Datasheet EM78P156ELP, EM78P156ELM, EM78P156ELKM, EM78P156ELAS Datasheet (ELAN)

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EM78P156EL

OTP ROM

1. GENERAL DESCRIPTION

EM78P156EL is an 8-bit microprocessor designed and developed with low-power and high-speed CMOS technology. It is equipped with 1K*13-bits Electrical One Time Programmable Read Only Memory (OTP-ROM). It provides a PROTECTION bit to prevent user’s code in the OTP memory from being intruded. 6 OPTION bits are also available to meet user’s requirements.

With its OTP-ROM feature, the EM78P156EL is able to offer a convenient way of developing and verifying user’s programs. Moreover, user can take advantage of EMC Writer to easily program his development code.

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2. FEATURES

• Operating voltage range : 2.3V~5.5V

• Operating temperature range: 0°C~70°C

• Operating frequency rang (base on 2 clocks ): * Crystal mode: DC~20MHz at 5V, DC~8MHz at 3V, DC~4MHz at 2.3V. * ERC mode: DC~4MHz at 5V, DC~4MHz at 3V, DC~4MHz at 2.3V.

• Low power consumption: * Less then 1.6 mA at 5V/4MHz

EM78P156EL

OTP ROM

* Typically 15 µA at 3V/32KHz * Typically 1 µA during sleep mode

• 1K × 13 bits on chip ROM

• One security register to prevent intrusion of OTP memory codes

• One configuration register to accommodate user’s requirements

• 48× 8 bits on chip registers (SRAM, general purpose register)

• 2 bi-directional I/O ports

• 5 level stacks for subroutine nesting

• 8-bit real time clock/counter (TCC) with selective signal sources, trigger edges, and overflow interrupt

• Two clocks per instruction cycle

• Power down (SLEEP) mode

• Three available interruptions * TCC overflow interrupt * Input-port status changed interrupt (wake up from sleep mode) * External interrupt

• Programmable free running watchdog timer

• 8 programmable pull-high pins

• 7 programmable pull-down pins

• 8 programmable open-drain pins

• 2 programmable R-option pins

• Package types: * 18 pin DIP 300mil : EM78P156ELP * 18 pin SOP(SOIC) 300mil : EM78P156ELM

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EM78P156EL

* 20 pin SSOP 209mil : EM78P156ELAS * 20 pin SSOP 209mil : EM78P156ELKM

• 99.9% single instruction cycle commands

• The transient point of system frequency between HXT and LXT is around 400KHz

OTP ROM

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3. PIN ASSIGNMENTS

VSS

unter (with Schmitt trigger input pin), must be tied to

* Input pin with Schmitt trigger. If this pin remains at logic low, the controller

EM78P156EL

OTP ROM

/RESET

P60//INT

EM78P156ELP

EM78P156ELM

P52 P53

TCC

P61 P62 P63

1 2 3 4 5 6 7 8 9

DIP SOP

SOIC

18 17 16 15 14 13 12 11 10

P51 P50 OSCI OSCO VDD P67 P66 P65 P64

/RESET

EM78P156ELAS

NC P52 P53

TCC

P61 P62 P63

1 2 3 4 5 6 7 8 9 10

SSOP

Fig. 1 Pin Assignment

Table 1 EM78P156ELP and EM78P156ELM Pin Description

Symbol Pin No. Type Function

VDD 14 - * Power supply. OSCI 16 I

* XTAL type: Crystal input terminal or external clock input pin. * ERC type: RC oscillator input pin. * XTAL type: Output terminal for crystal oscillator or external clock input pin.

OSCO 15 I/O

* RC type: Instruction clock output. * External clock signal input.

TCC 3 I /RESET 4 I

P50~P53

17, 18,

1, 2

I/O

P60~P67 6~13 I/O

* The real time clock/co VDD or VSS if not in use.

will also remain in reset condition. * P50~P53 are bi-directional I/O pins. * P50 and P51 can also be defined as the R-option pins. * P50~P52 can be pulled-down by software. * P60~P67 are bi-directional I/O pins. * These can be pulled-high or can be open-drain by software programming.

* P60~P63 can also be pulled-down by software. /INT 6 I * External interrupt pin triggered by falling edge. VSS 5 - * Ground.

20 19 18 17 16 15 14 13 12 11

EM78P156ELKM

NC P51 P50 OSCI OSCO VDD P67 P60//INT P66 P65 P64

P52 P53

TCC

/RESET

P61 P62 P63

1 2 3 4 5 6 7 8 9 10

SSOP

20 19 18 17 16 15 14 13 12 11

P51 P50 OSCI OSCO VDD VDD P67 P60//INT P66 P65 P64

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Table 2 EM78P156ELAS Pin Description

* The real time clock/counter (with Schmitt trigger input pin), must be tied to * Input pin with Schmitt trigger. If this pin remains at logic low, the controller

drain by software programming.

* The real time clock/counter (with Schmitt trigger input pin), must be tied to

drain by software programming.

Symbol Pin No. Type Function

VDD 15 - * Power supply. OSCI 17 I

OSCO 16 I/O

* XTAL type: Crystal input terminal or external clock input pin.

* ERC type: RC oscillator input pin.

* XTAL type: Output terminal for crystal oscillator or external clock input pin.

* RC type: Instruction clock output.

* External clock signal input.

EM78P156EL

OTP ROM

TCC 4 I /RESET 5 I

P50~P53

P60~P67 7~14 I/O

/INT 7 I * External interrupt pin triggered by falling edge. VSS 6 - * Ground.

Table 3 EM78P156ELKM Pin Description

Symbol Pin No. Type Function

VDD 15,16 - * Power supply. OSCI 18 I

OSCO 17 I/O

TCC 3 I /RESET 4 I

P50~P53

P60~P67 7~14 I/O

/INT 7 I * External interrupt pin triggered by falling edge. VSS 5, 6 - * Ground.

18, 19,

2, 3

19, 20,

1, 2

I/O

VDD or VSS if not in use.

will also remain in reset condition.

* P50~P53 are bi-directional I/O pins.

* P50 and P51 can also be defined as the R-option pins.

* P50~P52 can be pulled-down by software.

* P60~P67 are bi-directional I/O pins.

* These can be pulled-high or can be open-

* P60~P63 can also be pulled-down by software.

* XTAL type: Crystal input terminal or external clock input pin.

* ERC type: RC oscillator input pin.

* XTAL type: Output terminal for crystal oscillator or external clock input pin.

* RC type: Instruction clock output.

* External clock signal input.

VDD or VSS if not in use.

* Input pin with Schmitt trigger. If this pin remains at logic low, the controll

will also remain in reset condition.

* P50~P53 are bi-directional I/O pins.

* P50 and P51 can also be defined as the R-option pins.

* P50~P52 can be pulled-down by software.

* P60~P67 are bi-directional I/O pins.

* These can be pulled-high or can be open-

* P60~P63 can also be pulled-down by software.

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4. FUNCTION DESCRIPTION

& Wake

OSCI OSCO /RESET

WDT Timer

Oscillator/Timing

Control

Internal C External R

oscillator

WDT

Time-out

Prescale

R1(TCC)

IOCA

Interrupt Control

EM78P156EL

OTP ROM

/INT TCC

STACK 1 STACK 2

STACK 3 STACK 4 STACK 5

ALU

ROM

Instruction

P C

Sleep

Control

P 5 0

IOC5

RAM

P 5 3

DATA & CONTROL BUS

Instruction

Decoder

IOC6

Fig. 2 Function Block Diagram

4.1 Operational Registers

1. R0 (Indirect Addressing Register)

R0 is not a physically implemented register. Its major function is to perform as an indirect addressing pointer. Any instruction using R0 as a pointer actually accesses data pointed by the RAM Select

2. R1 (Time Clock /Counter)

• Increased by an external signal edge, which is defined by TE bit (CONT-4) through the TCC pin, or by the instruction cycle clock.

• Writable and readable as any other registers.

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EM78P156EL

OTP ROM

• Defined by resetting PAB(CONT-3).

• The prescaler is assigned to TCC, if the PAB bit (CONT-3) is reset.

• The contents of the prescaler counter will be cleared only when TCC register is written with a value.

3. R2 (Program Counter) & Stack

• Depending on the device type, R2 and hardware stack are 10-bit wide. The structure is depicted in Fig.3.

• Generating 1024×13 bits on-chip OTP ROM addresses to the relative programming instruction codes. One program page is 1024 words long.

• R2 is set as all "0"s when under RESET condition.

• "JMP" instruction allows direct loading of the lower 10 program counter bits. Thus, "JMP" allows PC to go to any location within a page.

• "CALL" instruction loads the lower 10 bits of the PC, and then PC+1 is pushed into the stack. Thus, the subroutine entry address can be located anywhere within a page.

• "RET" ("RETL k", "RETI") instruction loads the program counter with the contents of the top-level stack.

• "ADD R2, A" allows the contents of ‘A’ to be added to the current PC, and the ninth and tenth bits of the PC are cleared.

• "MOV R2, A" allows to load an address from the "A" register to the lower 8 bits of the PC, and the ninth and tenth bits of the PC are cleared.

• Any instruction that writes to R2 (e.g., "ADD R2,A", "MOV R2,A", "BC R2,6",⋅⋅⋅⋅⋅) will cause the ninth and tenth bits (A8~A9) of the PC to be cleared. Thus, the computed jump is limited to the first 256

locations of a page.

• All instruction are single instruction cycle (fclk/2 or fclk/4) except for the instruction that would change the contents of R2. Such instruction will need one more instruction cycle.

A9 A8 A7 ~ A0

000

CALL RET

RETL RETL K

Stack 1 Stack 2 Stack 3

Stack 4 Stack 5

PAGE 0

3FF

Fig. 3 Program Counter Organization

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00 R0

EM78P156EL

OTP ROM

01 02 03 04

05 06 07 08

09 0A 0B 0C 0D 0E 0F

R1(TCC) R2(PC) R3(Status) R4(RSR)

R5(Port5) R6(Port6)

RF R10

Stack (5 level)

IOC5 IOC6

IOCA IOCB IOCC IOCD IOCE IOCF

: : :

48x8 Common Register

R3F

Fig. 4 Data Memory Configuration

4. R3 (Status Register)

7 6 5 4 3 2 1 0

GP2 GP1 GP0 T P Z DC C

• Bit 0 (C) Carry flag

• Bit 1 (DC) Auxiliary carry flag

• Bit 2 (Z) Zero flag.

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EM78P156EL

OTP ROM

Set to "1" if the result of an arithmetic or logic operation is zero.

• Bit 3 (P) Power down bit. Set to 1 during power on or by a "WDTC" command and reset to 0 by a "SLEP" command.

• Bit 4 (T) Time-out bit. Set to 1 with the "SLEP" and "WDTC" commands, or during power up and reset to 0 by WDT time-out.

• Bit5 ~7 (GP0 ~ 2) General-purpose read/write bits.

5. R4 (RAM Select Register)

• Bits 0~5 are used to select registers (address: 00~06, 0F~3F) in the indirect addressing mode.

• Bits 6~7 are not used (read only).

• The Bits 6~7 set to “1” at all time.

• Z flag of R3 will set to “1” when R4 content is equal to “3F.” When R4=R4+1, R4 content will select

as R0.

• See the configuration of the data memory in Fig. 4.

6. R5 ~ R6 (Port 5 ~ Port 6)

• R5 and R6 are I/O registers.

• Only the lower 4 bits of R5 are available.

7. RF (Interrupt Status Register)

7 6 5 4 3 2 1 0

- - - - - EXIF ICIF TCIF

“1” means interrupt request, and “0” means no interrupt occurs.

• Bit 0 (TCIF) TCC overflow interrupt flag. Set when TCC overflows, reset by software.

• Bit 1 (ICIF) Port 6 input status change interrupt flag. Set when Port 6 input changes, reset by

software.

• Bit 2 (EXIF) External interrupt flag. Set by falling edge on /INT pin, reset by software.

• Bits 3 ~ 7 Not used.

• RF can be cleared by instruction but cannot be set.

• IOCF is the interrupt mask register.

• Note that the result of reading RF is the "logic AND" of RF and IOCF.

8. R10 ~ R3F

• All of these are 8-bit general-purpose registers.

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4.2 Special Purpose Registers

1. A (Accumulator)

• Internal data transfer, or instruction operand holding

• It cannot be addressed.

2. CONT (Control Register)

7 6 5 4 3 2 1 0

- /INT TS TE PAB PSR2 PSR1 PSR0

• Bit 0 (PSR0) ~ Bit 2 (PSR2) TCC/WDT prescaler bits.

PSR2 PSR1 PSR0 TCC Rate WDT Rate

0 0 0 1:2 1:1 0 0 1 1:4 1:2 0 1 0 1:8 1:4 0 1 1 1:16 1:8 1 0 0 1:32 1:16 1 0 1 1:64 1:32 1 1 0 1:128 1:64 1 1 1 1:256 1:128

EM78P156EL

OTP ROM

• Bit 3 (PAB) Prescaler assignment bit. 0: TCC 1: WDT

• Bit 4 (TE) TCC signal edge 0: increment if the transition from low to high takes place on TCC pin 1: increment if the transition from high to low takes place on TCC pin

• Bit 5 (TS) TCC signal source 0: internal instruction cycle clock 1: transition on TCC pin

• Bit 6 (/INT) Interrupt enable flag 0: masked by DISI or hardware interrupt 1: enabled by ENI/RETI instructions

• Bit 7 Not used.

• CONT register is both readable and writable.

3. IOC5 ~ IOC6 (I/O Port Control Register)

• "1" put the relative I/O pin into high impedance, while "0" defines the relative I/O pin as output.

• Only the lower 4 bits of IOC5 can be defined.

• IOC5 and IOC6 registers are both readable and writable.

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EM78P156EL

4. IOCA (Prescaler Counter Register)

• IOCA register is readable.

• The value of IOCA is equal to the contents of Prescaler counter.

• Down counter.

5. IOCB (Pull-down Control Register)

7 6 5 4 3 2 1 0

/PD7 /PD6 /PD5 /PD4 - /PD2 /PD1 /PD0

• Bit 0 (/PD0) Control bit is used to enable the pull-down of P50 pin. 0: Enable internal pull-down 1: Disable internal pull-down

• Bit 1 (/PD1) Control bit is used to enable the pull-down of P51 pin.

OTP ROM

• Bit 2 (/PD2) Control bit is used to enable the pull-down of P52 pin.

• Bit 3 Not used.

• Bit 4 (/PD4) Control bit is used to enable the pull-down of P60 pin.

• Bit 5 (/PD5) Control bit is used to enable the pull-down of P61 pin.

• Bit 6 (/PD6) Control bit is used to enable the pull-down of P62 pin.

• Bit 7 (/PD7) Control bit is used to enable the pull-down of P63 pin.

• IOCB Register is both readable and writable.

6. IOCC (Open-drain Control Register)

7 6 5 4 3 2 1 0

OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0

• Bit 0 (OD0) Control bit is used to enable the open-drain of P60 pin. 0: Disable open-drain output 1: Enable open-drain output

• Bit 1 (OD1) Control bit is used to enable the open-drain of P61 pin.

• Bit 2 (OD2) Control bit is used to enable the open-drain of P62 pin.

• Bit 3 (OD3) Control bit is used to enable the open-drain of P63 pin.

• Bit 4 (OD4) Control bit is used to enable the open-drain of P64 pin.

• Bit 5 (OD5) Control bit is used to enable the open-drain of P65 pin.

• Bit 6 (OD6) Control bit is used to enable the open-drain of P66 pin.

• Bit 7 (OD7) Control bit is used to enable the open-drain of P67 pin.

• IOCC Register is both readable and writable.

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EM78P156EL

7. IOCD (Pull-high Control Register)

7 6 5 4 3 2 1 0

/PH7 /PH6 /PH5 /PH4 /PH3 /PH2 /PH1 /PH0

• Bit 0 (/PH0) Control bit is used to enable the pull-high of P60 pin. 0: Enable internal pull-high 1: Disable internal pull-high

• Bit 1 (/PH1) Control bit is used to enable the pull-high of P61 pin.

• Bit 2 (/PH2) Control bit is used to enable the pull-high of P62 pin.

• Bit 3 (/PH3) Control bit is used to enable the pull-high of P63 pin.

• Bit 4 (/PH4) Control bit is used to enable the pull-high of P64 pin.

• Bit 5 (/PH5) Control bit is used to enable the pull-high of P65 pin.

OTP ROM

• Bit 6 (/PH6) Control bit is used to enable the pull-high of P66 pin.

• Bit 7 (/PH7) Control bit is used to enable the pull-high of P67 pin.

• IOCD Register is both readable and writable.

8. IOCE (WDT Control Register)

7 6 5 4 3 2 1 0

WDTE EIS - ROC - - - -

• Bit 7 (WDTE) Control bit used to enable Watchdog timer. 0: Disable WDT. 1: Enable WDT. WDTE is both readable and writable.

• Bit 6 (EIS) Control bit is used to define the function of P60 (/INT) pin. 0: P60, bi-directional I/O pin. 1: /INT, external interrupt pin. In this case, the I/O control bit of P60 (bit 0 of IOC6) must be set to "1". When EIS is "0", the path of /INT is masked. When EIS is "1", the status of /INT pin can also be read by way of reading Port 6 (R6). Refer to Fig. 7(a). EIS is both readable and writable.

• Bit 4 (ROC) ROC is used for the R-option. Setting the ROC to "1" will enable the status of R-option pins (P50∼P51) that are read by the controller. Clearing the ROC will disable the R-option function. If the R-option function is selected, user must connect the P51 pin or/and P50 pin to VSS with a 430KΩ external resistor (Rex). If the

Rex is connected/disconnected, the status of P50 (P51) is read as "0"/"1". Refer to Fig. 8.

• Bits 0~3,5 Not used.

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9. IOCF (Interrupt Mask Register)

7 6 5 4 3 2 1 0

- - - - - EXIE ICIE TCIE

• Bit 0 (TCIE) TCIF interrupt enable bit. 0: disable TCIF interrupt 1: enable TCIF interrupt

• Bit 1 (ICIE) ICIF interrupt enable bit. 0: disable ICIF interrupt 1: enable ICIF interrupt

• Bit 2 (EXIE) EXIF interrupt enable bit. 0: disable EXIF interrupt

EM78P156EL

OTP ROM

1: enable EXIF interrupt

• Bits 3~7 Not used.

• Individual interrupt is enabled by setting its associated control bit in the IOCF to "1".

• Global interrupt is enabled by the ENI instruction and is disabled by the DISI instruction. Refer to Fig.

10.

• IOCF register is both readable and writable.

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EM78P156EL

PSR0~PSR2

WDT time-out

CLK(=Fosc/2 or Fosc/4)

WTE

OTP ROM

4.3 TCC/WDT & Prescaler

An 8-bit counter available as prescaler for the TCC or WDT. The prescaler is available for either the TCC or WDT only at any given time, and the PAB bit of the CONT register is used to determine the prescaler assignment. The PSR0~PSR2 bits determine the ratio. The prescaler is cleared each time the instruction is written to TCC under TCC mode. The WDT and prescaler, when assigned to WDT mode, are cleared by the “WDTC” or “SLEP” instructions. Fig. 5 depicts the circuit diagram of TCC/WDT.

• R1 (TCC) is an 8-bit timer/counter. The clock source of TCC can be internal or external clock input (edge selectable from TCC pin). If TCC signal source is from internal clock, TCC will increase by 1 at every instruction cycle (without prescaler). Referring to Fig. 5, CLK=Fosc/2 or CLK=Fosc/4 application is determined by the CODE Option bit CLK status. CLK=Fosc/2 is used if CLK bit is "0", and CLK=Fosc/4 is used if CLK bit is "1". If TCC signal source comes from external clock input, TCC is increased by 1 at every falling edge or rising edge of TCC pin.

• The watchdog timer is a free running on-chip RC oscillator. The WDT will keep on running even when the oscillator driver has been turned off (i.e. in sleep mode). During normal operation or sleep mode, a WDT time-out (if enabled) will cause the device to reset. The WDT can be enabled or disabled any time during normal mode by software programming. Refer to WDTE bit of IOCE register. Without prescaler, the WDT time-out period is approximately 18 ms1 (default).

TCC

(in IOCE)

WDT

PAB

SYNC 2 cycles

8-bit Counter

8-to-1 MUX

Data Bus

TCC (R1)

TCC overflow interrupt

PAB

IOCA M

Initial value

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Fig. 5 Block Diagram of TCC and WDT

<Note>: Vdd = 5V, set up time period = 16.5ms ± 5%

Vdd = 3V, set up time period = 18ms ± 5%

MUX

PAB

Page 15

EM78P156EL

OTP ROM

4.4 I/O Ports

The I/O registers, both Port 5 and Port 6, are bi-directional tri-state I/O ports. Port 6 can be pulled high internally by software. In addition, Port 6 can also have open-drain output by software. Input status change interrupt (or wake-up) function on Port 6. P50 ~ P52 and P60 ~ P63 pins can be pulled down by software. Each I/O pin can be defined as "input" or "output" pin by the I/O control register (IOC5 ~ IOC6). P50~P51 are the R-option pins enabled by setting the ROC bit in the IOCE register to 1. When the R-option function is used, it is recommended that P50~P51 are used as output pins. When R-option is in enable state, P50~P51 must be programmed as input pins. Under R-option mode, the current/power consumption by Rex should be taken into the consideration to promote energy conservation.

The I/O registers and I/O control registers are both readable and writable. The I/O interface circuits for Port 5 and Port 6 are shown in the following Figures 6, 7(a), 7(b), and Figure 8.

PCRD

PORT

_ Q

M U

CLK

C L

P R

CLK C L

PCWR

PDWR

PDRD

NOTE: Pull-down is not shown in the figure.

IOD

Fig. 6 The Circuit of I/O Port and I/O Control Register for Port 5

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Q _ Q

PCRD

P R

CLK

C L

EM78P156EL

OTP ROM

PCWR

P60 /INT

PORT

Bit 6 of IOCE

CLK

INT

PDWR

CLK

U X

PDRD

CLK

IOD

T10

NOTE: Pull-high (down) and Open-drain are not shown in the figure.

Fig. 7(a) The Circuit of I/O Port and I/O Control Register for P60 (/INT)

PCRD

R _ Q

CLK C L

PCWR

P61~P67

PORT

CLK C L

_ Q

PDWR

PDRD

_ Q

M U

CLK

C L

IOD

TIN

NOTE: Pull-high (down) and Open-drain are not shown in the figure.

Fig. 7(b) The Circuit of I/O Port and I/O Control Register for P61~P67

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T10 T11

T17

/SLEP

IOCE.1

CLK

EM78P156EL

OTP ROM

CLK

RE.1

P R

C L

_ Q

CLK

(Wake-up from SLEEP)

Interrupt

ENI Instruction

DISI Instruction

Interrupt

Next Instruction

(Wake-up from SLEEP)

Fig. 7(c) Block Diagram of I/O Port 6 with Input Change Interrupt/Wake-up

Table 4 Usage of Port 6 Input Change Wake-up/Interrupt Function

Usage of Port 6 input status changed Wake-up/Interrupt

(I) Wake-up from Port 6 Input Status Change (II) Port 6 Input Status Change Interrupt

(a) Before SLEEP 1. Read I/O Port 6 (MOV R6,R6)

1. Disable WDT1 (using very carefully) 2. Execute "ENI"

2. Read I/O Port 6 (MOV R6,R6) 3. Enable interrupt (Set IOCF.1)

3. Execute "ENI" or "DISI" 4. IF Port 6 change (interrupt)

4. Enable interrupt (Set IOCF.1) → Interrupt vector (008H)

5. Execute "SLEP" instruction

(b) After Wake-up

1. IF "ENI" → Interrupt vector (008H)

2. IF "DISI" → Next instruction

NOTE: Software disables WDT (watchdog timer) but hardware must be enabled before applying

Port 6 Change Wake-Up function. (CODE Option Register and Bit 11 (ENWDTB-) set to “1”).

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ROC

PCRD

PCWR

IOD

PDWR

PDRD

Weakly PORT

CLK

Q Q D

Pull-up

VCC

EM78P156EL

OTP ROM

P R

C L

P R

C L

Rex*

*The Rex is 430K ohm external resistor

Fig. 8 The Circuit of I/O Port with R-option(P50,P51)

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4.5 RESET and Wake-up

1. RESET

A RESET is initiated by one of the following events-

(1) Power on reset. (2) /RESET pin input "low", or (3) WDT time-out (if enabled).

The device is kept in a RESET condition for a period of approx. 18ms1 (one oscillator start-up timer period) after the reset is detected. Once the RESET occurs, the following functions are performed. Refer to Fig.9.

• The oscillator is running, or will be started.

EM78P156EL

OTP ROM

• The Program Counter (R2) is set to all "0".

• All I/O port pins are configured as input mode (high-impedance state).

• The Watchdog timer and prescaler are cleared.

• When power is switched on, the upper 3 bits of R3 are cleared.

• The bits of the CONT register are set to all "1" except for the Bit 6 (INT flag).

• The bits of the IOCA register are set to all "1".

• The bits of the IOCB register are set to all "1".

• The IOCC register is cleared.

• The bits of the IOCD register are set to all "1".

• Bit 7 of the IOCE register is set to "1", and Bits 4 and 6 are cleared.

• Bits 0~2 of RF and bits 0~2 of IOCF register are cleared.

The sleep (power down) mode is asserted by executing the “SLEP” instruction. While entering sleep mode, WDT (if enabled) is cleared but keeps on running. The controller can be awakened by-

(1) External reset input on /RESET pin, (2) WDT time-out (if enabled), or (3) Port 6 input status changes (if enabled).

The first two cases will cause the EM78P156EL to reset. The T and P flags of R3 can be used to determine the source of the reset (wake-up). The last case is considered the continuation of program execution and the global interrupt ("ENI" or "DISI" being executed) decides whether or not the

NOTE: Vdd = 5V, set up time period = 16.8ms ± 5%

Vdd = 3V, set up time period = 19ms ± 5%

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EM78P156EL

OTP ROM

controller branches to the interrupt vector following wake-up. If ENI is executed before SLEP, the instruction will begin to execute from the address 008H after wake-up. If DISI is executed before SLEP, the operation will restart from the succeeding instruction right next to SLEP after wake-up.

Only one of Cases 2 and 3 can be enabled before entering the sleep mode. That is,

[a] if Port 6 Input Status Change Interrupt is enabled before SLEP , WDT must be disabled. by

software. However, the WDT bit in the option register remains enabled. Hence, the EM78P156EL can be awakened only by Case 1 or 3.

[b] if WDT is enabled before SLEP, Port 6 Input Status Change Interrupt must be disabled. Hence,

the EM78P156EL can be awakened only by Case 1 or 2. Refer to the section on Interrupt.

If Port 6 Input Status Change Interrupt is used to wake-up the EM78P156EL (Case [a] above), the following instructions must be executed before SLEP:

MOV A, @xx000110b ; Select internal TCC clock CONTW CLR R1 ; Clear TCC and prescaler MOV A, @xxxx1110b ; Select WDT prescaler CONTW WDTC ; Clear WDT and prescaler MOV A, @0xxxxxxxb ; Disable WDT IOW RE MOV R6, R6 ; Read Port 6 MOV A, @00000x1xb ; Enable Port 6 input change interrupt IOW RF ENI (or DISI) ; Enable (or disable) global interrupt SLEP ; Sleep NOP

One problem user should be aware of, is that after waking up from the sleep mode, WDT would enable automatically. The WDT operation (being enabled or disabled) should be handled appropriately by software after waking up from the sleep mode.

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Table 5 The Summary of the Initialized Values for Registers

Address Name Reset Type Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Bit Name X X X X C53 C52 C51 C50

N/A IOC5

Wake-Up from Pin Change U U U U P P P P

N/A IOC6

Wake-Up from Pin Change P P P P P P P P

N/A CONT

Wake-Up from Pin Change P P P P P P P P

0x00 R0(IAR)

Wake-Up from Pin Change P P P P P P P P

0x01 R1(TCC)

Wake-Up from Pin Change P P P P P P P P

0x02 R2(PC)

Wake-Up from Pin Change **0/P **0/P **0/P **0/P **1/P **0/P **0/P **0/P

0x03 R3(SR)

Wake-Up from Pin Change P P P t t P P P

0x04 R4(RSR)

Wake-Up from Pin Change 1 1 P P P P P P

0x05 P5

Wake-Up from Pin Change 0 0 0 0 P P P P

0x06 P6

Power-On U U U U 1 1 1 1

/RESET and WDT U U U U 1 1 1 1

Bit Name C67 C66 C65 C64 C63 C62 C61 C60

Power-On 1 1 1 1 1 1 1 1

/RESET and WDT 1 1 1 1 1 1 1 1

Bit Name X /INT TS TE PAB PSR2 PSR1 PSR0

Power-On 1 0 1 1 1 1 1 1

/RESET and WDT 1 0 1 1 1 1 1 1

Bit Name - - - - - - - -

Power-On U U U U U U U U

/RESET and WDT P P P P P P P P

Bit Name - - - - - - - -

Power-On 0 0 0 0 0 0 0 0

/RESET and WDT 0 0 0 0 0 0 0 0

Bit Name - - - - - - - -

Power-On 0 0 0 0 0 0 0 0

/RESET and WDT 0 0 0 0 0 0 0 0

Bit Name GP2 GP1 GP0 T P Z DC C

Power-On 0 0 0 1 1 U U U

/RESET and WDT 0 0 0 t t P P P

Bit Name - - - - - - - -

Power-On 1 1 U U U U U U

/RESET and WDT 1 1 P P P P P P

Bit Name X X X X P53 P52 P51 P50

Power-On 0 0 0 0 U U U U

/RESET and WDT 0 0 0 0 P P P P

Bit Name P67 P66 P65 P64 P63 P62 P61 P60

Power-On U U U U U U U U

/RESET and WDT P P P P P P P P

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Address Name Reset Type Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

0x0F RF(ISR)

0x0A IOCA

0x0B IOCB

0x0C IOCC

0x0D IOCD

0x0E IOCE

0x0F IOCF

0x10~0x2F R10~R2F

** To jump address 0x08, or to execute the instruction which is next to the “SLEP” instruction.

Wake-Up from Pin Change P P P P P P P P

Bit Name X X X X X EXIF ICIF TCIF

Power-On U U U U U 0 0 0

/RESET and WDT U U U U U 0 0 0

Wake-Up from Pin Change U U U U U P P P

Bit Name - - - - - - - -

Power-On 1 1 1 1 1 1 1 1

/RESET and WDT 1 1 1 1 1 1 1 1

Wake-Up from Pin Change P P P P P P P P

Bit Name /PD7 /PD6 /PD5 /PD4 X /PD2 /PD1 /PD0

Power-On 1 1 1 1 U 1 1 1

/RESET and WDT 1 1 1 1 U 1 1 1

Wake-Up from Pin Change P P P P U P P P

Bit Name OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0

Power-On 0 0 0 0 0 0 0 0

/RESET and WDT 0 0 0 0 0 0 0 0

Wake-Up from Pin Change P P P P P P P P

Bit Name /PH7 /PH6 /PH5 /PH4 /PH3 /PH2 /PH1 /PH0

Power-On 1 1 1 1 1 1 1 1

/RESET and WDT 1 1 1 1 1 1 1 1

Wake-Up from Pin Change P P P P P P P P

Bit Name WDTE EIS X ROC X X X X

Power-On 1 0 U 0 U U U U

/RESET and WDT 1 0 U 0 U U U U

Wake-Up from Pin Change 1 P U P U U U U

Bit Name X X X X X EXIE ICIE TCIE

Power-On U U U U U 0 0 0

/RESET and WDT U U U U U 0 0 0

Wake-Up from Pin Change U U U U U P P P

Bit Name - - - - - - - -

Power-On U U U U U U U U

/RESET and WDT P P P P P P P P

Wake-Up from Pin Change P P P P P P P P

X: Not used. U: Unknown or don’t care. P: Previous value before reset. t: Check Table 6

2. The Status of RST, T, and P of STATUS Register

A RESET condition is initiated by the following events:

1. A power-on condition,

2. A high-low-high pulse on /RESET pin, and

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3. Watchdog timer time-out.

The values of T and P, listed in Table 6 are used to check how the processor wakes up. Table 7 shows the events that may affect the status of T and P.

Table 6 The Values of RST, T and P after RESET

Reset Type T P

Power on 1 1 /RESET during Operating mode *P *P /RESET wake-up during SLEEP mode 1 0 WDT during Operating mode 0 *P WDT wake-up during SLEEP mode 0 0 Wake-Up on pin change during SLEEP mode 1 0

*P: Previous status before reset

Table 7 The Status of T and P Being Affected by Events.

Event T P

Power on 1 1 WDTC instruction 1 1 WDT time-out 0 *P SLEP instruction 1 0 Wake-Up on pin change during SLEEP mode 1 0

*P: Previous value before reset

VDD

D Q

Oscillator

Power-on

Reset

Voltage Detector

WDTE

CLK

CLR

CLK

/RESET

WDT

WDT Timeout

Setup Time

RESET

Fig. 9 Block Diagram of Controller Reset

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4.6 Interrupt

The EM78P156EL has three falling-edge interrupts listed below:

(1) TCC overflow interrupt (2) Port 6 Input Status Change Interrupt (3) External interrupt [(P60, /INT) pin].

Before the Port 6 Input Status Change Interrupt is enabled, reading Port 6 (e.g. "MOV R6,R6") is necessary. Each pin of Port 6 will have this feature if its status changed. Any pin configured as output or P60 pin configured as /INT is excluded from this function. The Port 6 Input Status Changed Interrupt can wake up the EM78P156EL from the sleep mode if Port 6 is enabled prior to going into the sleep mode by executing SLEP. When the chip wakes-up, the controller will continue to execute the succeeding address if the global interrupt is disabled or branch to the interrupt vector 008H if the global interrupt is enabled.

RF is the interrupt status register that records the interrupt requests in the relative flags/bits. IOCF is an interrupt mask register. The global interrupt is enabled by the ENI instruction and is disabled by the DISI instruction. When one of the interrupts (enabled) occurs, the next instruction will be fetched from address 008H. Once in the interrupt service routine, the source of an interrupt can be determined by polling the flag bits in RF. The interrupt flag bit must be cleared by instructions before leaving the interrupt service routine and before interrupts are enabled to avoid recursive interrupts.

The flag (except ICIF bit) in the Interrupt Status Register (RF) is set regardless of the status of its mask bit or the execution of ENI. Note that the outcome of RF will be the logic AND of RF and IOCF (refer to Fig. 10). The RETI instruction ends the interrupt routine and enables the global interrupt (the execution of ENI).

When an interrupt is generated by the INT instruction (enabled), the next instruction will be fetched from address 001H.

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/IRQn

VCC

CLK

EM78P156EL

OTP ROM

C L

RFRD

IRQn

IRQm

INT

ENI/DISI

/RESET

4.7 Oscillator

1. Oscillator Modes

The EM78P156EL can be operated in three different oscillator modes, such as External RC oscillator mode (ERC), High XTAL oscillator mode (HXT), and Low XTAL oscillator mode (LXT). User can select one of them by programming MS and HLF in the CODE option register. Table 8 depicts how

IOCF

Q _

CLK

C L

IOCFRD

RFWR

IOCFWR

Fig. 10 Interrupt Input Circuit

IOD

these three modes are defined.

The up-most limited operation frequency of crystal/resonator on the different VDDs is listed in Table

Table 8 Oscillator Modes Defined by MS and HLP

Mode MS HLF HLP

ERC(External RC oscillator mode) 0 *X *X HXT(High XTAL oscillator mode) 1 1 *X LXT(Low XTAL oscillator mode) 1 0 0

<Note> 1. X, Don’t care

2.The transient point of system frequency between HXT and LXY is around 400 KHz.

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Table 9 The Summary of Maximum Operating Speeds

Conditions VDD Fxt max.(MHz)

2.3 4.0

Two cycles with two clocks

2. Crystal Oscillator/Ceramic Resonators (XTAL)

EM78P156EL can be driven by an external clock signal through the OSCI pin as shown in Fig. 11 below.

3.0 8.0

5.0 20.0

OSCI

OSCO

EM78P156EL

Fig. 11 Circuit for External Clock Input

In the most applications, pin OSCI and pin OSCO can connected with a crystal or ceramic resonator to generate oscillation. Fig. 12 depicts such circuit. The same thing applies whether it is in the HXT mode or in the LXT mode. Table 10 provides the recommended values of C1 and C2. Since each resonator has its own attribute, user should refer to its specification for appropriate values of C1 and C2. RS, a serial resistor, may be necessary for AT strip cut crystal or low frequency mode.

Ext. Clock

OSCI

EM78P156EL

OSCO

Fig. 12 Circuit for Crystal/Resonator

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XTAL

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EM78P156EL

Table 10 Capacitor Selection Guide for Crystal Oscillator or Ceramic Resonator

Oscillator Type Frequency Mode Frequency C1(pF) C2(pF)

455 kHz 100~150 100~150

Ceramic Resonators HXT

LXT

Crystal Oscillator

HXT

2.0 MHz 20~40 20~40

4.0 MHz 10~30 10~30

32.768kHz 25 15 100KHz 25 25 200KHz 25 25

455KHz 20~40 20~150

1.0MHz 15~30 15~30

2.0MHz 15 15

4.0MHz 15 15

OTP ROM

EM78P156EL

330 330

OSCI

Fig. 13 Circuit for Crystal/Resonator-Series Mode

OSCI

7404

XTAL

4.7K

7404

10K

7404

10K

Vdd

XTAL

Fig. 14 Circuit for Crystal/Resonator-Parallel Mode

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3. External RC Oscillator Mode

For some applications that do not need a very precise timing calculation, the RC oscillator (Fig. 15) offers a lot of cost savings. Nevertheless, it should be noted that the frequency of the RC oscillator is influenced by the supply voltage, the values of the resistor (Rext), the capacitor (Cext), and even by the operation temperature. Moreover, the frequency also changes slightly from one chip to another due to the manufacturing process variation.

In order to maintain a stable system frequency, the values of the Cext should not be less than 20pF, and that the value of Rext should not be greater than 1 M ohm. If they cannot be kept in this range, the frequency is easily affected by noise, humidity, and leakage.

The smaller the Rext in the RC oscillator, the faster its frequency will be. On the contrary, for very low Rext values, for instance, 1 KΩ, the oscillator becomes unstable because the NMOS cannot

discharge the current of the capacitance correctly.

Based on the above reasons, it must be kept in mind that all of the supply voltage, the operation temperature, the components of the RC oscillator, the package types, the way the PCB is layout, will affect the system frequency.

OSCI

EM78P156EL

Vcc

Rext

Cext

Fig. 15 Circuit for External RC Oscillator Mode

Table 11 RC Oscillator Frequencies

Cext Rext

20 pF

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3.3k 3.92 MHz 3.65 MHz

5.1k 2.67 MHz 2.60 MHz 10k 1.39MHz 1.40 MHz

100k 149 KHz 156 KHz

Average Fosc 5V,25°C Average Fosc 3V,25°C

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EM78P156EL

OTP ROM

3.3k 1.39 MHz 1.33 MHz

100 pF

300 pF

<Note> 1. Measured on DIP packages.

2. For design reference only.

4.8 CODE Option Register

The EM78P156EL has a CODE option word that is not a part of the normal program memory. The

5.1k 940 KHz 920 KHz 10k 480 KHz 475 KHz

100k 52 KHz 50 KHz

3.3k 595 KHz 560 KHz

5.1k 400 KHz 390 KHz 10k 200 KHz 200 KHz

100k 21 KHz 20 KHz

option bits cannot be accessed during normal program execution.

Code Option Register and Customer ID Register arrangement distribution:

Word 0 Word 1

Bit12~Bit0 Bit12~Bit0

1. Code Option Register (Word 0)

WORD 0

Bit12 Bit11 Bit10 Bit9 Bit8 Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

MS /ENWDT CLK CS HLF - HLP - - - - - -

• Bit 12 (MS):Oscillator type selection. 0: RC type 1: XTAL type (XTAL1 and XTAL2)

• Bit 11 (/ENWDT): Watchdog timer enable bit. 0: Enable 1: Disable

• Bit 10 (CLK): Instruction period option bit. 0: two oscillator periods. 1: four oscillator periods. Refer to the section on Instruction Set.

• Bit 9 (CS): Code Security Bit 0: Security On 1: Security Off

• Bit 8 (HLF): XTAL frequency selection 0: XTAL2 type (low frequency, 32.768KHz)

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1: XTAL1 type (high frequency) This bit will affect system oscillation only when Bit12 (MS) is “1”. When MS is”0”, HLF must be “0”. <Note>: The transient point of system frequency between HXT and LXY is around 400 KHz.

• Bit 7: Reserved. The bit set to “1” all the time.

• Bit 6 (HLP): Power selection. 0: Low power 1: High power

• Bit 5~0 : Customer’s ID code

2. Customer ID Register (Word 1)

Bit 12~Bit 0

XXXXXXXXXXXXX

• Bit 12~0: Customer’s ID code

4.9 Power On Considerations

Any microcontroller is not guaranteed to start to operate properly before the power supply stays at its steady state. EM78P156EL is equipped with Power On Voltage Detector (POVD) with a detecting level of 1.8V. It will work well if Vdd rise quick enough (50 ms or less). In many critical applications, however, extra devices are still required to assist in solving power-up problems.

4.10 External Power On Reset Circuit

The circuit shown in Fig.16 implements an external RC to produce the reset pulse. The pulse width (time constant) should be kept long enough for Vdd to reached minimum operation voltage. This circuit is used when the power supply has slow rise time. Because the current leakage from the /RESET pin is about ±5µA, it is recommended that R should not be greater than 40 K. In this way, the /RESET pin voltage is held below 0.2V. The diode (D) acts as a short circuit at the moment of power down. The capacitor C will discharge rapidly and fully. Rin, the current-limited resistor, will prevent high current or ESD (electrostatic discharge) from flowing to pin /RESET.

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Vdd

/RESET

EM78P156EL

Fig. 16 External Power-Up Reset Circuit

4.11 Residue-Voltage Protection

When battery is replaced, device power (Vdd) is taken off but residue-voltage remains. The residue-voltage may trips below Vdd minimum, but not to zero. This condition may cause a poor power on reset. Fig.18 and Fig. 19 show how to build a residue-voltage protection circuit.

Rin

Vdd

EM78P156EL

/RESET

Fig. 17 Circuit 1 for the Residue Voltage Protection

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40K

Vdd

33K

10K

1N4684

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EM78P156EL

OTP ROM

EM78P156EL

4.12 Instruction Set

Each instruction in the instruction set is a 13-bit word divided into an OP code and one or more operands. Normally, all instructions are executed within one single instruction cycle (one instruction consists of 2 oscillator periods), unless the program counter is changed by instruction "MOV R2,A",

Vdd

/RESET

40K

Fig. 18 Circuit 2 for the Residue Voltage Protection

Vdd

"ADD R2,A", or by instructions of arithmetic or logic operation on R2 (e.g. "SUB R2,A", "BS(C) R2,6", "CLR R2", ⋅⋅⋅⋅). In this case, the execution takes two instruction cycles.

If for some reasons, the specification of the instruction cycle is not suitable for certain applications, try modifying the instruction as follows:

(A) Change one instruction cycle to consist of 4 oscillator periods. (B) "JMP", "CALL", "RET", "RETL", "RETI", or the conditional skip ("JBS", "JBC", "JZ", "JZA", "DJZ",

"DJZA") commands which were tested to be true, are executed within two instruction cycles. The instructions that are written to the program counter also take two instruction cycles.

Case (A) is selected by the CODE Option bit, called CLK. One instruction cycle consists of two oscillator clocks if CLK is low, and four oscillator clocks if CLK is high.

Note that once the 4 oscillator periods within one instruction cycle is selected as in Case (A), the internal clock source to TCC should be CLK=Fosc/4, instead of Fosc/ 2 as indicated in Fig. 5.

In addition, the instruction set has the following features:

(1) Every bit of any register can be set, cleared, or tested directly.

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(2) The I/O register can be regarded as general register. That is, the same instruction can operate

on I/O register.

The symbol "R" represents a register designator that specifies which one of the registers (including operational registers and general purpose registers) is to be utilized by the instruction. "b" represents a bit field designator that selects the value for the bit which is located in the register "R", and affects operation. "k" represents an 8 or 10-bit constant or literal value.

INSTRUCTION BINARY HEX MNEMONIC OPERATION STATUS AFFECTED

0 0000 0000 0000 0000 NOP No Operation None 0 0000 0000 0001 0001 DAA Decimal Adjust A C

0 0000 0000 0010 0002 CONTW 0 0000 0000 0011 0003 SLEP 0 0000 0000 0100 0004 WDTC 0 0000 0000 rrrr 000r IOW R

0 0000 0001 0000 0010 ENI Enable Interrupt None 0 0000 0001 0001 0011 DISI Disable Interrupt None 0 0000 0001 0010 0012 RET

0 0000 0001 0011 0013 RETI 0 0000 0001 0100 0014 CONTR

0 0000 0001 rrrr 001r IOR R 0 0000 01rr rrrr 00rr MOV R,A 0 0000 1000 0000 0080 CLRA 0 0000 11rr rrrr 00rr CLR R 0 0001 00rr rrrr 01rr SUB A,R 0 0001 01rr rrrr 01rr SUB R,A 0 0001 10rr rrrr 01rr DECA R 0 0001 11rr rrrr 01rr DEC R 0 0010 00rr rrrr 02rr OR A,R 0 0010 01rr rrrr 02rr OR R,A 0 0010 10rr rrrr 02rr AND A,R 0 0010 11rr rrrr 02rr AND R,A 0 0011 00rr rrrr 03rr XOR A,R 0 0011 01rr rrrr 03rr XOR R,A 0 0011 10rr rrrr 03rr ADD A,R 0 0011 11rr rrrr 03rr ADD R,A 0 0100 00rr rrrr 04rr MOV A,R 0 0100 01rr rrrr 04rr MOV R,R 0 0100 10rr rrrr 04rr COMA R 0 0100 11rr rrrr 04rr COM R 0 0101 00rr rrrr 05rr INCA R 0 0101 01rr rrrr 05rr INC R 0 0101 10rr rrrr 05rr DJZA R 0 0101 11rr rrrr 05rr DJZ R

0 0110 00rr rrrr 06rr RRCA R

0 0110 01rr rrrr 06rr RRC R

0 0110 10rr rrrr 06rr RLCA R 0 0110 11rr rrrr 06rr RLC R

[Top of Stack] → PC, Enable

A → CONT

0 → WDT, Stop oscillator

0 → WDT

A → IOCR

[Top of Stack] → PC

Interrupt CONT → A IOCR → A

A → R

0 → A

0 → R

R-A → A

R-A → R

R-1 → A

R-1 → R A ∨ R → A A ∨ R → R A & R → A A & R → R A ⊕ R → A A ⊕ R → R A + R → A A + R → R

R → A

R → R /R → A /R → R

R+1 → A R+1 → R

R-1 → A, skip if zero

R-1 → R, skip if zero

R(n) → A(n-1),

R(0) → C, C → A(7)

R(n) → R(n-1),

R(0) → C, C → R(7)

R(n) → A(n+1),

R(7) → C, C → A(0)

R(n) → R(n+1),

None

T,P T,P

None <Note1>

None None None

None <Note1>

None

Z Z,C,DC Z,C,DC

None None

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R(7) → C, C → R(0) 0 0111 00rr rrrr 07rr SWAPA R 0 0111 01rr rrrr 07rr SWAP R

0 0111 10rr rrrr 07rr JZA R 0 0111 11rr rrrr 07rr JZ R 0 100b bbrr rrrr 0xxx BC R,b 0 101b bbrr rrrr 0xxx BS R,b 0 110b bbrr rrrr 0xxx JBC R,b if R(b)=0, skip None

0 111b bbrr rrrr 0xxx JBS R,b if R(b)=1, skip None 1 00kk kkkk kkkk 1kkk CALL k 1 01kk kkkk kkkk 1kkk JMP k

1 1000 kkkk kkkk 18kk MOV A,k 1 1001 kkkk kkkk 19kk OR A,k 1 1010 kkkk kkkk 1Akk AND A,k 1 1011 kkkk kkkk 1Bkk XOR A,k

1 1100 kkkk kkkk 1Ckk RETL k 1 1101 kkkk kkkk 1Dkk SUB A,k 1 1110 0000 0001 1E01 INT 1 1111 kkkk kkkk 1Fkk ADD A,k

<Note 1> This instruction is applicable to IOC5~IOC6, IOCB~IOCF only.

R(0-3) → A(4-7),

R(4-7) → A(0-3) R(0-3) ↔ R(4-7)

R+1 → A, skip if zero

R+1 → R, skip if zero

0 → R(b) 1 → R(b)

PC+1 → [SP],

(Page, k) → PC (Page, k) → PC

k → A A ∨ k → A A & k → A A ⊕ k → A

k → A,

[Top of Stack] → PC

k-A → A

PC+1 → [SP],

001H → PC

k+A → A

None None

None

None None <Note2> None <Note3>

None

Z Z Z

None

Z,C,DC

None

Z,C,DC

<Note 2> This instruction is not recommended for RF operation. <Note 3> This instruction cannot operate under RF.

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EM78P156EL

4.13 Timing Diagrams

AC Test Input/Output Waveform

2.4

2.0

TEST POINTS

0.8

0.4

AC Testing : Input is driven at 2.4V for logic "1",and 0.4V for logic "0".Timing measurements are

made at 2.0V for logic "1",and 0.8V for logic "0".

2.0

0.8

OTP ROM

RESET Timing (CLK="0")

CLK

/RESET

TCC Input Timing (CLKS="0")

Tins

CLK

Tdrh

NOP

Instruction 1

Executed

TCC

Ttcc

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5. ABSOLUTE MAXIMUNM RATINGS

Items Rating Temperature under bias 0°C to 70°C Storage temperature -65°C to 150°C Input voltage -0.3V to +6.0V Output voltage -0.3V to +6.0V

EM78P156EL

OTP ROM

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OTP ROM

6. ELECTRICAL CHARACTERISTICS

6.1 DC Electrical Characteristic

( Ta= 0°C ~ 70 °C, VDD= 5.0V±5%, VSS= 0V )

Symbol Parameter Condition Min Typ. Max Unit

FXT

ERC ERC: VDD to 5V

IIL Input Leakage Current for input pins VIN = VDD, VSS

VIH1 Input High Voltage (VDD=5V) Ports 5, 6 2.0 V

VIL1 Input Low Voltage (VDD=5V) Ports 5, 6 0.8 V

VIHT1 Input High Threshold Voltage (VDD=5V)

VILT1 Input Low Threshold Voltage (VDD=5V) /RESET, TCC 0.8 V

VIHX1 Clock Input High Voltage (VDD=5V) OSCI 3.5 V

VILX1 Clock Input Low Voltage (VDD=5V) OSCI 1.5 V

VIH2 Input High Voltage (VDD=3V) Ports 5, 6 1.5 V

VIL2 Input Low Voltage (VDD=3V) Ports 5, 6 0.4 V

VIHT2 Input High Threshold Voltage (VDD=3V)

VILT2 Input Low Threshold Voltage (VDD=3V) /RESET, TCC 0.4 V

VIHX2 Clock Input High Voltage (VDD=3V) OSCI 2.1 V

VILX2 Clock Input Low Voltage (VDD=3V) OSCI 0.9 V

VOH1

VOL1 Output Low Voltage (P60~P61) IOL = 12.0 mA 0.4 V VOL2

IPH Pull-high current Pull-high active, input pin at VSS -50 -70 -240 IPD Pull-down current Pull-down active, input pin at VDD 25 50 120

ISB

ICC1

ICC2

ICC3

ICC4

XTAL: VDD to 3V Two cycle with two clocks DC 8.0 MHz XTAL: VDD to 5V Two cycle with two clocks DC 20.0 MHz

Output High Voltage

(Ports 5, 6)

Output Low Voltage

(Port5, P62~P67)

Power down current Power down current

Operating supply current

(VDD=3V) at two cycles/four clocks Operating supply current

(VDD=5.0V)

at two cycles/two clocks

Operating supply current

(VDD=5.0V)

at two cycles/four clocks

R: 5.1KΩ, C: 100 pF F±30%

/RESET, TCC 2.0 V

/RESET, TCC 1.5 V

IOH = -12.0 mA 2.4 V

IOL = 10.5 mA 0.4 V

All input and I/O pins at VDD,

output pin floating, WDT disabled

All input and I/O pins at VDD,

output pin floating, WDT enabled

/RESET= 'High', Fosc=32KHz

(Crystal type,CLKS="0"), output

pin floating, WDT disabled

/RESET= 'High', Fosc=32KHz

(Crystal type,CLKS="0"), output

pin floating, WDT enabled

/RESET= 'High', Fosc=4MHz

(Crystal type, CLKS="0"), output

pin floating, WDT enabled

/RESET= 'High', Fosc=10MHz

(Crystal type, CLKS="0"), output

pin floating, WDT enabled

1 10

15 15 30 µA

20 35 µA

1.6 mA

4.0 mA

940

F±30%

±1 µA

KHz

µA µA

This specification is subject to change without prior notice. 2002/04/19 37

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EM78P156EL

OTP ROM

6.2 AC Electrical Characteristic

(Ta=0°C ~ 70 °C, VDD=5V±5%, VSS=0V)

Symbol Parameter Conditions Min Typ Max Unit

Dclk Input CLK duty cycle 45 50 55 % Tins Ttcc TCC input period (Tins+20)/N* ns

Tdrh Device reset hold time

Trst /RESET pulse width

Twdt Watchdog timer period Tset Input pin setup time 0 ns

Thold Input pin hold time 20 ns

Tdelay Output pin delay time Cload=20pF 50 ns

Instruction cycle time

(CLKS="0")

* N= selected prescaler ratio.

Crystal type 100 DC ns

RC type 500 DC ns

Ta = 25°C Ta = 25°C Ta = 25°C

16 16.8 17.6 ms

2000 ns

16 16.8 17.6 ms

This specification is subject to change without prior notice. 2002/04/19 38

Page 39

APPENDIX

Package Types:

OTP MCU Package Type Pin Count Package Size

EM78P156ELP DIP 18 300 mil EM78P156ELM SOP 18 300 mil

EM78P156ELAS SSOP 20 209 mil

EM78P156ELKM SSOP 20 209 mil

EM78P156EL

OTP ROM

This specification is subject to change without prior notice. 2002/04/19 39

Datasheet EM78P156ELP, EM78P156ELM, EM78P156ELKM, EM78P156ELAS Datasheet (ELAN)

Specifications and Main Features

Frequently Asked Questions

User Manual