sh66k31c SinoWealth Micro-Electronics Corp. Ltd, sh66k31c Datasheet - Page 11

• Manufacturer Part Number: sh66k31c
• Description: Mask 4-bit Micro-controller
• Manufacturer: SinoWealth Micro-Electronics Corp. Ltd

Port Interrupt
When opt_pint is “0” (Default), PORTB.0 - 3, PORTC.0 - 3 are used as port interrupt sources. When opt_pint is “1”, PORTA.1 -
3,PORTB.0 - 3 and PORTC.0 are used as port interrupt sources. Since PORT I/O is a bit programmable I/O, only the transitions
from V
request until all of the pins return to V
Port interrupt PROGRAMMING NOTES：
If the user wants to generate an interrupt when a falling edge from V
1. Set the port as input port, fill in the port data register with “1” and avoid port floating.
2. Pull-high the port (Use external pull-high resistance or set PULLEN to “1”).
3. Set corresponding IEP to “1” and clear IRQP to “0”
And further falling edge transition would not be able to make interrupt request until all of the pins return to V
DD
to GND will generate an interrupt request. Thus, further falling edge transitions will not be able to make interrupt
PB.n
PC.n
PA.n
PC.0
PB.x
Note: n=0, 1, 2, 3
PBCR.n
PCCR.n
PACR.n
PCCR.0
PBCR.x
Note: n = 1, 2, 3
x = 0, 1, 2, 3
DD
PORT Interrupt Block Diagram.
Edge Detector
Edge Detector
Falling
11
Falling
DD
to GND emerges on the port, the following must be executed.
IEP
IRQP
IEP
opt_pint = 0 (Default)
IRQP
opt_pint = 1
Port Interrupt
Port Interrupt
SH66K31C
DD