = CKA0 is bit clock

CTS0 Disable 0 = CTS0 Auto-enables Tx 1 = CTS0 Advisory to SW

DCD0 Disable 0 = DCD0 Auto-enables Rx 1 = DCD0 Advisory to SW

Reserved (Program as 0.)

Figure 42. ASCI0 Extension Control Register

(I/O Address 12)

Figure 40. ASCI Receive Data Register (Ch. 0)

TSR1 Read Only Addr 09H

xxxxxxxx

Received Data

Figure 41. ASCI Receive Data Register (Ch. 1)

765 43210

00000000

New Z8S180 Register

Send Break 0 = Normal Xmit 1 = Drive TXA Low

Break Detect (RO) Break Feature Enable BRG1 Mode

0 = As S180 1 = Enable 16-bit BRG Counter

X1 Bit CLK ASCI1 0 = CKA1 /16 or /64 1 = CKA1 is bit Clock

Reserved (Program as 0.)

Figure 43. ASCI1 Extension Control Register

(I/O Address 13)

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PRELIMINARY

ACSI TIME CONSTANT REGISTERS

New Z8S180 Registers

76543210 76543210

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

76543210

CLOCK MULTIPLIER REGISTER (Z180 MPU ADDRESS 1EH)

Bit 7.

X2 Clock Multiplier Mode.

allows the programmer to double the internal clock from that of the external clock. This feature will only operate effectively with frequencies of 10-16 MHz (20-33 MHz internal).

When this bit is set to 1, this

When this bit is set to 0, the Z189 device will operate in normal mode. Upon powerup, this feature is disabled.

Bit 0-6.

Reserved.

New Z8S180 Register

765 43210

Maintains a logic 1 value when read.

01111111

Figure 44. Clock Multiplier Register

(Z180 MPU Address 1EH)

Reserved X2 Clock Multiplier Mode

0 = Disable 1 = Enable

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

CNTR

Bit

EF EIE SS2 SS1 SS0

Upon Reset

R/W

0 R0R/W0R/W0R/W

SS2, 1, 0 Baud Rate

000 Ø ÷ 20 001 Ø ÷ 40 010 Ø ÷ 80 011 Ø ÷ 100

Addr 0AH

-TE

R/W1R/W1R/W

Speed Select

Transmit Enable Receive Enable End Interrupt Enable End Flag

SS2, 1, 0 Baud Rate

100 Ø ÷ 320 101 Ø ÷ 640 110 Ø ÷ 1280 111 External Clock

(Frequency < Ø ÷ 20)

Figure 45. CSI/O Control Register

TRDR Read/Write Addr 0BH

76543210

Read - Received Data Write - Transmit Data

Figure 46. CSI/O Transmit/Receive Data Register

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TIMER DATA REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

TMDR0L Read/Write Addr 0CH

76543210

Figure 47. Timer 0 Data Register L

TMDR1L Read/Write

76543210

Figure 48. Timer 1 Data Register L

Addr 14H

TIMER RELOAD REGISTERS

TMDR0H Read/Write Addr 0DH

15 14 13 12 11 10 9 8

When Read, read Data Register L before reading Data Register H.

Figure 49. Timer 0 Data Register H

TMDR1H Read/Write Addr 15H

15 14 13 12 11 10 9 8

When Read, read Data Register L before reading Data Register H.

Figure 50. Timer 1 Data Register H

RLDR0L Read/Write

76543210

Figure 51. Timer 0 Reload Register L

RLDR1L Read/Write

76543210

Figure 52. Timer 1 Reload Register L

Addr 0EH

Addr 16H

RLDR0H Read/Write

Addr 0FH

15 14 13 12 11 10 9 8

Figure 53. Timer 0 Reload Register H

RLDR1H Read/Write

15 14 13 12 11 10 9 8

Figure 54. Timer 1 Reload Register H

Addr 17H

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TIMER CONTROL REGISTER

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon Reset

R/W

TCR

TIF1 TIF0 TOC0 TDE1 TDE0

TOC1,0 A15/TOUT

00 Inhibited 01 Toggle 10 0 11 1

TIE1

R0R/W0R/W0R/W R/W0R/W0R/W

TOC1TIE0

Addr 10H

Figure 55. Timer Control Register

Timer Down Count Enable 1,0 Timer Output Control 1,0 Timer Interrupt Enable 1,0 Timer Interrupt Flag 1,0

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FREE RUNNING COUNTER

CPU CONTROL REGISTER

PRELIMINARY

FRC Read Only Addr 18H

76543210

Figure 56. Free Running Counter

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Z8S180 has an additional register which allows the programmer to select options that directly affect the CPU performance as well as controlling the STANDBY operating mode of the chip. The CPU Control Register (CCR) allows the programmer to change the divide-by-two internal clock to divide-by-one. In addition, applications where

CPU Control Register (CCR)Addr 1FH

D7 D6 D5 D4 D3 D2 D1 D0

00000000

Clock Divide 0 = XTAL/2 1 = XTAL/1

Standby/Idle Enable 00 = No Standby 01 = IdleAfter Sleep 10 = Standby After Sleep 11 = StandbyAfter Sleep 64 Cycle Exit (Quick Recovery)

BREXT 0 = Ignore BUSREQ In Standby/Idle 1 = Standby/Idle Exit on BUSREQ

EMI noise is a problem, the Z8S180 can reduce the output drivers on selected groups of pins to 33% of normal pad driver capability which minimizes the EMI noise generated by the part.

LNAD/DATA 0 = Standard Drive 1 = 33% Drive On

A19-A0, D7-D0

LNCPUCTL 0 = Standard Drive 1 = 33% Drive On CPU Control Signals

LNIO 0 = Standard Drive 1 = 33% Drive or ASCI Signals

LNPHI 0 = Standard Drive 1 = 33% Drive On EXT.PHI Clock

Figure 57. CPU Control Register

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 7.

programmer to set the internal clock to divide the external clock by 2 if the bit is 0 and divide-by-one if the bit is 1. Upon reset, this bit is set to 0 and the part is in divide-by-two mode. Since the on-board oscillator is not guaranteed to operate above 20 MHz, an external source must be used to achieve the maximum 33 MHz operation of the part, i.e., an external clock at 66 MHz with 50% duty cycle.

If an external oscillator is used in divide-by-one mode, the minimum pulse width requirement must be satisfied.

Bits 6 and 3. used for enabling/disabling the IDLE and STANDBY mode.

Setting D6, D3 to 0 and 1, respectively, enables the IDLE mode. In the IDLE mode, the clock oscillator is kept oscillating but the clock to the rest of the internal circuit, including the CLKOUT, is stopped. The Z8S180 enters IDLE mode after fetching the second opcode of a SLEEP instruction, if the I/O STOP bit is set.

Setting D6, D3 to 1 and 0, respectively, enables the STANDBY mode. In the STANDBY mode, the clock oscillator is stopped completely. The Z8S180 enters STANDBY after fetching the second opcode of a SLEEP instruction, if the I/O STOP bit is set.

Setting D6, D3 to 1 and 1, respectively, enables the STANDBY-QUICK RECOVERY mode. In this mode, its operations are identical to STANDBY except that the clock recovery is reduced to 64 clock cycles after the exit conditions are gathered. Similarly, in STANDBY mode, the Z8S180 enters STANDBY after fetching the second opcode of a SLEEP instruction, if the I/O STOP bit is set.

Clock Divide Select.

STANDBY/IDLE Enable.

Bit 7 of the CCR allows the

These two bits are

Bit 5.

BREXT.

honor a bus request during STANDBY mode. If this bit is set to 1 and the part is in STANDBY mode, a BUSREQ is honored after the clock stabilization timer is timed out.

Bit 4.

LNPHI.

PHI Clock output. If this bit is set to 1, the PHI Clock output is reduced to 33% of its drive capability.

Bit 2.

LNIO.

external I/O pins of the Z80189/Z80L189. When this bit is set to 1, the output drive capability of the following pins is reduced to 33% of the original drive capability:

Bit 1.

LNCPUCTL.

the CPU Control pins. When this bit is set to 1, the output drive capability of the following pins is reduced to 33% of the original drive capability:

Bit 0.

LNAD/DATA.

the Address/Data bus output drivers. If this bit is set to 1, the output drive capability of the Address and Data bus output is reduced to 33% of its original drive capability.

This bit controls the ability of the Z8S180 to

This bit controls the drive capability on the

This bit controls the drive capability of the

- CKS - TxAI

- RxS/CTS1 - CKA0/DREQ0

- TxS - TxA0

- CKAI/TEND0 - /RTS0

This bit controls the drive capability of

- /BUSACK - /MREQ - TEST

- /RD - /IORQ - STATUS

- /WR - /RFSH

- /M1 - /HALT

- E - /TEND1

This bit controls the drive capability of

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DMA REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

SAR0L Read/Write Addr 20H

SA7 SA0

SAR0H Read/Write Addr 21H

SA15 SA8

SAR0B Read/Write Addr 22H

SA16SA19

----

Bits 0-2 (3) are used for SAR0B

A19,

A18,

A17,

A16

x x

DMATransfer Request

ext (CKA0//DREQ0

ASCI0 Rx

ASCI1 Rx

ext (/DREQ1)

Figure 58. DMA 0 Source Address Registers

BCR0L Read/Write

Addr 26H

BC7 BC0

BCR0H Read/Write

Addr 27H

BC15 BC8

Figure 60. DMA 0 Byte Counter Registers

MAR1L Read/Write

MA7 MA0

MAR1H Read/Write

MA15 MA8

Addr 28H

Addr 29H

DAR0L Read/Write Addr 23H DA7 DA0

DAR0H Read/Write Addr 24H

DA15 DA8

DAR0B Read/Write Addr 25H

----

Bits 0-2 (3) are used for DAR0B

A19,

A18,

A17,

x x x

A16

0 1

DA16DA19

DMATransfer Request ext (CKA0//DREQ0)

ASCI0 Tx ASCI1 Tx ext (/DREQ1)

MAR1B Read/Write

----

Addr 2AH

MA16MA19

Figure 61. DMA 1 Memory Address Registers

Figure 59. DMA 0 Destination Address Registers

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

IAR1L Read/Write

IA7 IA0

IAR1H Read/Write

IA15 IA8

Addr 2BH

Addr 2CH

IAR1B Addr 2D

D7 D6 D5 D4 D3 D2 D1 D0

BCR1L Read/Write

BC7 BC0

BCR1H Read/Write

BC15 BC8

Addr 2EH

Addr 2FH

Figure 63. DMA 1 Byte Count RegistersFigure 62. DMA I/O Address Registers

New Z8S180 Register

000 = DMA1 ext TOUT/DREQ 001 = DMA1 ASCI0 010 = DMA1 ASCI1 011 = DMA1 ext CKA0//DREQ0 111 = Reserved, do not program

Reserved, program as 0.

Currently selected DMA Channel when Bit 7 = 1

Alternating Channels 0 = DMA Channels are independent 1 = Toggle between DMA channels for same device

Figure 64. DMA I/O Address Register Ch. 1

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DMA REGISTER DESCRIPTION

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 7. This bit should be set to 1 only when both DMA

channels are set to take their requests from the same device. If this bit is 1 (it resets to 0), the TEND output of DMA channel 0 sets a flip-flop, so that thereafter the device’s request is visible to channel 1, but is not visible to channel

0. The internal TEND signal of channel 1 clears the FF, so that thereafter, the device’s request is visible to channel 0, but not visible to channel 1.

If DMA requests are from differing sources, DMA channel 0 request will be forced onto DMA channel 1 once TEND output of DMA channel 0 sets the flop-flop to alternate.

Bit 6. When both DMA channels are programmed to take their requests from the same device, this bit (FF mentioned in the previous paragraph) controls which channel the device’s request is presented to: 0 = DMA 0, 1 = channel

1. When bit 7 is 1, this bit is automatically toggled by the channel end output of the channels, as described above.

Bits 5-3. Reserved and should be programmed as 0.

Bits 2-0. With “DIM1”, bit 1 of DCNTL, these bits control

which request is presented to DMA channel 1, as follows:

DIM1 IAR18-16 Request Routed to DMA Channel 1

0 000 /DREQ1 0 001 ASCI0 Tx 0 010 ASCI1 Tx 0 011 ext CKA0//DREQ0 0 10X Reserved, do not program. 0 1X0 Reserved, do not program. 0 111 Reserved, do not program

1 000 ext /DREQ1 1 001 ASCI0 Rx 1 010 ASCI1 Rx 1 011 ext CKA0//DREQ0 1 10X Reserved, do not program. 1 1X0 Reserved, do not program. 1 111 Reserved, do not program

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon Reset

D S TAT

DE1 DE0 DIE0

/DWE1

DIE1/DWE0

R/W0R/W1W1W

R/W

Figure 65. DMA Status Register

DMODE

Bit

R/W

- -

110

DM1

R/W0R/W

R/W

SM0 MMOD

SM1DM0

R/W R/W

R/W

Addr 30H

DIME

RR/W

Addr 31H

DMA Master Enable

DMA Interrupt Enable 1, 0

DMA Enable Bit Write Enable 1, 0 DMA Enable Ch 1, 0

Memory MODE Select

DM1, 0

00 01 10

MMOD

0 1

Destination

M M M

I/O

Mode

Cycle Steal Mode Burst Mode

Address

DAR0+1

DAR0-1 DAR0 Fixed DAR0 Fixed

SM1, 0

00 01 10

Figure 66. DMA Mode Registers

Source

M M M

I/O

Ch 0 Source Mode 1, 0

Ch 0 Destination Mode 1, 0

Address SAR0+1

SAR0-1 SAR0 Fixed SAR0 Fixed

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DMA REGISTERS (Continued)

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon Reset

R/W

DCNTL

MWI1 MWI0 DMS0 DIM1 DIM0

111

MWI1, 0

00 01 10 11

DMSi

1 0

IWI1

R/W1R/W

No. of Wait States

0 1 2 3

Sense

Edge Sense Level Sense

DMS1IWI0

R/W R/WR/WR/W R/W

R/W

IWI1, 0

00 01 10 11

No. of Wait States

Addr 32H

DMA Ch 1 I/O Memory

Mode Select

/DREQi Select, i = 1, 0

I/0 Wait Insertion

Memory Wait Insertion

1 2 3 4

DM1, 0

00 01 10

Note:

* If using ROM/RAM Chip Select wait state generators, the Z180 wait state generator should be set to 0.

Transfer Mode

M - I/O M - I/O I/O - M I/O - M

Address Increment/Decrement

MAR1+1

MAR1-1 IAR1 Fixed IAR1 Fixed

Figure 67. DMA/WAIT Control Register

IAR1 Fixed IAR1 Fixed

MAR1+1

MAR1-1

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SYSTEM CONTROL REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Upon Reset

Bit

Upon Reset

R/W

Bit

R/W

IL7 IL6 - - -

000

R/WR/W

Figure 68. Interrupt Vector Low Register

ITC

TRAP UFO ITE2 ITE1 ITE0

001

R/W

00000

110

--IL5

---

R/W

Addr 33H

Interrupt Vector Low

Addr 34H

R/WRR/W R/W

/INT Enable 2, 1, 0

Undefined Fetch Object TRAP

Bit

Upon Reset

R/W

Figure 69. INT/TRAP Control Register

RCR

REFE REFW

111

CYC1, 0

00 01 10 11

Interval of Refresh Cycle

11100

10 states 20 states 40 states 80 states

CYC1 CYC0

R/WR/WR/W R/W

Addr 36H

Cycle Select

Refresh Wait State Refresh Enable

DS971890301

Figure 70. Refresh Control Register

Zilog

MMU REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit

Upon Reset

R/W

Bit

Upon Reset

R/W

CBR

CB7 CB6 CB2 CB1 CB0

000

R/W0R/W

CB3CB4CB5

R/W R/WR/WR/W R/W

R/W

Addr 38H

Figure 71. MMU Common Base Register

BBR

BB7

BB6 BB2 BB1 BB0

000

R/W0R/W

BB3BB4BB5

R/W R/WR/WR/W R/W

R/W

Addr 39H

Figure 72. MMU Bank Base Register

MMU Common Base Register

MMU Bank Base Register

Bit

Upon Reset

R/W

CBAR

CA3 CA2 BA2 BA1 BA0

111

R/W1R/W

BA3CA0CA1

R/W R/WR/WR/W R/W

R/W

Addr 3AH

Figure 73. MMU Common/Bank Area Register

MMU Bank Area Register MMU Common Area Register

DS971890301

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SYSTEM CONTROL REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Upon Reset

R/W

Bit

Upon Reset

R/W

OMCR

M1E /M1TE

Bit

111

Notes:

1. This register should be programmed to 0x0xxxxxb (x = don't care) as a part of Initialization.

2. If the M1E bit is set to 1, the processor does not fetch a RETI instruction.

ICR

IOA7 IOA6

000

Addr 3EH

/IOC

---

11111

WR/W R/W

Figure 74. Operation Mode Control Register

Addr 3FH

IOSTP

11111

R/WR/W R/W

---

I/O Compatibility /M1 Temporary Enable /M1 Enable

Figure 75. I/O Control Register

I/O Stop I/O Address

Combination of 11 is reserved

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189 MIMIC REGISTER MAP

MMC MIMIC Master Control Reg. XXFF R/W None IUS/IP Interrupt Pending XXFE R/Wb7 None IE Interrupt Enable XXFD R/W None IVEC Interrupt Vector XXFC R/W None RTCR Receive Time Constant XXFB R/W None

TTCR Transmit Time Constant XXFA R/W None DLM Divisor Latch (MSByte) XXF9 R only 01,DLAB=1,R/W DLL Divisor Latch (LSByte) XXF8R only 00,DLAB=1,R/W SCR Scratch Register XXF7 R only 07 R/W MSR Modem Status Register XXF6 R/Wb7-4 06 R only

LSR Line Status Register XXF5 R/Wb6432 05 R only MCR Modem Control Register XXF4 R only 04 R/W LCR Line Control Register XXF3 R only 03 R/W IER Interrupt Enable Register XXF1 R only 01,DLAB=0 R/W

RBR Receiver Buffer Register XXF0 W only 00,DLAB=0 R only THR Transmitter Holding Reg. XXF0 R only 00,DLAB=0 W only FSCR FIFO Status and Control XXEC R/W7-4 None TTTC Tran. Timeout Time Const. XXEB R/W None RTTC Rec. Timeout Time Const. XXEA R/W None IIR Interrupt Identification None 02 R only FCR FIFO Control Register XXE9 R only 02 W only

Z80189/Z8L189

Z80189 PC DMA MAILBOX BRG,COM_PORT, PIA AND MISC REGISTERS

PA Data Direction Register XXEDH R/W None PA Data Register XXEEH R/W None MIMIC Modification Register XXE9 W only None ROM Address Boundary Reg. XXE8 R/W None RAMLBR RAM Lower Boundary Reg. XXE7 R/W None RAMUBR RAM Upper Boundary Reg. XXE6 R/W None PB Data Register XXE5 R/W None

PB Data Direction Register XXE4 R/W None BRG High Constant XXE1 R/W None BRG Low Constant XXE0 R/W None Interrupt Edge/Pin Mux Control XXDF R/W None PC Data Register XXDE R/W None

PC Data Direction Register XXDD R/W None Z80189 Enhancements Register XXD9 R/W None WSG Chip Select Register XXD8 R/W None IOBRG Register XXD6 R/W None COM Decode Register XXD7 R/W None System Configuration Register XXEF R/W None

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Z80189 MAILBOX REGISTER MAP

Host I/O Status Register %XXD5 W bit 1/R Prog + 10b R (2) Host Output Register 1 %XXD4 R Prog + 01b W (2) Host Input Register 1 %XXD4 W Prog + 01b R (2) Host Output Register 0 %XXD3 R Prog + 00b W (2) Host DMA Mailbox Cntrl Reg %XXD2 R/W None Host DMA Transmit Register 1 %XXD1 R DMA1 W (3) Host DMA Receive Register 1 %XXD1 W DMA1 R Host DMA Transmit Register 0 %XXD0 R (1) DMA0 W Host DMA Receive Register 0 %XXD0 W DMA0 R

1. This register is defaulted to 91h to indicate revision code. (Z189 revision #1 - Z80189AA)

2. The PC Host Addresses are HA9:2 are programmable by writing to PADATA.

3. The HDMAT1 can be used as an extra host output mailbox register. If the Host DMA Mailbox 1 function is disabled

(bit 1 of HMC register is zero), a Host write in the programmed Mailbox range with HA1, 0=1,1 will cause the host data to be latched into the HDMAT1 register.

Note: All register addresses not listed are Reserved.

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16550 MIMIC INTERFACE

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Z80189 has a 16550 MIMIC interface that allows it to mimic the 16550 device. It has all the interface pins necessary to connect up to the PC/XT/AT bus without any extra circuitry. It contains the complete register set of the 16550 part with the same interrupt structure. The data path allows parallel transfer of data to and from the register set by the internal Z80180 of the Z80189. There is no shift register associated with the MIMIC of the 16550 UART. This interface saves the application from doing a serial transfer before performing data compression or error correction on the data.

Control of the register set is maintained by six priority encoded interrupts to the Z80189. When the PC/XT/AT writes to THR, MCR, LCR, DLL, DLM, FCR or reads the RBR, an interrupt to the Z80189 is generated. Each interrupt can be individually masked off or all interrupts can be disabled by writing a single bit. Both mode 0, mode 1 and mode 2 interrupts are supported by the 16550 MIMIC interface.

Two 8-bit timers are also available to control the data transfer rate of the 16550 MIMIC interface. Their input is tied to the BRG clock so a down count of 24 bits is possible.

An additional two 8-bit timers are available for programming the FIFO time-out feature (4 Character Time Emulation) for both Receiver and Transmitter FIFO’s.

The 16550 MIMIC interface supports the PC/XT/AT interrupt structure as well as an additional mode that allows for a wired AND interrupt structure.

All registers of the 16550 MIMIC interface are accessible in any page of I/O space since only the lowest 8 address lines are decoded.

COM Port Decode functionality is integrated into the Z189. This allows the MIMIC to be selected for a specific COM Port Address (PC COM Port Address 1-4). Previously for the Z80182, the COM Port Address selected for the MIMIC was implemented through external COM Port Decode circuitry. The COM Port Decode circuitry in the Z80189 simplifies this process by allowing the user to select the MIMIC Com Port addresses through software, as well as reducing the system board level costs by saving board space and external circuitry.

See Figure 76 for a block diagram of the 16550 MIMIC interface.

PC Side

Host Addr Decode

Host Data Bus

PC IRQ

PC DMA Control

Selectable

COM Port Decode

16550 MIMIC

PC Host IRQ

PC DMA Mailbox

and I/O Mailbox

Rx Timer

Tx Timer

D A T A

B U S

Z80180 Control

Figure 76. 16550 MIMIC Block Description

IRQ &

Control

Config

Z80180 Data Bu

180 Side

Z80180 Address

DS971890301

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16550 MIMIC FIFO DESCRIPTION

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The receiver FIFO consists of a 16-word FIFO capable of storing eight data bits and three error bits for each character stored (Figure 77). Parity error, Framing error and Break detect bits are stored, along with the data bits, by copying their value from three shadow bits, which are write only bits for the Z80180 MPU LSR address. The three shadow bits are cleared after they are copied to the FIFO memory. In FIFO mode, to write error bits into the receiver FIFO, the MPU must first write the Parity, Framing and Break detect status to the Line Status Register (shadow bits) and then write the character associated into the receiver buffer. The data and error bits will then move into the same address in the FIFO. The error bits become available to the PC side of the interface when that particular location becomes the next address to read (top of FIFO). At that time they may either be read by the PC by accessing them in the LSR, or they may cause an interrupt to the PC interface if so enabled. The error bits are set by the error status of the byte at the top of the FIFO but may only be cleared by reading the LSR. If successive reads of the receiver FIFO are performed without reading the LSR, the status bits will be set if any of the bytes read have the respective error bit set.

The PC interface may be interrupted when 1, 4, 8 or 14 bytes are available in the receiver FIFO by setting bits 6 and 7 in the FCR (FIFO Control Register, PC address 02h to the appropriate value. If the FIFO is not empty, but below the above trigger value, a time-out interrupt is available if the receiver FIFO is not written by the MPU or read by the PC by an interval determined by the Character Time-out Timer. This is an additional Timer with MPU access only which is used to emulate the 16550 4 character time-out delay. The timer receives the BRG as its input clock.

Software must determine the correct values to program into the Receiver Time-out register and the BRG to achieve the correct delay interval for time-out. These interrupts are cleared by the FIFO reaching the trigger point or by resetting the Time-out interval timer by FIFO MPU write or PC read access.

With FIFO mode enabled, the MPU is interrupted when the receiver FIFO is empty, corresponding to bit 5 being set in the IUS/IP register (MPU access only). This bit corresponds to a PC read of the receiver buffer in non-FIFO (16450) mode. The interrupt source is cleared when the FIFO becomes non-empty or the MPU reads the IUS/IP register.

The transmitter FIFO is a 16 byte FIFO with PC write and MPU read access (Figure 78). In FIFO mode, the PC will receive an interrupt when the transmitter becomes empty corresponding to bit 5 being set in the LSR. This bit and the interrupt source are cleared when the transmitter FIFO becomes non-empty or the IIR register is read by the PC.

On the MPU interface, the transmitted data available can be programmed to interrupt the MPU on 1, 4, 8 or 14 bytes of available data by seeing the appropriate value in the MPU FSCR control register (MPU write only XXECH) bits 6 and 7. A time-out feature exists, Transmitter Time-out Timer, which is an additional 8 bit timer with BRG as the input source. If the transmitter FIFO is non-empty and no PC write or MPU read of the FIFO has taken place within the timer interval, a time-out will occur causing a corresponding interrupt to the MPU.

DS971890301

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PRELIMINARY

16550 MIMIC FIFO DESCRIPTION (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

MPU Write LSR Shadow B2-B4

MPU_RD

MPU Databus (MPU Side Write)

phi

MPU

IRQ

phi

Sync

16x3 Error

Bits

Read

Pointer

error

R E A D

B U

F E R

I T E

F F E

Write

Pointer

16x8

Data Bits

ALU

phi

Sync

PC Read LSR B2-B4

PC_RD

PC Side Databus

(PC Side Read)

FIFO Control

IRQ

MPU Side Interface

16550

MIMIC or

PC Side Interface

Figure 77. Receiver FIFO Block Diagram

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

PC_WR

Write

IRQ

phi

Sync

phi

I T E

B U

F E R

Write

Pointer

16x8

Data Bits

ALU

Read

Pointer

R E A D

B U F F E R

Sync

MPU_RD

MPU Rea (Data)

FCR Reg

MPU IRQ

16550 MIMIC or PC side interface

16550 MIMIC o PC Side Interfac

Figure 78. Transmitter FIFO Block Diagram

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

16550 MIMIC FIFO DESCRIPTION (Continued)

Table 15. 16550 Line Status Register

Error Description How to Set How to Clear

Error in At least one data byte available At least one error in receiver When there are no more RCVR in FIFO with one error FIFO errors FIFO

*TEMT Transmitter empty MPU writes a 1 MPU writes a 0

† *THRE Transmitter holding When MPU has When holding register

the holding register

Break Break occurs when MPU writes 1 There is a Detect received data input PC-side read

is held in logic-0 of the LSR for longer than a full word transmission

Framing Received character MPU writes 1 There is a Error did not have a valid PC-side read

stop bit of the LSR

Z80189/Z8L189

Parity Received character MPU writes 1 There is a Error did not have correct PC-side read

even or odd parity of the LSR

Overrun Overlapping received MPU makes There is a Error characters, thereby two writes PC-side read

destroying the to receiver of the LSR previous character buffer register

†Data Indicates complete MPU writes to Empty Receiver Ready incoming data has RCVR FIFO or or Receiver FIFO

been received receiver buffer

Notes:

* The TEMT and THRE bits take on different functions when

TEMT/Double Buffer mode is enabled.

† These signals are delayed to HOST when using character

emulation delay.

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PRELIMINARY

Z80189 MIMIC SYNCHRONIZATION CONSIDERATIONS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Because of the asynchronous nature of the FIFO’s on the MIMIC, some scheme of synchronization must be provided to prevent conflict from the dual port accesses of the MPU and the PC.

To solve this problem, I/O to the FIFO is buffered, the buffers allowing both PC and MPU to access the FIFO asynchronously. Read and Write requests are then synchronized by means of the MPU clock. Incoming signals are buffered in such a way that meta-stable input levels will be stabilized to valid 1 or 0 levels. Actual transfers to and from the buffers from and to the FIFO memory are timed by the MPU clock. ALU evaluation is performed on a different phase than the transfer to ensure stable pointer values.

Another potential problem is that of simultaneous access of the MPU and PC to any of the various ‘mailbox’ type registers. This is solved by dual buffering of the various read/write registers. During a read access by either MPU or PC to a mailbox register, the data in the buffered slave register is not permitted to change. Any write that might take place during this time will be stored in the input of the master register. The corresponding status/interrupt will be reset as appropriate based on the write having followed the read to the register. For example, the IUS/IP bit for the LCR write will not be cleared by the MPU read of the LCR if a simultaneous write to the LCR by the PC takes place. Instead the LSR data will change after the read access and IUS/IP bit 3 will remain at logic 1.

DOUBLE BUFFERING FOR THE TRANSMITTER IN 16450 MODE

The Z80189 implements double buffering for the transmitter in 16450 mode and sets the TEMT bit in the LSR Register automatically.

If character delay emulation is being used (see Figure 79):

1. The PC THRE bit in the LSR Register is set when the THR Register is empty;

2. PC Host writes to the 16450 THR Register;

3. Whenever the Z80189 TSR buffer is empty and one character delay timer is in a time out state, the byte from the THR Register is transferred to the TSR buffer;

4. Restart character delay timer (timer reloads and counts down) with byte transfer from THR Register to the TSR buffer;

7. TEMT bit in LSR Register for MPU is set with no delay whenever the TSR buffer is empty;

8. When the TSR buffer is read by MPU and THR Register is empty and one character delay timer reaches zero the TEMT bit in the LSR Register for Host is set from 0 to 1.

The PC THRE bit in the LSR Register is reset whenever the THR Register is full and set whenever THR Register is empty. MPU IREQ and DMA Request for the transmit data is triggered whenever the TSR buffer is full and cleared whenever TSR buffer is empty.

If character delay emulation is not used the TEMT bit in the LSR Register is set whenever both the THR Register and the TSR buffer are both empty. The Host TEMT bit is clear if there is data in either the TSR buffer or THR Register.

5. Whenever the TSR buffer is full, the TEMT bit in LSR Register for MPU is reset with no delay;

6. MPU reads TSR buffer;

DS971890301

Disable this feature when 16550 FIFO mode is enabled.

Zilog

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

DOUBLE BUFFERING FOR THE TRANSMITTER IN 16450 MODE (Continued)

Host Write

Z80189/Z8L189

Empty/Full

Host & MPU THRE =

(MPU TEMT) TSRE =

Host TEMT = 1 if -THRE = 1 and

-TSRE = 1 and

- Emulation delay timer is timed out

Note: MPU seesTSR bit in the LSR Register as TEMT bit

1 0

Empty/Full

1 0

16450

THR

THR to TSR

delay

transfer

TSR

Transmit Shift Reg. Emulation

Byte Transfer if:

- THRE=0; and

- TSRE = 1; and

- Character delay timer is timed out. Note: Timer reloads and counts down

whenever data is transferred fromTHR to TSR.

Added TSR Buffer for the transmit data

Figure 79. TEMT Emulation Logic Implementation

Z80189 MIMIC DMA Consideration

Since the /HRXRDY and /HTXRDY is removed in the Z189, the MIMIC DMA feature found on the Z182 is not available on the Z189.

Z80189 MIMIC Design Hint

The MIMIC output drive capability has been increased to 16 mA on the Z189. This may eliminate the need for buffering to the PC Bus.

DS971890301

Zilog

PRELIMINARY

16550 MIMIC INTERFACE REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The 16550 MIMIC interface is controlled by the MMC register. Setting it allows for different modes of operation such as using the eight bit counters and which IRQ structure is used with the PC/XT/AT.

765 43210

00000000

VIS Vector Include Status 0 = Mode 0 Interrupts 1 = Mode 2 Interrupts

HINTR1 00 = Normal 01 = Wire And 10 = Out 2 Control 11 = Reserved

Reserved as 0 Reserved as 0

Reserved as 0 Rx Timer Enable Tx Timer Enable

Figure 80. MIMIC Master Control Register

(Z180 MPU Address XXFFH)

Bit 7 Transmit Timer Delay Counter Enable (Read/Write)

If bit 7 is set to a one, it enables the transmit delay timer. When the Z180 reads the Transmit Register, the transmit delay timer is automatically loaded with the Transmit Time Constant Register and the timer is enabled to countdown to zero. This timer delays setting the Transmitter Holding Register Empty (THRE) bit until the timer times out. If this bit is zero, then THRE is set immediately on a Z180 read of the Transmit Register.

Both counters are single pass and stop on a count of zero. Their purpose is to delay data transfer just as if the 16550 UART had to shift the data in and out. This is provided to alleviate any software problems a high speed continuous data transfer might cause to existing software. If this is not a problem, then data can be read and written as fast as the two machines can access the devices. In FIFO mode of operation, the timers are used to delay the status to the PC interface by the time that would be required to actually shift the characters out or in if an actual UART were present.

Bit 5 Reserved as 0 Bit 4 Reserved as 0

Bit 3 Reserved as 0

Bit 2,1 Interrupt Select (Read/Write)

Bits 2, 1

00 If both bits 2 and 1 are set to zero, then the active

HINTR1 pin is set to normal 16550 MIMIC mode.

01 If bit 2 is zero and bit 1 is one, then the 16550

MIMIC will enable a wire AND condition on the active HINTR1 pin to the PC/XT/AT.

10 If bit 2 is one and bit 1 is zero, then the active

HINTR1 pin will be driven only if out 2 of the Modem Control register is a one. If out 2 is a zero, then the active HINTR1 pin will be tri-stated.

11 Both bits should never be set to one. This is a

reserved condition and should not be used.

Bit 0 Vector Include Status (Read/Write)

This bit is used to select the interrupt response mode of the Z180. A 0 in this bit enables mode 0 interrupts; a 1 enables mode 2 response.

Bit 6 Receive Timer Delay Counter Enable (Read/Write)

If bit 6 is set to a one, it enables the receive delay timer. When the Z180 writes to the Receive Buffer, it loads the receive delay timer from the Receive Time Constant Register and enables the timer to countdown to zero. This timer delays setting the Data Ready (DR) bit in the LSR until the timer times out. If this bit is a zero, then DR is set immediately on a Z180 write to the Receive Buffer.

DS971890301

Zilog

PRELIMINARY

16550 MIMIC INTERRUPT REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

IUS/IP Register

The IUS/IP Register is used by the Z180 MPU to determine what has caused the Interrupt. This register will have the appropriate bit set when an interrupt occurs.

765 43210

00010000

Interrupt Pending 6 THR Write 5 TTO Transmitter Timeout 4 RBR Read 3 MCR Write 2 LCR Write 1 DLL Write 1 DLM Write 0 FCR Write or Tx Overrun

Interrupt Under Service (RD) Reset Highest IUS (WR)

Figure 81. IUS/IP Register

(Z180 MPU Address XXFEH)

Bit 7 Interrupt Under Service (Read/Write)

This bit represents a logical OR of each individual IUS bit for the internal MIMIC interrupt daisy chain. An IUS bit is set when an interrupt is registered (IP set) and enabled (IE set), the incoming IEI daisy chain is active (chain enabled) and an interrupt acknowledge cycle is entered. By writing a ‘1’ to this bit the highest priority IUS bit that is set will be reset. Writing a ‘0' to this bit has no effect.

Bit 6 Transmitter Holding Register Written (Read Only)

This bit is set when the PC/XT/AT writes to the Transmitter Holding Register. It is reset when the Z180 MPU reads the Transmitter Holding Register. In FIFO mode, this bit is set when the trigger level is reached (4, 8, 14 bytes available).

Bit 5 Transmitter Time-out with Data in FIFO (Read Only)

This bit is set when the transmitter FIFO has been idle (no read or write and timer decrements to zero) with data bytes below the trigger level. It is cleared when the FIFO is read or written.

Bit 4 Receive Buffer Read (Read Only)

This bit is set when the PC/XT/AT reads the Receive Buffer Register. It is reset when the Z180 MPU writes to the Receive Buffer Register. In FIFO mode, this bit is set upon the PC reading all the data in the receiver FIFO. Note: RBR is set and interrupts when the receiver FIFO has been emptied by the PC. This bit and interrupt are cleared when one or more bytes are written into the receiver FIFO by the MPU.

Bit 3 Modem Control Register Write (Read Only)

This bit is set when the PC/XT/AT writes to the Modem Control Register. It is reset when the Z180 MPU reads the Modem Control Register.

Bit 2 Line Control Register Write (Read Only)

This bit is set when the PC/XT/AT writes to the Line Control Register. It is reset when the Z180 MPU reads the Line Control Register.

Bit 1 Divisor Latch LS/MS Write (Read Only)

This bit is set when the PC/XT/AT writes to the Divisor Latch Least Significant or Most Significant bytes. It is reset when the PC reads the LS/MS register(s). To determine which byte(s) have been written, the Z180 must read either LS or MS locations and then repoll this bit. If only one location is interrupting, the interrupt will be cleared when that location is read by the Z180.

Bit 0 FIFO Control Register Write (Read Only)

This bit is set when the PC/XT/AT writes to the FCR. It is reset when the Z180 MPU reads this register.

If THR timer is enabled, this interrupt is delayed by the number of character times programmed as the trigger level.

Note: The THR bit is set (interrupts) when the transmitter FIFO reaches the data available trigger level set in the MPU FSCR control register. The bit and interrupt source is cleared when the number of data bytes falls below the set trigger level.

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Interrupt Enable Register

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The IE Register allows each of the 16550/8250 interrupts to the Z180 MPU to be masked off individually or globally.

765 43210 00000000

Interrupt Enable 6 Enable THR IRQ 5 Enable TTO IRQ 4 Enable RBR IRQ 3 Enable MCR IRQ 2 Enable LCR IRQ 1 Enable DLL/DLM IRQ 0 Enable FCR IRQ

MIE

Figure 82. IE Register

(Z180 MPU Address XXFDH)

Bit 7 Master Interrupt Enable (Read/Write)

If bit 7 is a zero, all interrupts from the 16550 MIMIC are masked off. If this bit is a one, then Interrupts are enabled individually by setting the appropriate bit.

Priority of interrupts are in this order:

Highest 6. THR IRQ

5. TTO IRQ

4. RBR IRQ

3. MCR IRQ

2. LCR IRQ

1. DLL IRQ

1. DLM IRQ

Lowest 0. FCR IRQ

Interrupt Vector Register

The Interrupt Vector Register contains either the opcode or the Lower Address for a Z180 interrupt, depending upon the VIS bit in the MMC Register. If the VIS bit is a zero, then Z180 Mode 0 interrupt is selected, if the VIS bit is a one then Z180 Mode 2 is selected.

765 43210

00000000

0/Opcode

Bit 6 Enable THR Interrupt (Read/Write)

If this bit is a one, it enables the Transmitter Holding Register Interrupt.

Bit 5 Enable TTO Interrupt (Read/Write)

If this bit is a one, it enables the Transmitter Time-out Interrupt. This will interrupt the CPU when characters remain in the FIFO below the trigger level and the FIFO is not read or written for the length of time in the transmitter time-out register.

Bit 4 Enable RBR Interrupt (Read/Write)

If this bit is a one, it enables the Receiver Buffer Register Interrupt.

Bit 3 Enable MCR Interrupt (Read/Write)

If this bit is 1, it enables the Modem Control Register Interrupt

Bit 2 Enable LCR Interrupt (Read/Write)

If this bit is a one, it enables the Line Control Register interrupt.

Bit 1 Enable DLL/DLM Interrupt (Read/Write)

If this bit is 1, it enables the Divisor Latch least and Most Significant Byte Interrupts

Bit 0 Enable FCR Interrupt (Read/Write)

If this bit is a one, then interrupts are enabled for a PC write to the FIFO control register (FCR).

Status/Opcode Upper Nibble IVEC

Figure 83. IVEC Register

(Z180 MPU Address XXFCH)

Bit 7-4 Upper Nibble IVEC (Read/Write)

These four bits are to generate either an opcode or the upper four bits of the eight bit address to support the Z180 interrupt modes. These bits are read/write and always read back what was last written to them.

Bits 3-1 Status/Opcode (Read/Write)

These three bits are the Interrupt Status bits when VIS in the MMC register is a one. If the VIS bit is a zero, then these bits contain what was last written to them.

Bits 321

000 NO IRQ 001 FCR IRQ 010 DLL/DLM IRQ 011 LCR IRQ 100 MCR IRQ 101 RBR IRQ 110 TTO IRQ 111 THR IRQ

DS971890301

Zilog

PRELIMINARY

Interrupt Vector Register (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 0 Opcode (Read/Write)

This bit is always a zero when the VIS bit is a one. If the VIS bit is a zero, then this bit reads back what was last written to it.

This register serves both interrupt modes. When the VIS bit is a zero, the last value written to the register can be read back. If the VIS bit is a one and an interrupt is pending, the value read will be the last value written to the upper nibble plus the status for the interrupt that is pending. If no interrupt is pending, then the last value written to the upper nibble plus the lower nibble will be read from the register.

If the vector includes the status, then the lower four bits of the vector will change asynchronously depending on the interrupting source. Since this vector changes asynchronously, then the interrupt service routine to read the IVEC register might read the source of the most recent IRQ/ INTACK cycle if that IRQ does not have its IUS set.

765 43210 00000000

FORCE_450 Receive Timeout to PC Host Enable TEMT_DBLBUFF Reserved (Always 0) XMITTimeout Enable

RCVR Timeout Enable XMITTrigger (LSB) XMITTrigger (MSB)

Bit 5 Receiver Time-out Enable

This bit enables the Z80189 Receiver Time-out Timer that is used to emulate the four character time-out delay that is specified by the 16550. An RTO interrupt will occur under the following conditions: no read or write to the RCVR FIFO, data bytes are available, but below the PC trigger level, or the receiver timeout timer reaches zero.

Bit 4 Transmitter Time-out Enable

This bit enables the Z80189 timer that is used to interrupt the Z180 MPU if characters are available, but are below the trigger level. The timer is enabled to count down if this bit is one and the number of bytes is below the set transmitter trigger level. The timer will time-out and interrupt the MPU if no read or write to the XMIT FIFO takes place within the timer interval.

Bit 3 Reserved for Future Use

Always write and read as ‘0’ by users. Writing ‘1’ enables a test mode for emulation timers.

Bit 2 Double Buffer Mode (Write/Read)

(Reset value=0) Setting this bit will enable (only in 16450 mode) the TEMT hardware emulation and transmitter double buffering.

Double Buffer

This enables a transmit shift register (TSR) to act as a slave register, while the PC writes to a transmit holding register. The Z180 reads from the transmit shift register. This allows the PC to write two consecutive bytes into the MIMIC.

Figure 84. FIFO Status and Control Register

(Z180 MPU Read/Write Add XXECH)

Bit 7 and Bit 6 XMIT Trigger MSB, LSB

This field determines the number of bytes available to read in the transmitter FIFO before an interrupt will occur to the MPU:

b7 b6 Level (#bytes)

001 014 108 1114

TEMT Emulation

If character delay emulation is being used, the TEMT is set as follows: The TSR is emptied and the associated delay logic has set the (delayed) THRE bit in the LSR.

At this time a one character delay timer begins. After this timer reaches zero count, the TEMT bit will be set if the THR and TSR output buffer are empty. TEMT is clear whenever there is data in either THR or the TSR output buffer.

Bit 1 Receive Timeout to the PC Host (Write/Read)

(Reset Value=0) setting this bit will enable the RTO timeout to emulate the 16550 device. If enabled, the RTO timer will not start timeout until all delayed characters have been clocked through the receiver character delay emulation logic. This will prevent an RTO from occurring before a (delayed) receiver trigger level interrupt. When cleared, the RTO will begin timeout from the last read or write to the receiver FIFO.

DS971890301

Zilog

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 0 Force 16450 mode (Write/Read)

(Reset value=0) This bit=1 will force the MIMIC into 16450 mode. Bit 0 in the FCR reg is forced to zero as well as the MIMIC internal FIFO enable. Bits 7 and 6 in the IIR will remain at their last value when this bit is set.

765 43210

1111111

Rec Timeout Constant

Figure 85. Receiver Time-out Timer Constant

(Z180 MPU Add XXEAH)

This register contains an 8-bit constant for emulation of the 16550 4 character time-out feature. Software must determine the value to load into this register based on the bit rate and word length specified by the MIMIC interface with the PC. This timer receives its input from the BRG Clock. This timer is enabled to down count when the enable bit in the FSCR register is set and the trigger level has not been reached on the RCVR FIFO. The counter will reload each time there is a read or write to the RCVR FIFO.

765 43210

11111111

Transmitter Timeout Constant

Figure 86. Transmitter Time-out Timer Constant

(Z180 MPU Add XXEBH)

This register contains an 8-bit constant for determining the interval for the transmitter time-out timer. If allowed to decrement to zero, this timer will interrupt the MPU by setting the THR bit in the IUS/IP register. This timer receives its input from the BRG Clock. The timer is enabled to down count when the enable bit in the FSCR register is set and the trigger level has not been reached on the XMIT FIFO. The counter will reload each time there is a read or write to the XMIT FIFO.

TRANSMIT AND RECEIVE TIMERS

Because of the speed at which data transfers can take place between the Z180 MPU and the PC/XT/AT, two timers have been added to alleviate any software problems that a high-speed data transfer might cause. These timers allow the programmer to slow down the data transfer just as if the 16550 MIMIC interface had to shift the data in and out. The Timers receive their input from the BRG Clock. This allows the programmer access to a 24-bit timer to slow down the data transfer.

765 43210 11111111

Transmitter Time Constant

Figure 87. Transmitter Time Constant Register

(Z180 MPU Address XXFAH)

When a write from the PC/XT/AT is made to the Transmitter Holding register, an interrupt to the Z180 MPU is generated. The Z180 MPU then reads the data in the Transmitter

Holding Register. Upon this read if the Transmitter timer is enabled, the time constant from the Transmitter Time Constant Register is loaded into the Transmitter timer and enables the count. After the timer reaches a count of zero, the Transmitter Holding Register Empty bit is set. However, the above is only true when the PC/XT/AT is reading the Transmitter Holding Register Empty bit. To allow the Z180 MPU to know that it has already read the byte of data, a mirrored Transmitter Holding Register Empty bit is set immediately following a read from the Transmitter Holding Register. This mirrored bit is always read back to the Z180 MPU when it reads the Line Status Register. If the transmitter timer is not enabled when the Z180 MPU reads the transmitter holding register, then both Transmitter Holding Register Empty bits are set immediately. In FIFO mode of operation, the effect is similar in that the status to PC is always delayed such that a PC interrupt for empty FIFO will not occur before the time required for each character read from the FIFO by the Z180 has elapsed. The effect is that the PC will not see data requests from an empty FIFO any faster than would occur with a true UART when the delay feature is enabled. This timer is also used to delay data transfer from THR Register to Z80189 TSR buffer in double buffer mode.

DS971890301

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PRELIMINARY

TRANSMIT AND RECEIVE TIMERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

765 43210

11111111

Receiver Time Constant

Figure 88. Receiver Time Constant Register

(Z180 MPU Address XXFB)

When the Z180 MPU writes to the Receive Buffer register and the Receive Timer is enabled, the Receive Timer is loaded with the Receiver Time Constant, the timer is

16550 MIMIC REGISTERS

The Z80189 contains a register set for interfacing with the PC/XT/AT. The registers are:

Receiver Buffer Register Transmit Holding Register Interrupt Enable Register Interrupt Identification Register Line Control Register Modem Control Register Line Status Register Modem Status Register Scratch Register Divisor Latch Least Significant/Most Significant Bytes FIFO Control Register MIMIC Modification Register

enabled and counts down to zero. When the timer reaches zero, the Data Ready bit in the Line Status Register is set. As with the Transmit Timer the Data Ready bit is also mirrored. Immediately upon a write to the Receive Buffer, the mirrored bit is set to let the Z180 MPU know that the byte has already been written. If the timer is not enabled, then both Data Ready bits are set immediately upon a write to the Receive Buffer. The FIFO mode of operation is similar in that the status to the PC is always delayed by the time required for each character written to the FIFO by the Z180. The effect is that the PC will not see a FIFO trigger level or DMA request faster than would occur with a true UART when the delay feature is enabled.

Receive Buffer Register

When the Z180 has assembled a byte of data to pass to the PC/XT/AT, it places it in the Receiver Buffer Register. If the Received Data Available interrupt is enabled, then an interrupt is generated for the PC/XT/AT and the Data Ready bit is set (if the Receiver Timer is enabled, the interrupt and setting of the Data Ready bit is delayed until after the timer times out). Also, the shadow bits of the Line Status Register are transferred to their respective bits when the Z180 MPU writes to the Receiver Buffer Register (see Line Status Register Bits 1, 2, 3 and 4). This allows a simultaneous setting of error bits when the data is written to the Receiver Buffer Register. In FIFO mode, this address is used to read (PC) and write (Z180) the Receiver FIFO.

These registers are used to emulate the 16550 UART. The PC/XT/AT can access these registers just as if it was interfacing with the 16550 UART. This allows the Z80189 to be software compatible with existing Z80189 modem software.

765 43210 XXXXXXXX

Receiver Buffer Register

PC Read Only, (Address 00h, DLAB=0, R/W=Read) (Z180 MPU Write Only, Address xxF0H)

Figure 89. Receiver Buffer Register

DS971890301

Zilog

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Transmit Holding Register

When the PC/XT/AT writes to the Transmitter Holding Register, the Z80189 responds by setting the appropriate bit in the IP register and by generating an interrupt to the Z180 MPU if it is enabled. When the Z180 MPU reads this register, the Transmitter Holding register empty flag is set (if the transmitter timer is enabled, this bit is set after the timer times out). In FIFO mode of operation, this address is used to read (Z180) and write (PC) the Transmitter FIFO.

765 43210 XXXXXXXX

Transmitter Holding Register

(PC Write Only, Address 00H, DLAB=0, R/W=Write) (Z180 MPU Read Only, Address XXF0H)

Figure 90. Transmitter Holding Register

FIFO Control Register

765 43210

Bit 6 and Bit 7 RCVR trigger LSB and MSB bits

This 2-bit field determines the number of required bytes in the receiver FIFO before an interrupt to the PC occurs.

b7 b6 Trigger Level, Number of Bytes

00 01 01 04 10 08 11 14

Bit 4 and Bit 5 Reserved

Note: From the MPU side, bit 4 and bit 5 flag two sources of interrupts. Bit 5 is a FIFO interrupt, indicating that the FCR had changed; bit 4 is a Tx overrun interrupt, indicating transmit overrun. A read of the FCR from the MPU side will clear a previously set bit 4 or bit 5.

Bit 3 Reserved

Reserved for future use.

Bit 2 XMIT FIFO Reset

Setting this bit to a 1 will cause the transmitter FIFO pointer logic to be reset; any data in the FIFO will be lost. This bit is self clearing; however, a shadow bit exists that is cleared only when read by the Z180 MPU, allowing the MPU to monitor a FIFO reset by the PC.

00000000

FIFO Enable RCVR FIFO Reset XMIT FIFO Reset Reserved (Must be 0) Reserved

(Tx Overrun, MPU Only) Reserved

(FCR Write, MPU Only) RCVR Trigger (LSB)

RCVR Trigger (MSB)

PC/XT/AT Write Only, PC Address 02h Z180 MPU Read Only, MPU Address XXE9H

Figure 91. FIFO Control Register

Bit 1 RCVR FIFO Reset

Setting this bit to a 1 will cause the receiver FIFO pointer logic to be reset; any data in the FIFO will be lost. This bit is self clearing; however, a shadow bit exists that is cleared only when read by the Z180 MPU, allowing the MPU to monitor a FIFO reset by the PC.

Bit 0 FIFO Enable

The PC writes this bit to logic 1 to put the 16550 MIMIC into FIFO mode. This bit must be a 1 when writing to the other bits in this register or they will not be programmed. When this bit changes state, any data in the FIFO’s or transmitter holding and receiver buffer registers is lost and any pending interrupts are cleared.

DS971890301

Zilog

PRELIMINARY

Interrupt Identification RegisterMIMIC Modification Register

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

D6 D5 D4 D3 D2 D1 D0

00000000

Reserved - Program to Zero 16550/450 RCVR Overrun

Figure 92. MIMIC Modification Register

(Z189 MPU Write only, Address XXE9H)

Bit 7-2 Reserved. Program to zero.

Bit 1 RCVR Overrun Modification

The actual 16450/16550 device allows the last position in FIFO to be overwritten by MPU during receiver overrun condition. When this bit is enabled (programmed to 1) the last position in FIFO can be overwritten by Z180 during receiver overrun. This feature is disabled by default. When this modification is not enabled, the MIMIC will ignore any write to RBR during an overrun condition.

Bit 0 Reserved

Program to zero.

765 43210

00000000

0 if Interrupt Pending Interrupt ID Bit (0) Interrupt ID Bit (1) Interrupt ID Bit (2)

Always 0 FIFO Enabled Flag

PC/XT/AT Read Only, PC Address 02H Z180 MPU No Access

Figure 93. Interrupt Identification Register

Bit 7 and Bit 6 FIFO’s enabled

These bits will read 1 if FIFO mode is enabled on the MIMIC.

Bit 5 and Bit 4 Always read 0

Reserved bits.

Bits 3-1 Interrupt ID bits

This 3 bit field is used to determine the highest priority interrupt pending. See Table 16 for the 3-bit field descriptions.

Table 16. Interrupt Identification Field

b3 b2 b1 Priority Interrupt Source Inter. Reset Control

0 1 1 Highest Overrun, Parity, Read Line Stat. Reg.

Framing error or Break detect bits set by MPU.

0 1 0 2nd Received Data RCVR FIFO drops below

trigger level trigger level.

1 1 0 2nd Receiver Time-out Read RCVR FIFO.

with data in RCVR FIFO.

0 0 1 3rd Transmitter Writing to the

Holding Register IIR or transmitter Empty. Holding Register.

0 0 0 4th MODEM status: Reading the MODEM

CTS,DSR,RI or DCD.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 0 Interrupt Pending

This bit is logic 0 and interrupt is pending. When the PC accesses the IIR, the contents of the register and all pending interrupts are frozen. Any new interrupts will be recorded, but not acknowledged during the IIR access.

Line Status Register

765 43210

00010000

Data Ready Overrun Error Parity Error Framing Error Break Interrupt (BI) THRE TEMT Error in RCVR FIFO

PC/XT/AT Read Only, PC Address 05H Z180 MPU Read/Write Bits 6,4,3,2 MPU Address XXF5H

Figure 94. Line Status Register

Bit 2, 3, 4 Parity Error, Framing Error, Break Detect

These bits are written, indirectly, by the MPU as follows: The bits are first written to shadow bit locations when the MPU write accesses the LSR. When the next character is written to the Receiver Buffer or RCVR FIFO, the data in the shadow bits is then copied to the LSR (16450 mode) or FIFO RAM (16550 mode). In FIFO mode, the bits become available to the PC when the data byte associated with the bits is next to be read (top of FIFO). In FIFO mode, with successive reads of the receiver, the status bits will be set if an error occurs on any byte. Once the MPU writes to the Receiver Buffer or RCVR FIFO, the shadow bits are auto cleared. The register bits are cleared upon the PC reading the LSR. In FIFO mode, these bits will be set if any byte has the respective error bit set while the PC reads multiple characters from the FIFO.

Bit 1 Overrun Error

This bit is set if the Z180 MPU makes two writes to the Receiver Buffer before the PC reads the data in the Buffer (16450 mode) or with a full RCVR FIFO (16550) mode. No data will be transferred to the RCVR FIFO under these circumstances. This bit is reset when the PC reads the Line Status Register.

Bit 7 Error in RCVR FIFO

In 16450 mode, this bit will read logic 0. In 16550 mode, this bit is set if at least one data byte is available in the FIFO with one of its associated error bits set. This bit will clear when there are no more errors (or break detects) in the FIFO.

Bit 6 Transmitter Empty

This bit must be set or reset by the MPU by a write to this register bit. If Double Buffer Mode is enabled this bit is set automatically by hardware whenever both THR buffer and TSR is empty.

Bit 5 Transmitter Holding Register Empty, THRE

This bit is set to one when either the THR has been read (emptied) by the MPU (16450 mode) or the XMIT FIFO is empty (16550 mode). This bit is set to 0 when either the THR or XMIT FIFO become non-empty. A shadow bit exists so that the register bit setting to 1 is delayed by the Transmitter Timer if enabled. The MPU when reading this bit will not see the delay. Both shadow and register bits are cleared when the PC writes to the THR of XMIT FIFO.

Note: The THRE bit is forced to 0 in the PC side to prevent THR overruns when /HALT is asserted (Powerdown Mode) and bit 3 (/INTO assertion on MIMIC access feature) is set. When the MIMIC comes out of powerdown (/HALT deasserted), the THRE bit resumes normal functionality.

Bit 0 Data Ready

This bit is set to 1 when received data is available, either in the RCVR FIFO (16550 mode) or Receiver Buffer Register (16450 mode). This bit is set immediately upon the MPU writing data to the Receiver Buffer or FIFO if the Receiver Timer is not enabled but is delayed by the timer interval if the Receiver Timer is enabled. For MPU read access, a shadow bit exists, so that the MPU does not see the delay the PC does. Both bits are cleared to logic zero immediately upon reading all the data in either the Receiver Buffer or FIFO.

Interrupt Enable Register

765 43210

00000000

Bit 0 Received Data Available Int. Bit 1 THRE Interrupt Bit 2 Receiver Line Status Int. Bit 3 Modem Status Interrupt Bit 7,6,5,4 always 0

PC/XT/AT Read/Write, PC Address 01H Z180 MPU Read Only, Z180 MPU Address XXF1H

Figure 95. Interrupt Enable Register

DS971890301

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Interrupt Enable Register (Continued)

Bits 7,6,5,4 Reserved

These bits will always read 0 (PC and MPU)

Bit 3 Modem Status IRQ

If bits 0,1,2 or 3 of the Modem Status Register are set and this enable bit is a logic 1, then an interrupt to the PC is generated.

Bit 2 Receiver Line Status IRQ

If bits 1,2,3 or 4 of the LSR are set and this enable bit is a logic 1, then an interrupt to the PC is generated.

Bit 1 Transmitter Holding Register Empty IRQ

If bit 5 of the LSR is set and this enable bit is a logic 1, then an interrupt to the PC is generated.

Bit 0 Received Data Available IRQ

If bit 0 of the LSR is set or a Receiver Timeout occurs and this enable bit is a logic 1, then an interrupt to the PC is generated.

Line Control Register

Bit 6-Bit 0

These bits do not affect the Z80189 directly; however, they can be read by the Z180 MPU and the 16550 MIMIC modes can be emulated by the Z180 MPU.

Modem Control Register

765 43210

00000000

DTS RTS Out 1 Out 2 Loop Reserved

PC/XT/AT Read/Write, PC/XT/AT Address 4H Z180 MPU Read Only, Z180 MU Address XXF4H

Figure 97. Modem Control Register

765 43210

00000000

Word Length Sel. Number of Stop Bits Parity Enable Even Parity Sel. Stick Parity Set Break DALB

PC/XT/AT Read/Write, PC/XT/AT Address 3H Z180 MPU Read Only, Z180 MU Address XXF3H

Figure 96. Line Control Register

Bit 7 Divisor Latch Access Bit (DALB)

This bit allows access to the divisor latch by the PC/XT/AT. If this bit is set to a one, access to the Transmitter, Receiver and Interrupt Enable Registers is disabled, and when an access is made to address 0, the Divisor Latch Least Significant byte is accessed and if an access is made to address 1, the Divisor Latch Most Significant byte is accessed.

Bit 7-5 Reserved

Reserved for future use, always 0.

Bit 4 Loop

When this bit is set to a one then:

RI = Out 1 DCD = Out 2 DSR = DTR CTS = RTS

Emulation of the loop back feature of the 16550 UART must be done by the Z180 MPU except for the above conditions.

Bit 3 Out 2

This bit controls the state on the active HINTR pin if bits 2 and 1 of the MIMIC Master Control Register are a 10. Or else it can be read by the Z180 MPU.

Bit 2-Bit 0

These bits have no direct control of the 16550 MIMIC interface and the Z180 MPU must emulate the function if it is to be implemented.

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Zilog

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Modem Status Register

765 43210 00000000

DCTS DDSR TERI DDCD CTS DSR RI DCD

PC/XT/AT Read Only, PC/XT/AT Address 6H Z180 MPU Read/Write Bits 7-4, Z180 MPU Address XXF6H

Figure 98. Modem Status Register

Bit 7 Data Carrier Detect

This bit must be written by the Z180 MPU.

Bit 6 Ring Indicator

This bit must be written by the Z180 MPU.

Scratch Register

765 43210 XXXXXXXX

Scratch Register

PC/XT/AT Read/Write, PC/XT/AT Address 07H Z180 MPU Read Only, Z180 MPU Address XXF7H

Figure 99. Scratch Register

Bits 7-0 Scratch Register

This register is used by the PC/XT/AT programmer for temporary data storage. The Z180 MPU is able to read this register. If the PC/XT/AT writes to this register, no interrupt to the Z180 MPU is generated.

Divisor Latch (LS)

765 43210

XXXXXXXX

Divisor Latch (LS)

PC/XT/AT Read/Write, PC/XT/AT Address 00H and DLAB = 1 Z180 MPU Read Only, Z180 MPU Address XXF8H

Bit 5 Data Set Ready

This bit must be written by the Z180 MPU.

Bit 4 Clear to Send

This bit must be written by the Z180 MPU.

Bit 3 Delta Data Carrier Detect

This bit is set to a one whenever the Data Carrier Detect bit changes state. This bit is reset when the PC/XT/AT reads the Modem Status Register.

Bit 2 Trailing Edge Ring Indicator

This bit is set to a one on the falling edge of the Ring Indicator bit. This bit is reset when the PC/XT/AT reads the Modem Status Register.

Bit 1 Delta Data Set Ready

This bit is set to a one whenever the Data Set Ready bit changes state. This bit is reset when the PC/XT/AT reads the Modem Status Register.

Bit 0 Delta Clear To Send

This bit is set to a one whenever the Clear To Send bit changes state. This bit is reset when the PC/XT/AT reads the Modem Status Register.

Figure 100. Divisor Latch (LS)

Bit 7-0 Divisor Latch Most Significant (MS)

This register contains the low order byte of the Baud rate divisor. Writing to this register with the PC/XT/AT will generate an interrupt to the Z180 MPU. It can then read the Baud rate divisor and set up the application.

Divisor Latch (MS)

765 43210 XXXXXXXX

Divisor Latch (MS)

PC/XT/AT Read/Write, PC/XT/AT Address 01H and DLAB = 1 Z180 MPU Read Only, Z180 MPU Address XXF9H

Figure 101. Divisor Latch (MS)

Bit 7-0 Divisor Latch Most Significant (MS)

This register contains the high order byte of the Baud rate divisor. Writing to this register with the PC/XT/AT will generate an interrupt to the Z180 MPU. It can then read the Baud rate divisor and set up application.

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PC DMA Mailbox

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

General Description

The concept behind the PC DMA Mailbox Registers is to provide a path for the PC DMA data transfer separate from the MIMIC COM Port. Commands and data flow over the COM Port, while the DMA path is reserved for other purposes. The PC DMA Mailbox Register functionality will require control registers which will allow PC DMA data transfer between the PC memory and for example, a modem speaker/microphone codec. Note that the transfer will be driven by the PC Host DMAs. This feature only allows for the handshaking and data path for the PC Host DMAs.

The host (PC) DMA channels will use the following four Z189 pins for the PC DMA Mailbox feature. Each pair of pins are individually selectable:

PC DMA MAILBOX BIT FUNCTIONS

HDRQ0 Host DMA request 0, Z189 output,

active high, high-Z control

/HDACK0 Host DMA acknowledge 0, Z189 input, active low

HDRQ1 Host DMA request 1, Z189 output, active high, high-z control

/HDACK1 Host DMA acknowledge 1, Z189 input, active low

The pins labeled as HDRQ0 and HDRQ1 are asserted by the Z180 to signal the PC HOST of a DMA request. The pins labelled /HDACK0 and /HDACK1 are asserted by the PC to signal a PC DMA access. Dual request/acknowledge pairs are provided to interface with two PC DMA channels. The PC Mailbox channels are independent and can be used simultaneously or individually for jumperless DMA channel selection.

HDREQ. Host DMA request bit, default value = 0

Two bits will serve to request a PC HOST DMA access. When this bit is set and the Host DMA channel is enabled (HDMAE=1), the corresponding HDRQ pin will be asserted high. Z180 software sets this bit (OUT0 instruction) to request a DMA transfer, and Z189 hardware clears the bit when the byte transfer is complete. Z180 software can also clear the bit. The Z180 will be able to read the bit (IN0 instruction) to indicate that the transfer has occurred.

I/O address of XXD2h (HMC register) contains a request bit for each DMA channel (bit 4 and bit 5 of the HMC register). Write enable bits are provided to simplify code (read-modify-write cycles not required).

HDMAE Host DMA enable default=0, HDRQ is tri-stated

Two bits will serve to enable the dual DMA channels request/acknowledge pairs. When the HDMAE1 bit is set, the output will become fully driven, otherwise (HDMAE1 bit is reset) the HDRQ1 will be tri-stated. When the HDMAE0 bit is set the HDRQ0 output will become fully driven, otherwise, the HDRQ0 output will be tri-stated.

I/O address XXD2h is assigned the HMC register. Bits 0 and 1 of the HMC register are respectively assigned HDMAE0 and HDMAE1.

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PC MAILBOX DATA REGISTERS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

HDMAT0 Host DMA Transmit Register 0,

Z180 Read Only, PC Write Only

HDMAT1 Host DMA Transmit Register 1,

Z180 Read Only, PC Write Only

HDMAR0 Host DMA Receive Register 0,

Z180 Write Only, PC Read Only

HDMAR1 Host DMA Receive Register 1,

Z180 Write Only, PC Read Only

There are four separate 8-bit mailbox registers available for DMA data. The I/O address for the mailbox registers will be XXDOH for Mailbox 0 and XXD1H for Mailbox 1. Note that there are separate registers for read and write access. The mailbox register can latch data from the host data bus HD[0:7] and is readable by the Z180 using IN0 a, (DOH) or IN0 a, (D1H). Data can be written into the mailbox registers using the OUT0 (DOH), a or OUT0 (D1H), a and can output its contents onto HD [0:7} during a PC HOST DMA access.

Note: The following is a description of other Z189 signals relevant in a PC DMA Mailbox access.

– The /HDDIS signal will go low during a PC DMA Read

access (selected /HDACK and /HRD going low).

– The /HCS pin will not asserted low during a PC DMA

Mailbox access (/HDACK active) if the HDRQ/HDACK channel is enabled.

3. Z189 hardware forces HDRQ inactive low on the leading (falling) edge of /HWR during the /HDACK cycle. Note that the HDREQ register bit is not to be cleared yet, since the DMA cycle has not yet completed.

4. The PC places valid data on the ISA bus (HD[0:7] and asserts /HWR low.

5. Z189 hardware latches data into the HDMAT register on the trailing (rising) edge of /HWR while /HDACK is still active low. On this same edge, hardware clears the HDREQ register bit.

6. Z180 software polls the HDREQ bit until it's 0, and then can input the data byte from HDMAT. The polling of the HDREQ bit is used to indicate when the PC DMA Write has been completed. The PC software program should program its DMA controller to stop DMA at the end of valid data or when commanded by the application. When the Z180 software sets HDREQ, but doesn't see the HDREQ bit automatically cleared within a reasonable time (because /HDACK remains inactive high), then software can stop the PC DMA write by resetting the HDREQ bit.

7. Messages on the COM Port confirm that the PC DMA write operation is complete. Z180 software clears HDREQ, then clears HDMAE to disable host DMA.

PC DMA Read

PC DMA Write

Through commands exchanged over the MIMIC COM Port, PC software and the Z180 agree to configure DMA for a PC DMA write, in which data flows from PC memory to, for example, a modem's speaker codec. The PC sets up its 8237 DMA controller in auto-initialize mode to assure that data is always available whenever the modem makes a DMA request. The Z180 clears HDREQ and sets HDMAE, forcing HDRQ low.

The PC DMA Write proceeds as follows:

1. Z180 software writes a 1 to the HDREQ bit, causing the HDRQ pin to go active High.

2. The rising edge of HDRQ causes the 8237 DMA controller to begin a memory-read, I/O-write DMA bus cycle on the ISA bus at the end of the current PC bus cycle. The PC asserts /HDACK low to acknowledge the DMA request.

PC DMA Read is almost the same as a PC DMA Write, but the data flows the other direction through the HDMAR register.

Through commands exchanged over the MIMIC COM Port, PC software and the Z180 agree to configure DMA for a PC DMA Read, in which data flows from, for example, a modem's microphone codec to PC memory. The PC sets up its 8237 DMA controller in auto-initialize mode to assure that there is always buffer space available whenever the modem makes a DMA request. The Z180 clears HDREQ and sets HDMAE, forcing HDRQ low.

The PC DMA Read proceeds as follows:

1. Z180 software outputs the data byte to HDMAR, where it is latched.

2. Z180 software writes a 1 to the HDREQ bit, causing the HDRQ pin to go active high.

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PRELIMINARY

PC MAILBOX DATA REGISTERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

3. The rising edge of HDRQ causes the 8237 DMA controller to begin an I/O-read, memory-write DMA bus cycle on the ISA bus at the end of the current PC bus cycle. The PC asserts /HDACK low to acknowledge the DMA request.

4. Z189 hardware forces HDRQ inactive low on the leading (falling) edge of /HRD during the /HDACK cycle. Note that the HDREQ register is not to be cleared yet, since the DMA cycle has not completed.

5. The PC asserts /HRD low while /HDACK is still active low, causing Z189 hardware to enable the latched HDMAR byte onto HD[0:7].

6. While Z189 hardware holds valid data on the ISA bus, the PC does its memory-write half of the DMA cycle. On the trailing (rising) edge of /HRD, Z189 hardware disables the output of the HDMAR register, putting HD[0:7] in high impedance state. On this same edge, hardware clears the HDREQ register bit. Note: /HDDIS will go low while the HDMAR register is accessed on the ISA bus.

7. Z180 software polls the HDREQ bit until it's 0, then continues with step 0 for the next byte.

PC DMA Read will not be stopped as with the case for PC DMA Write if the HDREQ handshake is not met. If software fails to see HDREQ reset soon after making the DMA request (because /HDACK remains inactive high), Z180 software should clear HDREQ and HDMAE and configure the data pump to stop the PC DMA Read.

Clear HDREQ bit:

Reset OR I/O write 0 to HDREQ bit in HMC register OR (Rising edge of (/HRD and /HWR) while /HDACK=0)

Drive HDRQ pin active high:

HDREQ bit = 1 while HDMAE=1

Drive HDRQ pin inactive low:

Reset OR /HDACK=0 OR HDREQ bit = 0

Latch PC DMA Write data to HDMAT register:

HDMAE=1 AND /HDACK=0 AND /HWR=0

Drive PC DMA Read data from HDMAR register:

HDMAE=1 AND /HDACK=0 AND /HRD=0

Selectable DMA Channels

The Z189 features jumperless selection of PC DMA channels. On the 8-bit PC/XT bus, DMA channels 0 and 3 are generally available, therefore reference designs may connect to those. 2 HDREQ bits and 2 HDMAE Enable bits are used to enable which PC DMA Channel is to be implemented. In addition, there are two additional bits which allow for the multiplexing of PC DMA Mailbox functions with Bus Mastering and Z180 peripheral functions.

Logic Equations for PC DMA Read/Write

This section summarizes the significant events for PC DMA Read/Write that was explained in the previous sections. This section can be used as a quick check of the circuit implementation.

Set HDREQ bit:

I/O write 1 to HDREQ bit in HMC register.

PC DMA Mailbox Pin Designations

The four request/acknowledge pins will be designated as follows, and are assigned the following QFP pins as shown below:

HDRQ, pin 50, output (mux with RTS0) /HDACK0, pin 43, input (mux with CKA0 and /DREQ0) HDRQ1, pin 97, output (mux with /BUSACK) /HDACK1, pin 98, input (mux with /BUSREQ)

DS971890301

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PRELIMINARY

PC MAILBOX DATA REGISTERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

765 43210

11000000

Figure 102. Host DMA Mailbox

Control Register, HMC

(Z180 MPU Read/Write Address XXD2H)

0 = HDRQ0 Tri-State 1 = HDMA Enable

0 = HDRQ1 Tri-State 1 = HDMA Enable

HDRQ /HDACK0, CKA0//DREQ0, /RTS0 0 = HDRQ0, /HDACK0 Select 1 = /RTS0, CKA0//DREQ0 Select

HDRQ1, /HDACK1, /BUSACK, /BUSREQ 0 = HDRQ1, /HDACK1 Select 1 = /BUSACK, /BUSREQ Select

HDREQ0 (DMA request 0) HDREQ1 (DMA request 1)

Revision Data Avail Write Enable HDREQ0

Revision Data Avail Write Enable HDREQ1

Bit 5 HDREQ1 Bit

When Mailbox 1 is multiplexed and enabled (HDMAE1=1), setting this bit will cause the HDRQ1 pin to go active high, which puts out a request to the PC for a DMA transfer. Z189 hardware clears this bit when byte transfer is complete. This bit is disabled upon reset. This bit can also be reset to force the HDRQ1 pin to inactive low. Note that Bit 7 must be set to modify HDREQ1.

Bit 4 HDREQ0 Bit

When Mailbox 0 is multiplexed and enabled (HDMAE0=1), setting this bit will cause the HDRQ0 pin to go active high, which puts out a request to the PC for a DMA transfer. Z189 hardware clears this bit when byte transfer is complete. This bit is disabled upon reset. This bit can also be reset to force the HDRQ0 pin to inactive low. Note that Bit 6 must be set to modify HDREQ0.

Bit 3 HDRQ1/HDACK1, /BUSACK /BUSREQ

This bit selects the multiplexing that will occur between the HDRQ1//BUSACK and the /HDACK1/BUSREQ pins. If this bit is set to 0, the HDRQ1 and /HDACK1 functions are enabled for this pin. Otherwise, if this bit is set to 1, the /BUSACK and /BUSREQ functions are enabled for this pin. This bit is reset to 0.

Bits 7 Write Enable HDREQ1 (Write only) Revision Data Available (Read only)

Set this bit whenever setting/resetting the HDREQ1 bit. When this bit is written with 1, bit 5 will be written into the HDREQ bit and bits 0-3 are ignored. When this bit is written with zero, bits 0-3 can be written and bit 5 is ignored. Note that this bit does not change the write access to bits 4 and

6. The Write Enable is not latched and must be set for each

HDREQ1 write.

When bit 7 is read it is set upon powerup and becomes reset during the 1st read of the HDMAT1 register.

Bits 6 Write Enable HDREQ0 (Write only)

Set this bit whenever setting/resetting the HDREQ0 bit. When this bit is written with 1, bit 4 will be written into the HDREQ0 bit and bits 0-3 are ignored. When this bit is written with zero, bits 0-3 can be written and bit 4 is ignored. Note that this bit does not change the write access to bits 5 and 7. The Write enable is not latched and must be set for each HDREQ0 write.

When bit 6 is read, it indicates the availability of the revision data in the Host DMA transmit register (HDMAT0). When the revision data is read by the Z180 CPU, this bit will become reset and the revision data will no longer be available in the HDMAT0 register.

Bit 2 HDRQ/HDACK0, /RTS0 CKA0//DREQ0

This bit selects the multiplexing that will occur between the HDRQ0//RTS0 and the /HDACK/CKA0//DREQ0 pins. If this bit is set to 0, the HDRQ and /HDACK0 functions are enabled for this pin. Otherwise, if this bit is set to 1, the CKA0//DREQ0 and /RTS0 functions are enabled for this pin. This bit is reset to 0.

Bit 1 HDMAE1 bit

When this bit is set to 1, it allows Mailbox 1 to request a PC DMA cycle given that the Mailbox 1 pins are multiplexed (bit 4=1). When this bit is cleared to 0, the HDREQ1 is tristated if Mailbox 1 pins are multiplexed. When this bit is cleared, the HDMAT1 can be used to store HOST OUTPUT MAILBOX DATA.

Bit 0 HDMAE0 bit

When this bit is set to 1, it allows Mailbox 0 to request a PC DMA cycle given that the Mailbox 0 pins are multiplexed (bit 4=1). When this bit is cleared to 0, the HDREQ0 is tristated if Mailbox 0 pins are multiplexed.

DS971890301

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PRELIMINARY

PC DMA MAILBOX DATA REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

765 43210

10010001

Figure 103. Host DMA Transmit Register, HDMAT0

(Z180 MPU Read Only Address XXD0H)

(PC Write Only)

Note: 91hex is defaulted into this register to indicate revision (9 for Z189 and 1 for 1st revision). Once the revision data is read by the Z180 CPU, bit 6 of the HMC register (Revision Data Avail bit) will be read as zero.

765 43210

00000000

Figure 104. Host DMA Receive Register, HDMAR0

(Z180 MPU Write Only Address XXD0H)

(PC Read Only)

765 43210 00000000

Figure 105. Host DMA Transmit Register, HDMAT1

(Z180 MPU Read Only Address XXD1H)

(PC Write Only)

HDMAT1 can also be used as a HOST OUTPUT MAILBOX DATA REGISTER. Refer to Host Output Mailbox function for details.

765 43210

00000000

Figure 106. Host DMA Receive Register, HDMAR1

(Z180 MPU Write Only Address XXD1H)

(PC Read Only)

HOST INPUT/OUTPUT MAILBOX ENHANCEMENTS

The purpose of Host I/O Mailbox is to provide an additional data path between PC HOST and Z80189 in a Modem Control Application. This is required in order to accommodate transfer of data other than data (flows through COM Port) or audio (flows through PC DMA MAILBOX). An example implementation of this feature is described below:

– PC HOST controlled COM Port selection. In a Psuedo

"Plug & Play" environment, the PC BIOS will assign a modem to a COM Port address upon powerup. Therefore, the Modem will need to "listen" to the PC bus for BIOS calls that query the existence of a modem card.

In order to facilitate the feature listed above, a communication path needs to be available between a PC BIOS and Modem PRIOR to the selection of COM Port, DMA, or IRQ selection.

The modem will then need to reply and output information on its capabilities and requirements. The PC BIOS will then assign the Modem to a COM Port and interrupt such that there are no resource conflicts.

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Enhancement Detail

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

PC HOST Address Selection. There are a total of 4 registers addresses that are accessible by the PC HOST. They are as follows:

Address HA9-HA2 programmable

Function HA1 HA0

Host Output Register 0 0 0 Host Output/Input Register 1 0 1 Host I/O Status Register 1 0 *Host Output to HDMAT1 Register 1 1

The HA9-HA2 is programmable by writing the contents into Port A Data Register. The PC HOST access will occur during a PC HOST input/output cycle at the programmed address range (/HRD or /HWR=0, HAEN=0, PA[9:2]=PADATA[7:0]). NOTE: PADATA SHOULD BE

WRITTEN WITH THE ADDRESS RANGE PRIOR TO ENABLING THIS FEATURE.

* If the Host DMA Mailbox 1 function is disabled (bit 1 of HMC register is zero), a Host write in the programmed Mailbox range with HA1,0=1,1, will cause the host data to be latched into the HDMAT1 register. This can be used as an auxiliary host output register. Note that a host read from this address is invalid.

765 43210

00000000

Figure 107. Host Output Register 0 (HOR0)

(180 MPU Read Only Address XXD3H)

(PC Host Read/Write HA9-2 (PADATA) + 00b)

765 43210

00000000

765 43210

00000000

Unlock Bit Host Output Register 0

Data Available Host Output Register 1

Data Available Host Input Register 1

Data Available Auxilliary Bits Host I/O Mailbox Enable

Figure 110. Host I/O Status Register (HIOS)

(180 MPU Read/Write Address xxD5H)

(PC Host Read Only HA9-HA2 (PADATA) + 10b)

Bit 7.

Host I/O Mailbox Enable.

The Z180 must write a logic one to this bit to enable the Host I/O Mailbox. When this bit is at zero (default), Host accesses are disabled. This bit is only writable by the Z180, but is readable by both Z180 and PC Host. When this bit is zero, registers D3, D4 and D5 cannot be read or written except for a write to the enable bit in register D5 bit 7. Also, when this bit is zero the Host side is not accessible. Once this bit is set, all registers become visible to the Z180 and the Host.

Note: The PADATA should be programmed with HA9:HA2 address range prior to setting this bit. This bit should be programmed as zero when the COM Decode Mux (CDR bit

0) is disabled.

Bits 6-4.

Auxiliary bits.

these bits can be written by the Z180 and can be read by both the PC HOST and the Z180. Note that the PC HOST cannot write to these bits. The Auxillary Bits are zero by default and have no function other than to serve as scratch bits for the HOST I/O Mailbox.

Figure 108. Host Output Register 1 (HOR1)

(180 MPU Read Only Address XXD4H)

(PC Host Write Only HA9-2 (PADATA) +01b)

765 43210

00000000

Figure 109. Host Input Register 1 (HIR1)

(180 MPU Write Only Address XXD4H)

(PC Host Read Only HA9-2 (PADATA) + 01b)

DS971890301

Bit 3.

Host Input Register 1 Data Available.

This bit be-

comes set when the Z180 writes to the Host Input Register

1. A PC Host read of the Host Input Register 1 will cause this bit to clear. This bit cannot be set unless the Host I/O Mailbox enable bit is set.

Bit 1.

Host Output Register 0 Data Available.

This bit becomes set when the PC Host writes to the Host Output Register 0. A Z180 read of the Host Output Register 0 will cause this bit to clear. This bit cannot be set unless the Host I/O Mailbox enable bit is set.

Zilog

PRELIMINARY

HOST INPUT/OUTPUT MAILBOX ENHANCEMENTS (Continued)

Bit 0.

Unlock Bit.

PC Host Write to Address 0FBHex will cause this bit to set. A PC host write to address 0F9hex will cause this bit to reset. The data written to these registers will NOT be stored. A read access or access with HAEN=1 will NOT cause this bit to toggle. Note that this bit has no function other than a status bit (there is no locking or unlocking caused by the state of this bit). The state of the unlock bit is not controlled by the Host I/O Mailbox bit. Any I/O write to FB will set the bit and a write to F9 will clear it regardless of the state of the Host I/O Mailbox enable bit. Note that the data written to 0FBhex or 0F9hex will not be stored by the Z189.

When the Host I/O Mailbox is enabled, a

If COM Port decode is disabled and COM Port decode mux is enabled (default), COM Decode Pins HA9-HA3, HAEN are ignored inputs. If HC1 is forced low the MIMIC Data latch will be forced open. Therefore, care should be taken that the HC1//HCS pin is NEVER connected directly to logic high or low, when COM Port Decode is disabled.

/HCS pin can also be programmed as an output for debug purposes. When the /HCS Force bit (Bit 7 in the COM Port Decode Register) is enabled, the /HCS pin will be asserted low whenever the MIMIC is being accessed by the PC host. This feature is only available when the COM Port Decode is enabled.

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

I/O Chip Select w/Prog. Range

The Z80187 has two I/O Chip Selects labelled /IOCS1 and /IOCS2. The /IOCS1 will have same functionality as the Z80182’s /IOCS pin (multiplexed with IEO and active during I/O accesses between ranges XX80H to XXBFH). The IOCS pins will be asserted if /IORQ is active, /M1 is inactive, and address compare is within range.

The Z80189 also has a secondary IOCS labeled /IOCS2. This pin will be active for I/O accesses in the range of XXC0H - XXC7H or XXC8H-XXCFH. The /IOCS2 pin will be multiplexed over the E pin when enabled.

COM Port Decode

COM Port decode allows MIMIC to be selected when PC address HA9-HA3 specifies a selected COM port address range by HC pins 1 and 2 (selects COM Port address 1-4).

HC1 and HC2 can be read in software and program an appropriate comport range for the decode circuitry. HC1 and HC2 can also be used for general input purposes. The status of these pins can also be read when the COM Decode Mux is disabled.

A dual HINTR option will provide two MIMIC Interrupt requests to the HOST. HINTR1 will be asserted during a MIMIC interrupt request when COM Decode is configured for COM 1 & 3. HINTR2 will be asserted during a MIMIC interrupt request when COM Decode is configured for COM 2 & 4. The unasserted HINTR line will be tri-stated.

Note that during initialization, the COM Decode Register must be written to before the System Configuration Register.

Single Baud Rate Generator

A Baud Rate Generator is included to provide emulation timing for the MIMIC device. This BRG is very similar to ESCC BRG in functionality. There are 2x8 bit registers to program the clock divider. The input to the BRG is the PHI clock output of the S180 core.

The time constant required for a specific bit rate is as follows:

Time constant (decimal) = (PHI freq. / (2*baud rate))-2

This formula is exactly the same as used in the ESCC.

The output of the BRG is directly connected to MIMIC emulation counter input.

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Baud Rate Generator Register

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The following registers are used to store BRG constant. The timer is enabled after setting bit 0 of IOBRG register. Design is such that on-the-fly modification of registers do not cause irregular BRG output.

765 43210 11111111

Lower Byte of

Time Constant

Figure 111. BRGL Baud Rate Generator Low

(Address XXE0H) Default 00 Hex

IOBRG Register

The following register handles the IOCS feature and MIMIC BRG. IOBRG-IOCS & BRG enable (Address XXD6H) Default 04 hex.

765 43210

00000100

BRG Enable /IOCS2 Range

1 = I/O Access between xxC0h-xxC7 0 = I/O Access between xxC8h-xxCF

/IOCS2 Enable /INTO Assertion of

MIMIC Access Reserved as 0

Figure 113. IOBRG-IOCS and BRG Enable

(Address XXD6H)

Bits 4-7 Reserved

Bit 3 /INT0 assertion on MIMIC access. When this bit R/W is enabled, and the /HALT is active (power-down)

any HOST access to the MIMIC will cause a low edge. Since this interrupt source has no vector, /INT0 MODE 1 must be used when enabling this mode. This is disabled on power-up. /INT0 assertion is released when /HALT is deasserted.

765 43210

11111111

Upper Byte of

Time Constant

Figure 112. BRGH Baud Rate Generator High

(Address XXE9H) Default 00 Hex

Note: The THRE bit is forced to 0 on the PC side to prevent THR overrun during powerdown modes when this feature is enabled. When the MIMIC comes out of power-down, THRE resumes normal functionality.

Bit 2 /IOCS2 enable

When set, IOCS2 is muxed over E pin. This is enabled on reset.

Bit 1 /IOCS2 range. R/W When set, IOCS2 is active during I/O accesses

between XXC0H-XXC7H. When reset, IOCS2 is active during I/O accesses between XXC8H-XXCFH. This is disabled on power-up.

Bit 0 BRG enable. When set, R/W the MIMIC BRG begins counting down to gener-

ate a programmed square wave to the MIMIC emulation timers. This is disabled on power-up.

Note: When waking from Standby Mode using a PC-THR write, the THRE bit will not reset until clock is stabilized. This may cause a THR overrun. Therefore, data integrity cannot be guaranteed. Care should be taken so that standby mode is only used when data integrity is not essential.

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PRELIMINARY

HOST INPUT/OUTPUT MAILBOX ENHANCEMENTS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The register that handles and enables COM port decode and multiplexing is as follows:

76543210

00000001

COM Port Decode MUX State of HC1 (Read Only) State of HC2 COM Port Decode Selection

Bit 4 3

0 0 COM 1 (3F8-3FF) Default 0 1 COM 2 (2F8-2FF) 1 0 COM 3 (3E8-3EF) 1 1 COM 4 (2E8-2EF)

COM Port Decode Enable Dual HINTR Reserved as 0

Figure 114. CDR - COM Decode Register

(Address XXD7H)

CDR - COM Decode Register (Address XXD7H) default 01hex

Bit 0 COM Port Decode Mux. When set, COM Port R/W Decode pins (HA9-HA3, HAEN HC1-2) are

enabled. This is set on default. Refer to multiplexing section for further detail.

Bit <1-2> Read only registers that specify the state of

HC1 and HC2 input pins when COM Port select feature is enabled in bit 0.

Bit 1 represents HC1 input. Bit 2 represents HC2 input. Since HC1 is multiplexed with /HCS, care should be taken that if COM Port Decode is disabled, /HCS is not forced low.

Bit <3-4> COM Port decode selection. These two bits

are used to select COM Port decode 1-4 as

R/W follows:

decoder during a PC-DMA cycle. This circuitry is not used when COM Port Decode (bit 5) is disabled.

HA2-HA0 are used to select between internal MIMIC registers.

Bit 5 COM Port Decode enable. When this bit R/W is set, HA3-HA9 inputs are used for COM Port

Decoder. The MIMIC will be accessible given that the address inputs HA3-HA9 are within the range programmed by bits 3 & 4 when HAEN is active low.

Please refer to MULTIPLEXING section for details on pin HA3-HA9 muxing. This is disabled on reset. When disabled, the COM Port Decode inputs are still treated as inputs, but have no affect on MIMIC operation.

Bit 6 Dual HINTR. When this bit is set, the R/W HINTR2 output will be asserted for MIMIC

interrupt requests when configured for COM 2 & 4. HINTR1 output will be asserted for MIMIC interrupt requests when configured for COM 1 & 3. When disabled, HINTR2 is always inactive (tri-stated) while HINTR1 is active for all MIMIC interrupt requests. This is disabled on reset (HINTR2 is tri-state on power-up).

Note that the unselected HINTR line will be tristated while the active HINTR line will be driven as per the MIMIC Master Control Register

Bit 7 /HCS Force Bit. When Bit 0 and Bit 5 of this

register is set to 1 (COM Decode Mux and Logic Enabled), it forces the /HCS signal to be exported out of the /HCS/HC1 pin. /HCS output is asserted when HA3-HA9 is within the boundaries programmed by bits 3-4 of CDR (regardless of /HRD and /HWR). /HCS is NOT asserted for PC DMA Mailbox accesses. If this bit is zero (default), the /HCS/HC1 pin becomes an input.

Bit 4 Bit 3

0 0 COM 1 (3F8-3FF) default 0 1 COM 2 (2F8-2FF) 1 0 COM 3 (3E8-3EF) 1 1 COM 4 (2E8-2EF)

MIMIC access will only be allowed if inputs HA9HA3 reflect the above address ranges and HAEN is deasserted. HAEN is used to disable the COM

Note: The /HCS/HC1 pin is tied to both /HCS function and HC1 functions simultaneously when bit 7 is reset to zero. Therefore, MIMIC access is disabled until the first System Configuration Register Write on COM Decode (bit 5) is enabled. This mechanism prevents accidental bus contention if /HCS/HC1 pin is pulled low.

Note: The COM Decode Register must be written first, prior to the System Configuration Register during initialization.

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PRELIMINARY

Z189 MISCELLANEOUS CONTROL AND INTERFACE REGISTERS

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

The Z80189 has the same capability of the Z180 MPU. Some extra I/O registers have been added to the Z180 MPU to interface with the Parallel ports, COM Port Decode and the 16550 MIMIC interface. A System Configuration

765 43210

11100111

Register is located at the Z180 MPU I/O Address %EF which determines the current operating mode. This register must be WRITTEN before the MIMIC is enabled.

Reserved as 1 MIMIC/Port A

0 = Port A 1 = MIMIC Data

Borrow 0 = Z80180 1 = 16550 MIMIC

Disable ROMs 0 = /ROMCS Enabled 1 = /ROMCS Disabled

DOUT 0 = No Data Out 1 = Data Out

Port PB4-PB0 Select 0 = ASCI Channel 0 Function 1 = PB4-PB0 Selected

Port PB7-PB5 Select 0 = ASCI Channel 1 Function 1 = PB7-PB5 Selected

Port C Read Select 0 = From Output Pad 1 = From Input Pins

Figure 115. System Configuration Register

(Z80180 MPU Address XXEFH)

Note: The COM Decode Register should be written prior to writing to this register.

Bit 7 Port C read

When this bit is set, a read from Port C will return value of logic state on Port C. When this bit is reset, a read from Port C will return the contents of Port C output pads (last value

Bit 5 PB4-PB0 Select

When this bit is set Port B bits 4-0 are multiplexed over ASCI 0 functions. When this bit is reset ASCI functions are active.

output on port C). This bit is not relevant when Port C is programmed for output.

Bit 4 D

ROM Emulator Mode Enable

DOUT

When this bit is set to a 1, the Z182 is in “ROM emulator

Bit 6 PB7-PB5 Select

When this bit is set Port B bits 7-5 are multiplexed over ASCI 1 functions. When this bit is reset ASCI 1 functions are active.

mode”. In this mode, bus direction for certain transaction periods are set to the opposite direction to export internal bus transactions outside the Z80189. This allows the use of ROM emulators/logic analyzers for application development. See Figures 115 and 116.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z189 MISCELLANEOUS CONTROL AND INTERFACE REGISTERS (Continued)

I/O and Memory Transactions

Z80189/Z8L189

Z80189 Data Bus (DDOUT=0)

Z80189 Data Bus (DDOUT=1)

I/O Write

to On-Chip

Peripherals

Out

I/O Read

from On-Chip

Peripherals

Out

Interrupt Acknowledge Transaction

Z80189 Data Bus (DDOUT=0)

Z80189 Data Bus (DDOUT=1)

Intack for

On-Chip

Peripheral

Out

Intack for

Off-Chip

Peripheral

I/O Write

to Off-Chip

Peripherals

Out

I/O Read

from Off-Chip

Peripherals

Write to

Memory

Out

Write from

Memory Refresh

Z80189

Idle Mode

Figure 116. Data Bus Direction (Z180 Bus Master)

The word “Out” means that the Z189 data bus direction is in output mode, “In” means input mode, and “Z” means High impedance. D

stands for Data Direction out and

DOUT

is the status of the D4 bit in the System Configuration Register.

Bit 3 Disable ROMs

If this bit is a one it disables the /ROMCS pin. If it is a zero addresses below the ROM boundary set by the ROMBR register will cause the /ROMCS pin to go low.

Bit 2 Borrow

For Bit 2 of the System Configuration Register when the bit is set to 0, the HINTR1/T bit is set to 1, the HINTR1/T

is multiplexed to T

OUT

bit is multiplexed to HINTR1.

OUT

. When this

This bit is set to 1 upon reset.

Bit 1 MIMIC/Port A

When this bit is set, MIMIC is multiplexed over Port A. This is enabled on power-up.

Bit 0 Reserved

Note: MIMIC access is disabled until the first system configuration register write after Power-up or reset. This mechanism prevents accidental bus counter from if /HDCS/HC1 pin is pulled Low. To avoid accidental contention when /HCS/HC1 is pulled low, it is advisable that the COM Decode Register is written first prior to when the system configuration register is initialized.

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z189 MISCELLANEOUS CONTROL AND INTERFACE REGISTERS (Continued)

I/O and Memory Transactions

Z80189/Z8L189

Z80189 Data Bus (DDOUT=0)

Z80189 Data Bus (DDOUT=1)

I/O Write

to On-Chip

Peripherals

I/O Read

from On-Chip

Peripherals

Out

Interrupt Acknowledge Transaction

Z80189 Data Bus (DDOUT=0)

Z80189 Data Bus (DDOUT=1)

Intack for

On-Chip

Peripheral

Out

Figure 117. Data Bus Direction (Z80180 is Not Bus Master)

Intack for

Off-Chip

Peripheral

I/O Write to Off-Chip Peripherals

I/O Read

from Off-Chip

Peripherals

Write to

Memory

Write from

Memory Refresh

Z80189

Idle Mode

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RAMCS/ROMCS

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

To assist with decoding of ROM and RAM blocks of memory, three more registers and two pins have been added to the Z80189. The two pins are /ROMCS and /RAMCS. The three registers are the ROMBR, RAMLBR and RAMUBR.

RAMUBR, RAMLBR RAM Upper Boundary, RAM Lower Range Boundary Range

These two registers specify the address range for the /RAMCS signal. When accessed memory addresses are less than or equal to the value programmed in the RAMUBR and greater than or equal to the value programmed in the RAMLBR, /RAMCS is asserted. In the case that these registers are programmed to overlap, /ROMCS takes priority over /RAMCS (/ROMCS is asserted and /RAMCS is inactive).

765 43210

11111111

A19-A12 RAMLBR

Figure 118. RAMUBR

(Z180 MPU Address XXE6H)

765 43210

11111111

A19-A12 RAMUBR

Chip Select signals are going active for the address range: ROMCS: (ROMBR) >= A19-A12 >= 0 /RAMCS: (RAMUBR) >= A19-A12 >= (RAMLBR)

These registers are set to “FFH” at power-on reset, and the boundary addresses of ROM and RAM are as follows:

ROM lower boundary address

(fixed) = 00000H

ROM upper boundary address

(ROMBR register) = 0FFFFFH

RAM lower boundary address

(RAMLBR register) = 0FFFFFH

RAM upper boundary address

(RAMUBR register) = 0FFFFFH

Since /ROMCS takes priority over /RAMCS, the latter will never be asserted until the value in the ROMBR and RAMLBR registers are re-initialized to lower values.

ROMBR ROM Address Boundary Register

This register specifies the address range for the /ROMCS signal. When accessed memory addresses are less than or equal to the value programmed in this register, the /ROMCS signal is asserted.

This signal can be forced to a "1" (inactive state) by setting Bit 3 in the System Configuration Register, to allow the user to overlay the RAM area over the ROM area.

Figure 119. RAMLBR

(Z180 Address XXE7H)

765 43210

11111111

A19-A12 ROMBR

Figure 120. ROMBR

(Z180 Address xxE8H)

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PRELIMINARY

Z80189 ROM/RAM WAIT STATE GENERATOR

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

A separate Wait State Generator is provided for access memory using /ROMCS and /RAMCS. A single eight bit register is added to enable/disable this feature as well as provide two 3-bit fields that provides a 1-8 waits for each chip select.

Bit 7 /RAMCS Wait State Generator Enable.

Disable on power-up or reset.

Bit 6-4 /RAMCS Wait States 1-8.

8 wait states on power-up or reset.

Bit 3 /ROMCS Wait State Generator Enable.

Disable on power-up or reset.

Bit 2-0 /ROMCS Wait States 1-8.

8 wait states on power-up or reset.

If Wait State is disabled or RAMCS and ROMCS is not asserted, the memory access is default to Wait State programmed in the DCNTL register of Z180 DMAs. Note that the wait states inserted by this register and DCNTL do not add. The actual number of wait states inserted is the greater of the two.

765 43210

/ROMCS Wait States 1 - 8

/ROMCS Wait State Generator Enable

/RAMCS Wait States 1 - 8

/RAMCS Wait State Generator Enable

Figure 121. WSG Chip Select Register

(Z180 MPU Read/Write, Address XXD8H)

Note: That the wait states inserted by this register and DCNTL do not add. The actual number of wait states inserted is the greater of the two.

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PRELIMINARY

INTERRUPT EDGE/PIN MUX REGISTERS

765 43210

00001100

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Halt Recovery Select 1 = 16 Cycle Delay on Halt Recovery 0 = No Wait Delay on Halt Recovery

Low Noise Select 1 = Select Low Noise for Z189 (not Z180) 0 = Select Normal Drive for Z189 Pins

IEO, /IOCS1 Select 1 = Select /IOCS1 Function 0 = Select IEO Function

/MREQ, /HRD,PC2, /MWR Select 1 Select /MRD, /MWR 0 Select /MREQ, PC2

/INT1 Mode Select 0X = Normal Level Detect 10 = Falling (Neg) Edge Det 11 = Rising (Pos) Edge Det

Figure 122. Interrupt Edge/Pin Mux Register

(Z180 MPU Address XXDFH)

Bits 7-6 control the interrupt capture logic for the external /INT2 PIN. When programmed as ‘0X’, the /INT2 pin performs as the normal level detecting interrupt pin. When programmed as ‘10’, the negative edge detection is enabled. Any falling edge will latch an active low on the internal /INT2 of the Z180. This interrupt must be cleared by writing a ‘1’ to bit 7 of the Port C Data Register. Programming these control bits to ‘11’ will enable rising edge interrupts to be latched. The latch is cleared in the same fashion as the falling edge. Interrupt Capture logic is not available in EV mode 1 (emulation adapter mode).

Bits 5-4 control the interrupt capture logic for the external /INT1 PIN. When programmed as ‘0X’, the /INT1 pin performs as the normal level detecting interrupt pin. When programmed as ‘10’, the negative edge detection is enabled. Any falling edge will latch an active low on the internal /INT1 of the Z180. This interrupt must be cleared by writing a ‘1’ to bit 6 of the Port C Data Register. Programming these control bits to ‘11’ will enable rising edge interrupts to be latched. The latch is cleared in the same fashion as the falling edge. Interrupt Capture Logic is not available in EV mode 1 (emulator adaption mode).

/INT2 Mode Select 0X = Normal Level Detect 10 = Falling (Neg) Edge Det 11 = Rising (Pos) Edge Det

Bit 3 Programming this bit to 1 selects the /MRD and the /MWR outputs. When this bit is set, /MREQ will be removed for the qualification of both /RAMCS and /ROMCS. By programming this bit to 0, the /MREQ Z180 and PC2 outputs are enabled. This bit is 0 upon reset.

Bit 2 selects the /IOCS1 function which is the default for power up and /RESET conditions. By programming this bit to ‘0’, the IEO function is enabled for this multiplexed pin.

Bit 1 selects the low noise or normal drive feature for the Z189 pins. The default at power up is normal drive for Z189 pins. By programming this bit to ‘1’, low noise for the Z189 pins is chosen (not the Z180 pins). Programming this bit to ‘0’ selects normal drive for the Z189 pins. Z189 pins include: all MIMIC output pins, ROM/RAM chip selects, bit I/O, IOCS1, IOCS2, and PC DMA Mailbox outputs.

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PRELIMINARY

INTERRUPT EDGE/PIN MUX REGISTERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Bit 0 A ‘1’ selects 16 cycle wait delay on recovery from Halt

if bit 5 of the Z80189 Enhancements Register Z180 MPU Address D9H is set to zero. A ‘0’ selects no wait delay on Halt recovery. The definition of Halt recovery is as follows. If this mode is selected the following pins assume the following states during halt and during the recovery, whether it is in Halt, SLP, IDLE or STBY Modes:

Address = Z Data Bus = Z /RD = Z /WR = Z /MREQ = Z /M1 = 1 ST = 1 /IORQ = 1 /BUSACK = 1 (1) /RFSH = 1 (2) /IOCS1 = Z (3) /IOCS2 = Z HDRQ0 = Z (3) HDRQ1 = Z (3)

Note 1. This assumes that BUSREQ is not activated during

the halt.

Note 2. This assumes that the refresh is not enabled. This

would not be a logical case since the address bus is tri-stated during the Halt mode.

Note 3. This is only true if the function is enabled.

The Halt recovery mode is implemented by applying wait states to the next cpu operation following the exit from halt. All signals listed above are forced to their specified state (unless otherwise noted) during halt and also during the recovery state. Sixteen cycles after the halt pin goes high the signals are released to their normal state. Then eight wait states are inserted to allow proper access to accommodate slow memories.

Z80189 ENHANCEMENTS REGISTER (Z180 MPU ADDRESS D9H)

Bit 7 Forced /ROMCS Memory Boundary. When this bit is

set to 1, it will force the /ROMCS boundary. A19 will be connected directly to /ROMCS. /ROMCS will then be asserted from 00000H-7FFFFH. When this bit is cleared, /ROMCS will be accessed under the programmed address decoder range. This bit is 0 upon rest.

Note: In this mode, chip select assertion is NOT dependent on /MREQ assertion. During Sleep, /ROMCS will be forced inactive high.

Bit 6 Forced /RAMCS Memory Boundary. When this bit is set to 1, it will force the /RAMCS boundary. /A19 will be connected to /RAMCS. /RAMCS will then be asserted from 8000H-FFFFFH. When this bit is cleared, /RAMCS will be accessed under the programmed address decoder range. This bit is 0 upon reset.

Note: In this mode, chip select assertion is NOT dependent on /MREQ assertion. During sleep, /RAMCS is forced inactive.

When using the forced memory boundaries, the memory access time requirement is improved. The improved Memory access time equation is shown below:

Note: When using forced ROM boundary without forced RAM boundary, or forced RAM boundary without forced ROM boundary, contention is possible (both /ROMCS & /RAMCS active). Care should be taken when programming memory boundaries such that there is no overlap.

Bit 5 Force Z180 Halt Mode (Write/Read). MPU Signals are the same as Z180 during HALT modes. This allows bus acknowledge cycles during Z189 HALT modes.

Bit 1:4 Reserved

Bit 0 PHI Output Disable. When this bit is set, the PHI

output is not driven by the system clock. The PHI output will be forced high in this mode. On production boards that do not use the PHI output, this feature can be used to reduce EMI. When this bit is reset, the system clock is output to PHI pin. This bit is reset by default. This feature is not usable in EV mode 1 (emulation adapter) or EV mode 2 (emulation probe).

ACC Time < (2 + WS) *clkperiod-Tad-Tdrs

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PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189 ENHANCEMENTS REGISTER I(Z180 MPU ADDRESS D9H) (Continued)

765 43210

000XXXX0

PHI Output Disable Reserved

Force Z180 Halt Mode Forced /RAMCS

Memory Boundary Forced /ROMCS

Memory Boundary

Figure 123. Z80189 Enhancements Register

(Z180 MPU Address 09H)

Z80189/Z8L189

PARALLEL PORTS REGISTERS

The Z80189 has three eight bit bidirectional ports. Each bit is individually programmable for input or output. The ports consist of two registers: the Port Direction Control Register and the Port Data Register. The port and direction register can be accessed in any page of I/O space since only the lowest eight address lines are decoded. Bits PC7 and PC6 are input only bits and have the special function of reading the external value of the /INT2 AND /INT1 pins. Writing ‘1’ to these bits will clear the edge detect interrupt logic when operating /INT2 and/or /INT1 in edge detect mode.

When Port B and Port C bits 5-0 are deselected in the System Configuration Register, the Data and Data Direction Registers are still available as read/write scratch registers. If a port is deselected and if the DDR bit is a ‘0’, then the written value to that bit will be latched; and this value can be read back. If a port is deselected and if the DDR bit is a ‘1’, then you could read only the external pin value; any write to that bit is latched but can be read back only with DDR=0.

765 43210

11111111

PA Data Direction Register 0 = Output 1 = Input

Figure 124. PA Data Direction Register

(Z180 MPU Address XXEDH)

The data direction register determines which are inputs and outputs in the PA Data Register. When a bit is set to a one, the corresponding bit in the PA Data Register is an input. If the bit is zero, then the corresponding bit is an output.

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PRELIMINARY

PARALLEL PORTS REGISTERS (Continued)

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

765 43210 XXXXXXXX

PA Data Register

Figure 125. PA Data Register

(Z180 MPU Address XXEEH)

When the Z180 MPU writes to the PA Data Register, the data is stored in the internal buffer. Any bits that are output are then sent on to the output buffers.

When the Z180 MPU reads the PA Data Register, the data on the external pins is returned.

765 43210

11111111

PB Data Direction Register 0 = Output 1 = Input

Figure 126. PB Data Direction Register

(Z180 MPU Address XXE4H)

765 43210

XX111111

PB Data Direction Register 0 = Output 1 = Input

Reserved

Figure 128. PC Data Direction Register

(Z180 MPU Address XXDDH)

The data direction register determines which are inputs and outputs in the PB Data Register. When a bit is set to a one, the corresponding bit in the PB Data Register is an input. If the bit is zero, then the corresponding bit is an output.

765 43210 XXXXXXXX

/INT2, /INT1 Read Ext Data Write B7=1 Clears /INT2 Edge Write B6=1 Clears /INT1 Edge

PC Data Register

765 43210 XXXXXXXX

PB Data Register

Figure 127. PB Data Register

(Z180 MPU Address XXE5H)

When the Z180 MPU writes to the PB Data Register, the data is stored in the internal buffer. Any bits that are output are then sent on to the output buffers.

When the Z180 MPU reads the PB Data Register, the data on the external pins is returned.

Figure 129. PC, Port C, Data Register

(Z180 MPU Address XXDEH)

When the Z180 MPU writes to the PC Data Register, the data is stored in the internal buffer. Any bits that are output are then sent on to the output buffers.

When the Z180 MPU reads the PC Data Register, the data on the external pins is returned.

Bits 7 and 6 serve the special function of reading the value of the external /INT2 and /INT1 lines. When operating either /INT2 or /INT1 in edge detection mode, the edge detect latch is reset by writing a '1' to bit 7 or 6 respectively. Writing a '0' has no effect. These latches should be reset

at the end of an /INT1 or /INT2 interrupts service routine when using edge-triggered interrupt routine.

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EMULATION MODES

PRELIMINARY

GENERAL-PURPOSE EMBEDDED CONTROLLERS

Z80189/Z8L189

Z80189 provides four modes of operation. The modes are selected by the EV1 and EV2 pins. These four modes allow for system development while the MIMIC is disabled, and T

is active.

OUT

EV2 EV1

Mode 0 0 0 Normal Mode, on-chip Z180

bus master Mode 1 0 1 Emulation Adapter Mode Mode 2 1 0 Emulator Probe Mode Mode 3 1 1 Reserved Mode 0 Description

Mode 0 Normal Mode

This is the normal operating mode for the Z80189.

Mode 1 Description

The Emulation Adapter Mode enables system development for the Z189 with a readily available Z180 emulator. The Emulator provides the Z180 MPU and Z180 peripheral functions to the target system, with their signals passing through the emulation adapter. In Emulation Adapter Mode, the Z189’s, Z180 MPU and Z180 peripheral signals are tristated or physically disconnected. The Z189 continues to provide its BRG, COM Port Decoder, MIMIC and Port functions and signals to the target system. The Mode 1 effects on the Z189 are:

Mode 0 Mode 1

Signal Normal Emulation Adapter

PHI Output Input /M1 Output Input /MREQ,/MRD Output Input /MWR Output Input /IORQ Output Input /RD Output Input /WR Output Input /RFSH Output Input /HALT Output Input ST Output Input /BUSACK Output Input /WAIT Input Output A19,A18 Output Input A17-A0 Output Input D7-D0 Input/Output Input/Output TXA0 Output Tri-state /RTS0 Output Tri-state TXA1 Output Tri-state /INT0 Input Output, Open-Drain

Mode 2 Description

In the Emulator Probe Mode, all the Z189 output signals are tri-stated. This scheme allows a Z189 emulator probe to grab onto the Z189 package leads on the target system.

Mode 3 Description

Reserved for Test Mode.

Note also that in Mode 1 and 3, the emulator must provide /MREQ on the (/MREQ) Z80189 pin.

100

DS971890301

Datasheet Z8018933ASC, Z8018933FSC, Z8L18920ASC, Z8L18920FSC Datasheet (ZILOG)

Specifications and Main Features

Frequently Asked Questions

User Manual

PIN DESCRIPTION

ABSOLUTE MAXIMUM RATINGS

DC CHARACTERISTICS

AC CHARACTERISTICS