Philips 8xc54, 51fx, 51rx DATASHEETS

INTEGRATED CIRCUITS

8XC54/58 8XC51FA/FB/FC/80C51FA 8XC51RA+/RB+/RC+/RD+/80C51RA +

80C51 8-bit microcontroller family

8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power , high speed (33 MHz)

Product specification

Replaces datasheet 8XC52/54/58/80C32 8XC51FA/FB/FC/80C51FA 8XC51RA+/RB+/RC+/RD+/80C51RA + of 1999 Apr 01

2000 Aug 07

 

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

DESCRIPTION

Three different Single-Chip 8-Bit Microcontroller families are presented in this datasheet:

•8XC54/8XC58

•80C51FA/8XC51FA/8XC51FB/8XC51FC

•80C51RA+/8XC51RA+/8XC51RB+/8XC51RC+/8XC51RD+

For applications requiring 4K ROM/EPROM, see the 8XC51/80C31 8-bit CMOS (low voltage, low power, and high speed) microcontroller families datasheet.

All the families are Single-Chip 8-Bit Microcontrollers manufactured in advanced CMOS process and are derivatives of the 80C51 microcontroller family. All the devices have the same instruction set as the 80C51.

These devices provide architectural enhancements that make them applicable in a variety of applications for general control systems.

ROM/EPROM Memory Size

(X by 8)

80C31/8XC51

0K/4K 128 No No

8XC54/58

0K/8K/16K/32K 256 No No

80C51FA/8XC51FA/FB/FC

0K/8K/16K/32K 256 Yes No

80C51RA+/8XC51RA+/RB+/RC+

0K/8K/16K/32K 512 Yes Yes

8XC51RD+

64K 1024 Yes Yes

RAM Size

(X by 8)

Programmable

Timer Counter

(PCA)

Hardware

Watch Dog

Timer

FEA TURES

•80C51 Central Processing Unit

•Speed up to 33 MHz

•Full static operation

•Operating voltage range: 2.7 V to 5.5 V @ 16 MHz

•Security bits:

•Encryption array – 64 bytes

•RAM expandable to 64K bytes

•4 level priority interrupt

•6 or7 interrupt sources, depending on device

•Four 8-bit I/O ports

•Full-duplex enhanced UART

•Power control modes

•Programmable clock out

•Second DPTR register

•Asynchronous port reset

•Low EMI (inhibit ALE)

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

– ROM – 2 bits – OTP–EPROM – 3 bits

– Framing error detection – Automatic address recognition

– Clock can be stopped and resumed – Idle mode – Power down mode

The ROMless devices, 80C51FA, and 80C51RA+ can address up to 64K of external memory . All the devices have four 8-bit I/O ports, three 16-bit timer/event counters, a multi-source, four-priority-level, nested interrupt structure, an enhanced UART and on-chip oscillator and timing circuits. For systems that require extra memory capability up to 64k bytes, each can be expanded using standard TTL-compatible memories and logic.

Its added features make it an even more powerful microcontroller for applications that require pulse width modulation, high-speed I/O and up/down counting capabilities such as motor control. It also has a more versatile serial channel that facilitates multiprocessor communications.

2000 Aug 07 853-2068 24292

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

BLOCK DIAGRAM

P0.0–P0.7 P2.0–P2.7

PORT 0

DRIVERS

RAM ADDR REGISTER

RAM

ACC

TMP2

PORT 0

LATCH

TMP1

PORT 2

DRIVERS

PORT 2

LATCH

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

ROM/EPROM

STACK

POINTER

PROGRAM

ADDRESS

PSEN

ALE/PROG

EAV

RST

TIMING

AND

CONTROL

OSCILLATOR

XTAL1 XTAL2

INSTRUCTION

PSW

PORT 1

LATCH

PORT 1

DRIVERS

P1.0–P1.7

ALU

SFRs

TIMERS

P.C.A. (FA & RA+ only)

PORT 3

LATCH

PORT 3

DRIVERS

P3.0–P3.7

BUFFER

INCRE-

MENTER

8 16

PROGRAM COUNTER

DPTR’S

MULTIPLE

SU00831B

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

LOGIC SYMBOL

XTAL1

ADDRESS AND

DATA BUS

T2 T2EX

PORT 1PORT 2

ADDRESS BUS

SU00830

EA/V

PSEN

ALE/PROG RxD TxD

INT0 INT1

T0 T1

SECONDARY FUNCTIONS

XTAL2

RST

PORT 0

PORT 3

PIN CONFIGURA TIONS

DUAL IN-LINE PACKAGE PIN FUNCTIONS

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

PLASTIC LEADED CHIP CARRIER PIN FUNCTIONS

6140

Pin Function

1 NIC* 2 P1.0/T2 3 P1.1/T2EX 4 P1.2/ECI 5 P1.3/CEX0 6 P1.4/CEX1 7 P1.5/CEX2 8 P1.6/CEX3

9 P1.7/CEX4 10 RST 11 P3.0/RxD 12 NIC* 13 P3.1/TxD 14 P3.2/INT0 15 P3.3/INT1

* NO INTERNAL CONNECTION

LCC

18 28

Pin Function

16 P3.4/T0 17 P3.5/T1 18 P3.6/WR 19 P3.7/RD 20 XTAL2 21 XTAL1 22 V

23 NIC* 24 P2.0/A8 25 P2.1/A9 26 P2.2/A10 27 P2.3/A11 28 P2.4/A12 29 P2.5/A13 30 P2.6/A14

Pin Function

31 P2.7/A15 32 PSEN 33 ALE/PROG 34 NIC* 35 EA/V 36 P0.7/AD7 37 P0.6/AD6 38 P0.5/AD5 39 P0.4/AD4 40 P0.3/AD3 41 P0.2/AD2 42 P0.1/AD1 43 P0.0/AD0 44 V

SU00023

T2/P1.0

T2EX/P1.1

ECI/P1.2 CEX0/P1.3 CEX1/P1.4 CEX2/P1.5 CEX3/P1.6 CEX4/P1.7

RST RxD/P3.0 TxD/P3.1

/P3.2

INT0 INT1

/P3.3 T0/P3.4 T1/P3.5

/P3.6

/P3.7

XTAL2 XTAL1

1 2 3 4 5 6 7 8 9

DUAL

IN-LINE

PACKAGE

11 12 13 14 15 16 17 18 19 20

P0.0/AD0

39 38

P0.1/AD1

P0.2/AD2

P0.3/AD3

P0.4/AD4

P0.5/AD5

P0.6/AD6

P0.7/AD7 EA/V

31 30

ALE/PROG

PSEN

P2.7/A15

P2.6/A14

P2.5/A13

P2.4/A12

P2.3/A11

P2.2/A10

P2.1/A9

P2.0/A8

SU00021

PLASTIC QUAD FLAT PACK PIN FUNCTIONS

44 34

PQFP

12 22

Pin Function

1 P1.5/CEX2 2 P1.6/CEX3 3 P1.7/CEX4 4 RST 5 P3.0/RxD 6 NIC* 7 P3.1/TxD 8 P3.2/INT0

9 P3.3/INT1 10 P3.4/T0 11 P3.5/T1 12 P3.6/WR 13 P3.7/RD 14 XTAL2 15 XTAL1

* NO INTERNAL CONNECTION

Pin Function

16 V

17 NIC* 18 P2.0/A8 19 P2.1/A9 20 P2.2/A10 21 P2.3/A11 22 P2.4/A12 23 P2.5/A13 24 P2.6/A14 25 P2.7/A15 26 PSEN 27 ALE/PROG 28 NIC* 29 EA

30 P0.7/AD7

Pin Function

31 P0.6/AD6 32 P0.5/AD5 33 P0.4/AD4 34 P0.3/AD3 35 P0.2/AD2 36 P0.1/AD1 37 P0.0/AD0 38 V

39 NIC* 40 P1.0/T2 41 P1.1/T2EX 42 P1.2/ECI 43 P1.3/CEX0 44 P1.4/CEX1

SU00024

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC54/58

PIN DESCRIPTIONS

PIN NUMBER

MNEMONIC DIP LCC QFP TYPE NAME AND FUNCTION

P0.0–0.7 39–32 43–36 37–30 I/O Port 0: Port 0 is an open-drain, bidirectional I/O port. Port 0 pins that have 1s written to

P1.0–P1.7 1–8 2–9 40–44,

P2.0–P2.7 21–28 24–31 18–25 I/O Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2 pins that have 1s

P3.0–P3.7 10–17 11,

RST 9 10 4 I Reset: A high on this pin for two machine cycles while the oscillator is running, resets the

ALE/PROG 30 33 27 O Address Latch Enable/Program Pulse: Output pulse for latching the low byte of the

20 22 16 I Ground: 0 V reference. 40 44 38 I Power Supply: This is the power supply voltage for normal, idle, and power-down operation.

them float and can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external program and data memory. In this application, it uses strong internal pull-ups when emitting 1s. Port 0 also outputs the code bytes during program verification and received code bytes during EPROM programming. External pull-ups are required during program verification.

I/O Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. Port 1 pins that have 1s

1–3

1 2 40 I/O T2 (P1.0): Timer/Counter 2 external count input/Clockout (see Programmable Clock-Out) 2 3 41 I T2EX (P1.1): Timer/Counter 2 Reload/Capture/Direction Control 3 4 42 I ECI (P1.2): External Clock Input to the PCA 4 5 43 I/O CEX0 (P1.3): Capture/Compare External I/O for PCA module 0 5 6 44 I/O CEX1 (P1.4): Capture/Compare External I/O for PCA module 1 6 7 1 I/O CEX2 (P1.5): Capture/Compare External I/O for PCA module 2 7 8 2 I/O CEX3 (P1.6): Capture/Compare External I/O for PCA module 3 8 9 3 I/O CEX4 (P1.7): Capture/Compare External I/O for PCA module 4

13–195,7–13

10 11 5 I RxD (P3.0): Serial input port 11 13 7 O TxD (P3.1): Serial output port 12 14 8 I INT0 (P3.2): External interrupt 13 15 9 I INT1 (P3.3): External interrupt 14 16 10 I T0 (P3.4): Timer 0 external input 15 17 11 I T1 (P3.5): Timer 1 external input 16 18 12 O WR (P3.6): External data memory write strobe 17 19 13 O RD (P3.7): External data memory read strobe

written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 1 pins that are externally pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: I during program memory verification.

Alternate functions for 8XC51FX and 8XC51RX+ Port 1 include:

written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 2 pins that are externally being pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: I

during fetches from external program memory and during accesses to external data memory

that use 16-bit addresses (MOVX @DPTR). In this application, it uses strong internal pull-ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOV @Ri), port 2 emits the contents of the P2 special function register. Some Port 2 pins receive the high order address bits during EPROM programming and verification.

I/O Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins that have 1s

written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 3 pins that are externally being pulled low will source current because of the pull-ups. (See DC Electrical Characteristics: I family, as listed below:

device. An internal diffused resistor to V capacitor to V

address during an access to external memory. In normal operation, ALE is emitted at a constant rate of 1/6 the oscillator frequency, and can be used for external timing or clocking. Note that one ALE pulse is skipped during each access to external data memory. This pin is also the program pulse input (PROG setting SFR auxiliary.0. With this bit set, ALE will be active only during a MOVX instruction.

). Port 1 also receives the low-order address byte

). Port 2 emits the high-order address byte

). Port 3 also serves the special features of the 80C51

permits a power-on reset using only an external

) during EPROM programming. ALE can be disabled by

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC54/58

PIN DESCRIPTIONS (Continued)

PIN NUMBER

MNEMONIC DIP LCC QFP TYPE NAME AND FUNCTION

PSEN 29 32 26 O Program Store Enable: The read strobe to external program memory. When executing

code from the external program memory, PSEN except that two PSEN PSEN

is not activated during fetches from internal program memory.

EA/V

XTAL1 19 21 15 I Crystal 1: Input to the inverting oscillator amplifier and input to the internal clock generator

XTAL2 18 20 14 O Crystal 2: Output from the inverting oscillator amplifier.

NOTE:

To avoid “latch-up” effect at power-on, the voltage on any pin at any time must not be higher than V

31 35 29 I External Access Enable/Programming Supply Voltage: EA must be externally held low

to enable the device to fetch code from external program memory locations starting with 0000H. If EA program counter contains an address greater than 8k Devices (IFFFH), 16k Devices (3FFFH) or 32k Devices (7FFFH). Since the RD+ has 64k Internal Memory, the RD+ will execute only from internal memory when EA programming supply voltage (V programmed, EA

circuits.

is held high, the device executes from internal program memory unless the

activations are skipped during each access to external data memory.

) during EPROM programming. If security bit 1 is

will be internally latched on Reset.

is activated twice each machine cycle,

is held high. This pin also receives the 12.75 V

+ 0.5 V or VSS – 0.5 V, respectively.

2000 Aug 07

Philips Semiconductors Product specification

0 to +70, Plastic Dual In-line Package

0 to 16

SOT129-1

0 to +70, Plastic Leaded Chip Carrier

0 to 16

SOT187-2

0 to +70, Plastic Quad Flat Pack

0 to 16

SOT307-2

Plastic Dual In-line Package

0 to 16

SOT129-1

Plastic Leaded Chip Carrier

0 to 16

SOT187-2

Plastic Quad Flat Pack

0 to 16

SOT307-2

0 to +70, Plastic Leaded Chip Carrier

5 V

0 to 33

SOT187-2

0 to +70, Plastic Dual In-line Package

5 V

0 to 33

SOT129-1

0 to +70, Plastic Quad Flat Pack

5 V

0 to 33

SOT307-2

Plastic Leaded Chip Carrier

5 V

0 to 33

SOT187-2

Plastic Dual In-line Package

5 V

0 to 33

SOT129-1

Plastic Quad Flat Pack

5 V

0 to 33

SOT307-2

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33 MHz)

8XC54/58 ORDERING INFORMATION

MEMORY SIZE

16K × 8

ROM P80C54SBPN P80C58SBPN OTP P87C54SBPN P87C58SBPN ROM P80C54SBAA P80C58SBAA OTP P87C54SBAA P87C58SBAA ROM P80C54SBBB P80C58SBBB OTP P87C54SBBB P87C58SBBB ROM P80C54SFPN P80C58SFPN OTP P87C54SFPN P87C58SFPN ROM P80C54SFAA P80C58SFAA OTP P87C54SFAA P87C58SFAA ROM P80C54SFBB P80C58SFBB OTP P87C54SFBB P87C58SFBB ROM P80C54UBAA P80C58UBAA OTP P87C54UBAA P87C58UBAA ROM P80C54UBPN P80C58UBPN OTP P87C54UBPN P87C58UBPN ROM P80C54UBBB P80C58UBBB OTP P87C54UBBB P87C58UBBB ROM P80C54UFAA P80C58UFAA OTP P87C54UFAA P87C58UFAA ROM P80C54UFPN P80C58UFPN OTP P87C54UFPN P87C58UFPN ROM P80C54UFBB P80C58UFBB OTP P87C54UFBB P87C58UFBB

Note: For Multi Time Programmable devices, See P89C51RX+ Flash datasheet.

MEMORY SIZE

32K × 8

TEMPERATURE RANGE °C

AND PACKAGE

–40 to +85,

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

VOLTAGE

RANGE

2.7 V to

5.5 V

2.7 V to

5.5 V

2.7 V to

5.5 V

2.7 V to

5.5 V

2.7 V to

5.5 V

2.7 V to

5.5 V

FREQ.

(MHz)

8XC54/58

DWG.

2000 Aug 07

8XC51FA/FB/FC AND 80C51FA ORDERING INFORMATION

P80C51FA–4N

0 to +70, 40-Pin Plastic Dual In-line Pkg

2.7V to 5.5V

0 to 16

SOT129-1

P80C51FA–4A

0 to +70, 44-Pin Plastic Leaded Chip Carrier

2.7V to 5.5V

0 to 16

SOT187-2

P80C51FA–4B

0 to +70, 44-Pin Plastic Quad Flat Pack

2.7V to 5.5V

0 to 16

SOT307-2

P80C51FA–5N

Pin Plastic Dual In-line Pkg

2.7V to 5.5V

0 to 16

SOT129-1

P80C51FA–5A

Pin Plastic Leaded Chip Carrier

2.7V to 5.5V

0 to 16

SOT187-2

P80C51FA–5B

Pin Plastic Quad Flat Pack

2.7V to 5.5V

0 to 16

SOT307-2

P80C51FA–IN

0 to +70, 40-Pin Plastic Dual In-line Pkg

0 to 33

SOT129-1

P80C51FA–IA

0 to +70, 44-Pin Plastic Leaded Chip Carrier

0 to 33

SOT187-2

P80C51FA–IB

0 to +70, 44-Pin Plastic Quad Flat Pack

0 to 33

SOT307-2

P80C51FA–JN

Pin Plastic Dual In-line Pkg

0 to 33

SOT129-1

P80C51FA–JA

Pin Plastic Leaded Chip Carrier

0 to 33

SOT187-2

P80C51FA–JB

Pin Plastic Quad Flat Pack

0 to 33

SOT307-2

MEMORY SIZE

8K × 8

ROM P83C51FA–4N P83C51FB–4N P83C51FC–4N

OTP P87C51FA–4N P87C51FB–4N P87C51FC–4N

ROM P83C51FA–4A P83C51FB–4A P83C51FC–4A

OTP P87C51FA–4A P87C51FB–4A P87C51FC–4A

ROM P83C51FA–4B P83C51FB–4B P83C51FC–4B

OTP P87C51FA–4B P87C51FB–4B P87C51FC–4B

ROM P83C51FA–5N P83C51FB–5N P83C51FC–5N

OTP P87C51FA–5N P87C51FB–5N P87C51FC–5N

ROM P83C51FA–5A P83C51FB–5A P83C51FC–5A

OTP P87C51FA–5A P87C51FB–5A P87C51FC–5A

ROM P83C51FA–5B P83C51FB–5B P83C51FC–5B

OTP P87C51FA–5B P87C51FB–5B P87C51FC–5B

ROM P83C51FA–IN P83C51FB–IN P83C51FC–IN

OTP P87C51FA–IN P87C51FB–IN P87C51FC–IN

ROM P83C51FA–IA P83C51FB–IA P83C51FC–IA

OTP P87C51FA–IA P87C51FB–IA P87C51FC–IA

ROM P83C51FA–IB P83C51FB–IB P83C51FC–IB

82000 Aug 07

OTP P87C51FA–IB P87C51FB–IB P87C51FC–IB

ROM P83C51FA–JN P83C51FB–JN P83C51FC–JN

OTP P87C51FA–JN P87C51FB–JN P87C51FC–JN

ROM P83C51FA–JA P83C51FB–JA P83C51FC–JA

OTP P87C51FA–JA P87C51FB–JA P87C51FC–JA

ROM P83C51FA–JB P83C51FB–JB P83C51FC–JB

OTP P87C51FA–JB P87C51FB–JB P87C51FC–JB

Note: For Multi Time Programmable devices, See P89C51RX+ Flash datasheet.

MEMORY SIZE

16K × 8

MEMORY SIZE

32K × 8

ROMless

TEMPERATURE RANGE °C

–40 to +85, 40-

–40 to +85, 44-

–40 to +85, 40-

–40 to +85, 44-

AND PACKAGE

low power, high speed (33MHz)

8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V),

VOLTAGE

RANGE

FREQ.

(MHz)

DWG.

Philips Semiconductors Product specification

80C51 8-bit microcontroller family

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC51FA/FB/FC/80C51FA

8XC54/58

87C51RA+/RB+/RC+/RD+ AND 80C51RA+ ORDERING INFORMATION

P80C51RA+4N

2.7V to 5.5V

0 to 16

SOT129-1

P80C51RA+4A

2.7V to 5.5V

0 to 16

SOT187-2

P80C51RA+4B

2.7V to 5.5V

0 to 16

SOT307-2

P80C51RA+5N

2.7V to 5.5V

0 to 16

SOT129-1

P80C51RA+5A

2.7V to 5.5V

0 to 16

SOT187-2

P80C51RA+5B

2.7V to 5.5V

0 to 16

SOT307-2

P80C51RA+IN

0 to 33

SOT129-1

P80C51RA+IA

0 to 33

SOT187-2

P80C51RA+IB

0 to 33

SOT307-2

P80C51RA+JN

0 to 33

SOT129-1

P80C51RA+JA

0 to 33

SOT187-2

P80C51RA+JB

0 to 33

SOT307-2

MEMORY SIZE

8K × 8

ROM P83C51RA+4N P83C51RB+4N P83C51RC+4N P83C51RD+4N

OTP P87C51RA+4N P87C51RB+4N P87C51RC+4N P87C51RD+4N

ROM P83C51RA+4A P83C51RB+4A P83C51RC+4A P83C51RD+4A

OTP P87C51RA+4A P87C51RB+4A P87C51RC+4A P87C51RD+4A

ROM P83C51RA+4B P83C51RB+4B P83C51RC+4B P83C51RD+4B

OTP P87C51RA+4B P87C51RB+4B P87C51RC+4B P87C51RD+4B

ROM P83C51RA+5N P83C51RB+5N P83C51RC+5N P83C51RD+5N

OTP P87C51RA+5N P87C51RB+5N P87C51RC+5N P87C51RD+5N

ROM P83C51RA+5A P83C51RB+5A P83C51RC+5A P83C51RD+5A

OTP P87C51RA+5A P87C51RB+5A P87C51RC+5A P87C51RD+5A

ROM P83C51RA+5B P83C51RB+5B P83C51RC+5B P83C51RD+5B

OTP P87C51RA+5B P87C51RB+5B P87C51RC+5B P87C51RD+5B

ROM P83C51RA+IN P83C51RB+IN P83C51RC+IN P83C51RD+IN

92000 Aug 07

OTP P87C51RA+IN P87C51RB+IN P87C51RC+IN P87C51RD+IN

ROM P83C51RA+IA P83C51RB+IA P83C51RC+IA P83C51RD+IA

OTP P87C51RA+IA P87C51RB+IA P87C51RC+IA P87C51RD+IA

ROM P83C51RA+IB P83C51RB+IB P83C51RC+IB P83C51RD+IB

OTP P87C51RA+IB P87C51RB+IB P87C51RC+IB P87C51RD+IB

ROM P83C51RA+JN P83C51RB+JN P83C51RC+JN P83C51RD+JN

OTP P87C51RA+JN P87C51RB+JN P87C51RC+JN P87C51RD+JN

ROM P83C51RA+JA P83C51RB+JA P83C51RC+JA P83C51RD+JA

OTP P87C51RA+JA P87C51RB+JA P87C51RC+JA P87C51RD+JA

ROM P83C51RA+JB P83C51RB+JB P83C51RC+JB P83C51RD+JB

OTP P87C51RA+JB P87C51RB+JB P87C51RC+JB P87C51RD+JB

Note: For Multi Time Programmable devices, See P89C51RX+ Flash datasheet.

MEMORY SIZE

16K × 8

MEMORY SIZE

32K × 8

MEMORY SIZE

64K × 8

ROMless

TEMPERATURE RANGE °C

AND PACKAGE

0 to +70,

40-Pin Plastic Dual In-line Pkg.

0 to +70,

44-Pin Plastic Leaded Chip Carrier

0 to +70,

44-Pin Plastic Quad Flat Pack

–40 to +85,

40-Pin Plastic Dual In-line Pkg.

–40 to +85,

44-Pin Plastic Leaded Chip Carrier

–40 to +85,

44-Pin Plastic Quad Flat Pack

0 to +70,

40-Pin Plastic Dual In-line Pkg.

0 to +70,

44-Pin Plastic Leaded Chip Carrier

0 to +70,

44-Pin Plastic Quad Flat Pack

–40 to +85,

40-Pin Plastic Dual In-line Pkg.

–40 to +85,

44-Pin Plastic Leaded Chip Carrier

–40 to +85,

44-Pin Plastic Quad Flat Pack

VOLTAGE

RANGE

FREQ.

(MHz)

DWG.

low power, high speed (33MHz)

8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V),

Philips Semiconductors Product specification

80C51 8-bit microcontroller family

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC51FA/FB/FC/80C51FA

8XC54/58

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC54/58

Table 1. 8XC54/58 Special Function Registers

SYMBOL DESCRIPTION

ACC* Accumulator E0H E7 E6 E5 E4 E3 E2 E1 E0 00H AUXR# Auxiliary 8EH – – – – – – – AO xxxxxxx0B AUXR1# Auxiliary 1 A2H – – – LPEP B* B register F0H F7 F6 F5 F4 F3 F2 F1 F0 00H DPTR: Data Pointer (2 bytes)

DPH Data Pointer High 83H 00H DPL Data Pointer Low 82H 00H

IE* Interrupt Enable A8H EA – ET2 ES ET1 EX1 ET0 EX0 0x000000B

IP* Interrupt Priority B8H – – PT2 PS PT1 PX1 PT0 PX0 xx000000B

IPH# Interrupt Priority High B7H – – PT2H PSH PT1H PX1H PT0H PX0H xx000000B

P0* Port 0 80H AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0 FFH

P1* Port 1 90H – – – – – – T2EX T2 FFH

P2* Port 2 A0H AD15 AD14 AD13 AD12 AD11 AD10 AD9 AD8 FFH

P3* Port 3 B0H RD WR T1 T0 INT1 INT0 TxD RxD FFH

DIRECT

ADDRESS

BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION MSB LSB

GF3 0 – DPS xxx0xxx0B

AF AE AD AC AB AA A9 A8

BF BE BD BC BB BA B9 B8

B7 B6 B5 B4 B3 B2 B1 B0

87 86 85 84 83 82 81 80

97 96 95 94 93 92 91 90

A7 A6 A5 A4 A3 A2 A1 A0

B7 B6 B5 B4 B3 B2 B1 B0

RESET VALUE

PCON#1Power Control 87H SMOD1 SMOD0 – POF

D7 D6 D5 D4 D3 D2 D1 D0

PSW* Program Status Word D0H CY AC F0 RS1 RS0 OV – P 000000x0B

RCAP2H# Timer 2 Capture High CBH 00H RCAP2L# T imer 2 Capture Low CAH 00H

SADDR# Slave Address A9H 00H SADEN# Slave Address Mask B9H 00H

SBUF Serial Data Buffer 99H xxxxxxxxB

9F 9E 9D 9C 9B 9A 99 98 SCON* Serial Control 98H SP Stack Pointer 81H 07H

TCON* Timer Control 88H TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0 00H

T2CON* Timer 2 Control C8H TF2 EXF2 RCLK TCLK EXEN2 TR2 C/T2 CP/RL2 00H T2MOD# Timer 2 Mode Control C9H – – – – – – T2OE DCEN xxxxxx00B

TH0 Timer High 0 8CH 00H TH1 Timer High 1 8DH 00H TH2# Timer High 2 CDH 00H TL0 Timer Low 0 8AH 00H TL1 Timer Low 1 8BH 00H TL2# Timer Low 2 CCH 00H

TMOD Timer Mode 89H GATE C/T M1 M0 GATE C/T M1 M0 00H

* SFRs are bit addressable. # SFRs are modified from or added to the 80C51 SFRs. – Reserved bits.

1. Reset value depends on reset source.

2. Bit will not be affected by Reset.

3. LPEP – Low Power OTP–EPROM only operation.

SM0/FE

8F 8E 8D 8C 8B 8A 89 88

CF CE CD CC CB CA C9 C8

SM1 SM2 REN TB8 RB8 TI RI 00H

GF1 GF0 PD IDL 00xx0000B

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC54/58

T able 2. 8XC51FA/FB/FC, 8XC51RA+/RB+/RC+/RD+ Special Function Registers

SYMBOL DESCRIPTION

ACC* Accumulator E0H E7 E6 E5 E4 E3 E2 E1 E0 00H AUXR# Auxiliary 8EH – – – – – –

AUXR1# Auxiliary 1 A2H – – – LPEP3GF3 0 – DPS xxx0xxx0B B* B register F0H F7 F6 F5 F4 F3 F2 F1 F0 00H CCAP0H# Module 0 Capture High FAH xxxxxxxxB

CCAP1H# Module 1 Capture High FBH xxxxxxxxB CCAP2H# Module 2 Capture High FCH xxxxxxxxB CCAP3H# Module 3 Capture High FDH xxxxxxxxB CCAP4H# Module 4 Capture High FEH xxxxxxxxB CCAP0L# Module 0 Capture Low EAH xxxxxxxxB CCAP1L# Module 1 Capture Low EBH xxxxxxxxB CCAP2L# Module 2 Capture Low ECH xxxxxxxxB CCAP3L# Module 3 Capture Low EDH xxxxxxxxB CCAP4L# Module 4 Capture Low EEH xxxxxxxxB

CCAPM0# Module 0 Mode DAH – ECOM CAPP CAPN MAT TOG PWM ECCF x0000000B CCAPM1# Module 1 Mode DBH – ECOM CAPP CAPN MAT TOG PWM ECCF x0000000B CCAPM2# Module 2 Mode DCH – ECOM CAPP CAPN MAT TOG PWM ECCF x0000000B CCAPM3# Module 3 Mode DDH – ECOM CAPP CAPN MAT TOG PWM ECCF x0000000B CCAPM4# Module 4 Mode DEH – ECOM CAPP CAPN MAT TOG PWM ECCF x0000000B

CCON*# PCA Counter Control D8H CF CR – CCF4 CCF3 CCF2 CCF1 CCF0 00x00000B CH# PCA Counter High F9H 00H CL# PCA Counter Low E9H 00H

CMOD# PCA Counter Mode D9H CIDL WDTE – – – CPS1 CPS0 ECF 00xxx000B DPTR: Data Pointer (2 bytes)

DPH Data Pointer High 83H 00H DPL Data Pointer Low 82H 00H

IE* Interrupt Enable A8H EA EC ET2 ES ET1 EX1 ET0 EX0 00H

IP* Interrupt Priority B8H – PPC PT2 PS PT1 PX1 PT0 PX0 x0000000B

IPH# Interrupt Priority High B7H – PPCH PT2H PSH PT1H PX1H PT0H PX0H x0000000B

DIRECT

ADDRESS

BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION MSB LSB

EXTRAM

(RX+ only)

DF DE DD DC DB DA D9 D8

AF AE AD AC AB AA A9 A8

BF BE BD BC BB BA B9 B8

B7 B6 B5 B4 B3 B2 B1 B0

AO xxxxxx00B

RESET VALUE

87 86 85 84 83 82 81 80

P0* Port 0 80H AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0 FFH

97 96 95 94 93 92 91 90

P1* Port 1 90H CEX4 CEX3 CEX2 CEX1 CEX0 ECI T2EX T2 FFH

A7 A6 A5 A4 A3 A2 A1 A0 P2* Port 2 A0H AD15 AD14 AD13 AD12 AD11 AD10 AD9 AD8 FFH

B7 B6 B5 B4 B3 B2 B1 B0 P3* Port 3 B0H RD WR T1 T0 INT1 INT0 TxD RxD FFH

PCON#1Power Control 87H SMOD1 SMOD0 – POF

* SFRs are bit addressable. # SFRs are modified from or added to the 80C51 SFRs. – Reserved bits.

1. Reset value depends on reset source.

2. Bit will not be affected by Reset.

3. LPEP – Low Power OTP–EPROM only operation.

2000 Aug 07

GF1 GF0 PD IDL 00xx0000B

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

8XC54/58

Table 2. 8XC51FA/FB/FC, 8XC51RA+/RB+/RC+/RD+ Special Function Registers (Continued)

SYMBOL DESCRIPTION

PSW* Program Status Word D0H CY AC F0 RS1 RS0 OV – P 000000x0B

RACAP2H# Timer 2 Capture High CBH 00H RACAP2L# Timer 2 Capture Low CAH 00H

SADDR# Slave Address A9H 00H SADEN# Slave Address Mask B9H 00H

SBUF Serial Data Buffer 99H xxxxxxxxB

SCON* Serial Control 98H SP Stack Pointer 81H 07H

TCON* Timer Control 88H TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0 00H

DIRECT

ADDRESS

BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION MSB LSB

D7 D6 D5 D4 D3 D2 D1 D0

9F 9E 9D 9C 9B 9A 99 98

SM0/FE

8F 8E 8D 8C 8B 8A 89 88

SM1 SM2 REN TB8 RB8 TI RI 00H

RESET VALUE

CF CE CD CC CB CA C9 C8 T2CON* Timer 2 Control C8H TF2 EXF2 RCLK TCLK EXEN2 TR2 C/T2 CP/RL2 00H T2MOD# Timer 2 Mode Control C9H – – – – – – T2OE DCEN xxxxxx00B

TH0 Timer High 0 8CH 00H TH1 Timer High 1 8DH 00H TH2# Timer High 2 CDH 00H TL0 Timer Low 0 8AH 00H TL1 Timer Low 1 8BH 00H TL2# Timer Low 2 CCH 00H

TMOD Timer Mode 89H GATE C/T M1 M0 GATE C/T M1 M0 00H WDTRST HDW Watchdog

Timer Reset (RX+ only)

* SFRs are bit addressable. # SFRs are modified from or added to the 80C51 SFRs. – Reserved bits.

OSCILLA T OR CHARACTERISTICS

XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier . The pins can be configured for use as an on-chip oscillator.

To drive the device from an external clock source, XTAL1 should be driven while XTAL2 is left unconnected. There are no requirements on the duty cycle of the external clock signal, because the input to the internal clock circuitry is through a divide-by-two flip-flop. However, minimum and maximum high and low times specified in the data sheet must be observed.

0A6H

RESET

A reset is accomplished by holding the RST pin high for at least two machine cycles (24 oscillator periods), while the oscillator is running. To insure a good power-on reset, the RST pin must be high long enough to allow the oscillator time to start up (normally a few milliseconds) plus two machine cycles. At power-on, the voltage on V

and RST must come up at the same time for a proper start-up.

Ports 1, 2, and 3 will asynchronously be driven to their reset condition when a voltage above V

(min.) is applied to RESET.

IH1

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

LOW POWER MODES Stop Clock Mode

The static design enables the clock speed to be reduced down to 0 MHz (stopped). When the oscillator is stopped, the RAM and Special Function Registers retain their values. This mode allows step-by-step utilization and permits reduced system power consumption by lowering the clock frequency down to any value. For lowest power consumption the Power Down mode is suggested.

Idle Mode

In the idle mode (see Table 3), the CPU puts itself to sleep while all of the on-chip peripherals stay active. The instruction to invoke the idle mode is the last instruction executed in the normal operating mode before the idle mode is activated. The CPU contents, the on-chip RAM, and all of the special function registers remain intact during this mode. The idle mode can be terminated either by any enabled interrupt (at which time the process is picked up at the interrupt service routine and continued), or by a hardware reset which starts the processor in the same manner as a power-on reset.

Power-Down Mode

To save even more power, a Power Down mode (see Table 3) can be invoked by software. In this mode, the oscillator is stopped and the instruction that invoked Power Down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values down to 2.0V and care must be taken to return V the minimum specified operating voltages before the Power Down Mode is terminated.

Either a hardware reset or external interrupt can be used to exit from Power Down. Reset redefines all the SFRs but does not change the on-chip RAM. An external interrupt allows both the SFRs and the on-chip RAM to retain their values.

To properly terminate Power Down the reset or external interrupt should not be executed before V operating level and must be held active long enough for the oscillator to restart and stabilize (normally less than 10ms).

With an external interrupt, INT0 and INT1 must be enabled and

configured as level-sensitive. Holding the pin low restarts the oscillator

but bringing the pin back high completes the exit. Once the interrupt is serviced, the next instruction to be executed after RETI will be the one following the instruction that put the device into Power Down.

is restored to its normal

LPEP

The LPEP bit (AUXR.4), only needs to be set for applications operating at V

less than 4V.

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

POWER OFF FLAG

The Power Off Flag (POF) is set by on-chip circuitry when the V level on the 8XC51FX/8XC51RX+ rises from 0 to 5V . The POF bit can be set or cleared by software allowing a user to determine if the reset is the result of a power-on or a warm start after powerdown. The V unaffected by the V

level must remain above 3V for the POF to remain

level.

Design Consideration

•When the idle mode is terminated by a hardware reset, the device

normally resumes program execution, from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the

possibility of an unexpected write when Idle is terminated by reset,

the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory.

ONCE Mode

The ONCE (“On-Circuit Emulation”) Mode facilitates testing and debugging of systems without the device having to be removed from the circuit. The ONCE Mode is invoked by:

1. Pull ALE low while the device is in reset and PSEN

2. Hold ALE low as RST is deactivated. While the device is in ONCE Mode, the Port 0 pins go into a float

state, and the other port pins and ALE and PSEN high. The oscillator circuit remains active. While the device is in this mode, an emulator or test CPU can be used to drive the circuit. Normal operation is restored when a normal reset is applied.

Programmable Clock-Out

A 50% duty cycle clock can be programmed to come out on P1.0. This pin, besides being a regular I/O pin, has two alternate functions. It can be programmed:

1. to input the external clock for Timer/Counter 2, or

2. to output a 50% duty cycle clock ranging from 61Hz to 4MHz at a 16MHz operating frequency.

To configure the Timer/Counter 2 as a clock generator, bit C/T T2CON) must be cleared and bit T20E in T2MOD must be set. Bit TR2 (T2CON.2) also must be set to start the timer.

The Clock-Out frequency depends on the oscillator frequency and the reload value of Timer 2 capture registers (RCAP2H, RCAP2L) as shown in this equation:

Oscillator Frequency

4 (65536 * RCAP2H, RCAP2L)

Where (RCAP2H,RCAP2L) = the content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer.

In the Clock-Out mode Timer 2 roll-overs will not generate an interrupt. This is similar to when it is used as a baud-rate generator. It is possible to use Timer 2 as a baud-rate generator and a clock generator simultaneously. Note, however, that the baud-rate and the Clock-Out frequency will be the same.

is high;

are weakly pulled

2 (in

Table 3. External Pin Status During Idle and Power-Down Mode

MODE PROGRAM MEMORY ALE PSEN PORT 0 PORT 1 PORT 2 PORT 3

Idle Internal 1 1 Data Data Data Data Idle External 1 1 Float Data Address Data Power-down Internal 0 0 Data Data Data Data Power-down External 0 0 Float Data Data Data

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

TIMER 2 OPERATION Timer 2

Timer 2 is a 16-bit Timer/Counter which can operate as either an event timer or an event counter, as selected by C/T function register T2CON (see Figure 1). Timer 2 has three operating modes: Capture, Auto-reload (up or down counting), and Baud Rate Generator, which are selected by bits in the T2CON as shown in Table 4.

2* in the special

Capture Mode

In the capture mode there are two options which are selected by bit EXEN2 in T2CON. If EXEN2=0, then timer 2 is a 16-bit timer or counter (as selected by C/T sets bit TF2, the timer 2 overflow bit. This bit can be used to generate an interrupt (by enabling the Timer 2 interrupt bit in the IE register). If EXEN2= 1, Timer 2 operates as described above, but with the added feature that a 1-to-0 transition at external input T2EX causes the current value in the Timer 2 registers, TL2 and TH2, to be captured into registers RCAP2L and RCAP2H, respectively. In addition, the transition at T2EX causes bit EXF2 in T2CON to be set, and EXF2 like TF2 can generate an interrupt (which vectors to the same location as Timer 2 overflow interrupt. The Timer 2 interrupt service routine can interrogate TF2 and EXF2 to determine which event caused the interrupt). The capture mode is illustrated in Figure 2. (There is no reload value for TL2 and TH2 in this mode. Even when a capture event occurs from T2EX, the counter keeps on counting T2EX pin transitions or osc/12 pulses.)

2* in T2CON) which, upon overflowing

Auto-Reload Mode (Up or Down Counter)

In the 16-bit auto-reload mode, Timer 2 can be configured (as either a timer or counter [C/T or down. The counting direction is determined by bit DCEN (Down Counter Enable) which is located in the T2MOD register (see

2* in T2CON]) then programmed to count up

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

Figure 3). When reset is applied the DCEN=0 which means Timer 2 will default to counting up. If DCEN bit is set, Timer 2 can count up or down depending on the value of the T2EX pin.

Figure 4 shows Timer 2 which will count up automatically since DCEN=0. In this mode there are two options selected by bit EXEN2 in T2CON register. If EXEN2=0, then T imer 2 counts up to 0FFFFH and sets the TF2 (Overflow Flag) bit upon overflow. This causes the Timer 2 registers to be reloaded with the 16-bit value in RCAP2L and RCAP2H. The values in RCAP2L and RCAP2H are preset by software means.

If EXEN2=1, then a 16-bit reload can be triggered either by an overflow or by a 1-to-0 transition at input T2EX. This transition also sets the EXF2 bit. The Timer 2 interrupt, if enabled, can be generated when either TF2 or EXF2 are 1.

In Figure 5 DCEN=1, which enables Timer 2 to count up or down. This mode allows pin T2EX to control the direction of count. When a logic 1 is applied at pin T2EX Timer 2 will count up. Timer 2 will overflow at 0FFFFH and set the TF2 flag, which can then generate an interrupt, if the interrupt is enabled. This timer overflow also causes the 16–bit value in RCAP2L and RCAP2H to be reloaded into the timer registers TL2 and TH2.

When a logic 0 is applied at pin T2EX this causes Timer 2 to count down. The timer will underflow when TL2 and TH2 become equal to the value stored in RCAP2L and RCAP2H. Timer 2 underflow sets the TF2 flag and causes 0FFFFH to be reloaded into the timer registers TL2 and TH2.

The external flag EXF2 toggles when Timer 2 underflows or overflows. This EXF2 bit can be used as a 17th bit of resolution if needed. The EXF2 flag does not generate an interrupt in this mode of operation.

(MSB) (LSB)

TF2 EXF2 RCLK TCLK EXEN2 TR2 C/T2

Symbol Position Name and Significance

TF2 T2CON.7 Timer 2 overflow flag set by a Timer 2 overflow and must be cleared by software. TF2 will not be set

EXF2 T2CON.6 Timer 2 external flag set when either a capture or reload is caused by a negative transition on T2EX and

RCLK T2CON.5 Receive clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its receive clock

TCLK T2CON.4 Transmit clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its transmit clock

EXEN2 T2CON.3 Timer 2 external enable flag. When set, allows a capture or reload to occur as a result of a negative

TR2 T2CON.2 Start/stop control for Timer 2. A logic 1 starts the timer. C/T2

CP/RL2

T2CON.1 Timer or counter select. (Timer 2)

T2CON.0 Capture/Reload flag. When set, captures will occur on negative transitions at T2EX if EXEN2 = 1. When

when either RCLK or TCLK = 1.

EXEN2 = 1. When Timer 2 interrupt is enabled, EXF2 = 1 will cause the CPU to vector to the Timer 2 interrupt routine. EXF2 must be cleared by software. EXF2 does not cause an interrupt in up/down counter mode (DCEN = 1).

in modes 1 and 3. RCLK = 0 causes Timer 1 overflow to be used for the receive clock.

in modes 1 and 3. TCLK = 0 causes Timer 1 overflows to be used for the transmit clock.

transition on T2EX if Timer 2 is not being used to clock the serial port. EXEN2 = 0 causes Timer 2 to ignore events at T2EX.

0 = Internal timer (OSC/12) 1 = External event counter (falling edge triggered).

cleared, auto-reloads will occur either with Timer 2 overflows or negative transitions at T2EX when EXEN2 = 1. When either RCLK = 1 or TCLK = 1, this bit is ignored and the timer is forced to auto-reload on Timer 2 overflow .

Figure 1. Timer/Counter 2 (T2CON) Control Register

CP/RL2

SU00728

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

8XC51RA+/RB+/RC+/RD+/80C51RA+

Table 4. Timer 2 Operating Modes

RCLK + TCLK CP/RL2 TR2 MODE

0 0 1 16-bit Auto-reload 0 1 1 16-bit Capture 1 X 1 Baud rate generator X X 0 (off)

OSC

T2 Pin

÷ 12

Transition

Detector

C/T2

= 0

= 1

TR2

Control

Capture

TL2

(8-bits)

RCAP2L RCAP2H

TH2

(8-bits)

8XC54/58

8XC51FA/FB/FC/80C51FA

TF2

Timer 2

Interrupt

T2EX Pin

Control

EXEN2

EXF2

SU00066

Figure 2. Timer 2 in Capture Mode

T2MOD Address = 0C9H Reset Value = XXXX XX00B

Not Bit Addressable

— — — — — — T2OE DCEN

Bit

76543210

Symbol Function

— Not implemented, reserved for future use.* T2OE Timer 2 Output Enable bit. DCEN Down Count Enable bit. When set, this allows Timer 2 to be configured as an up/down counter.

* User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features.

In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate.

SU00729

Figure 3. Timer 2 Mode (T2MOD) Control Register

2000 Aug 07

Philips Semiconductors Product specification

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

OSC

T2 PIN

T2EX PIN

÷ 12

TRANSITION

DETECTOR

C/T2 = 0

= 1

C/T2

EXEN2

CONTROL

TR2

CONTROL

RELOAD

TL2

(8-BITS)

RCAP2L RCAP2H

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

TH2

(8-BITS)

TF2

EXF2

8XC54/58

TIMER 2

INTERRUPT

SU00067

OSC

T2 PIN

÷12

C/T2 = 0

= 1

C/T2

Figure 4. Timer 2 in Auto-Reload Mode (DCEN = 0)

(DOWN COUNTING RELOAD VALUE)

FFH FFH

OVERFLOW

TL2 TH2

CONTROL

TR2

RCAP2L RCAP2H

(UP COUNTING RELOAD VALUE) T2EX PIN

Figure 5. Timer 2 Auto Reload Mode (DCEN = 1)

TOGGLE

COUNT DIRECTION 1 = UP 0 = DOWN

TF2

EXF2

INTERRUPT

SU00730

2000 Aug 07

Philips Semiconductors Product specification

Baud Rate

Osc Freq

80C51 8-bit microcontroller family 8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V), low power, high speed (33MHz)

NOTE: OSC. Freq. is divided by 2, not 12.

OSC

T2 Pin

T2EX Pin

÷ 2

Transition

Detector

C/T2 = 0

C/T2

= 1

TR2

Control

EXF2

TL2

(8-bits)

RCAP2L RCAP2H

Timer 2 Interrupt

TH2

(8-bits)

8XC54/58

8XC51FA/FB/FC/80C51FA

8XC51RA+/RB+/RC+/RD+/80C51RA+

Timer 1

Overflow

÷ 2

“0” “1”

SMOD

RCLK

÷ 16

÷ 16 TX Clock

RX Clock

TCLK

Reload

“0”“1”

Control

EXEN2

Note availability of additional external interrupt.

Figure 6. Timer 2 in Baud Rate Generator Mode

Table 5. Timer 2 Generated Commonly Used

Baud Rates

Timer 2

RCAP2H RCAP2L

375K 12MHz FF FF

9.6K 12MHz FF D9

2.8K 12MHz FF B2

2.4K 12MHz FF 64

1.2K 12MHz FE C8 300 12MHz FB 1E 110 12MHz F2 AF 300 6MHz FD 8F 110 6MHz F9 57

Baud Rate Generator Mode

Bits TCLK and/or RCLK in T2CON (Table 5) allow the serial port transmit and receive baud rates to be derived from either Timer 1 or Timer 2. When TCLK= 0, Timer 1 is used as the serial port transmit baud rate generator . When TCLK= 1, Timer 2 is used as the serial port transmit baud rate generator. RCLK has the same effect for the serial port receive baud rate. With these two bits, the serial port can have different receive and transmit baud rates – one generated by Timer 1, the other by Timer 2.

Figure 6 shows the Timer 2 in baud rate generation mode. The baud rate generation mode is like the auto-reload mode,in that a rollover in TH2 causes the Timer 2 registers to be reloaded with the 16-bit value in registers RCAP2H and RCAP2L, which are preset by software.

SU00068

The baud rates in modes 1 and 3 are determined by Timer 2’s overflow rate given below:

Modes 1 and 3 Baud Rates +

Timer 2 Overflow Rate

The timer can be configured for either “timer” or “counter” operation. In many applications, it is configured for “timer” operation (C/T

2*=0). Timer operation is different for Timer 2 when it is being used as a baud rate generator.

Usually, as a timer it would increment every machine cycle (i.e., 1/12 the oscillator frequency). As a baud rate generator, it increments every state time (i.e., 1/2 the oscillator frequency). Thus the baud rate formula is as follows:

Modes 1 and 3 Baud Rates =

Oscillator Frequency

[32 [65536 * (RCAP2H, RCAP2L)]]

Where: (RCAP2H, RCAP2L)= The content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer.

The Timer 2 as a baud rate generator mode shown in Figure 6, is valid only if RCLK and/or TCLK = 1 in T2CON register. Note that a rollover in TH2 does not set TF2, and will not generate an interrupt. Thus, the Timer 2 interrupt does not have to be disabled when Timer 2 is in the baud rate generator mode. Also if the EXEN2 (T2 external enable flag) is set, a 1-to-0 transition in T2EX (Timer/counter 2 trigger input) will set EXF2 (T2 external flag) but will not cause a reload from (RCAP2H, RCAP2L) to (TH2,TL2). Therefore when Timer 2 is in use as a baud rate generator, T2EX can be used as an additional external interrupt, if needed.

2000 Aug 07

+ 39 hidden pages