B3-2

EM78P156E

Symbol

I/O

Function

OSCI

I

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

* ERC type: RC oscillator input pin.

* IRC type: 50K ohm pulled high for 4MHz.

OSCO

I/O

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

* RC type: Instruction clock ouput.

* External clock signal input.

TCC

I

* Real time clock/counter with Schmitt trigger input pin, must be tied to V

DD

or V

V.

PIN DESCRIPTION

Table 1 Pin description-EM78P156E

WDT Timer

IOC5

R5

Instruction

Decoder

ROM

Interrupt

Controller

R1(TCC)

Oscillator/Timing

Control

Prescaler

RAM

R4

Instruction

register

R2

Stack

OSCI

OSCO

/RESET

DATA & CONTROL BUS

TCC

/INT

ACC

R3

ALU

WDT

Time-out

IOCA

Internal C

External R

oscillator

Sleep

& Wake

Control

P

5

0

P

5

2

P

5

3

P

5

1

IOC6

R6

P

6

0

P

6

2

P

6

3

P

6

1

P

6

4

P

6

6

P

6

7

P

6

5

IV.

FUNCTIONAL BLOCK DIAGRAM

III.

PIN ASSIGNMENTS

DIP

SOP

SOIC

1

2

3

4

5

6

7

8

9

18

17

16

15

14

13

12

11

10

P52

P53

TCC

RESET

P60,INT

P61

P62

P63

P51

P50

OSCI

OSCO

P67

P66

P65

P64

EM78P156E

Fig. 1 Pin assignments

Fig. 2 Functional block diagram