1996 Nov 25

7

Philips Semiconductors

Product specification

PCF84C00

Note

1. The interrupt signal must remain active until the vector address (05 H) is present on the address bus.

RESET

44

I/O

reset input: used to initialize the microcontroller (active HIGH); also output of

power-on-reset circuit

P1.0 to P1.3

45 to 48

I/O

4 bits of Port 1: 8-bit quasi-bidirectional I/O port

EXDI

49

I

External derivative interrupt (active LOW): EXDI is ‘OR-ed’ with the internal

serial interrupt and can be used to initiate an interrupt from external hardware

emulating derivative functions. EXDI is pulled HIGH internally. The derivative

interrupt is polled during time slot TS6 (note 1), and is only accepted if an EN

SI instruction has been executed and the device is not already executing an

interrupt routine. Derivative interrupts are not latched in the PCF84C00.

P1.4 to P1.7

50 to 53

I/O

4 bits of Port 1: 8-bit quasi-bidirectional I/O port

P2.0 to P2.1

54, 55

I/O

2 bits of Port 2: 4-bit quasi-bidirectional I/O port

56

P

power supply: 2.5 V to 5.5 V

SYMBOL

PIN

TYPE

DESCRIPTION