sh66p31b SinoWealth Micro-Electronics Corp. Ltd, sh66p31b Datasheet - Page 11

• Manufacturer Part Number: sh66p31b
• Description: Otp 1k 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 Block Diagram
Port Interrupt PROGRAMMING NOTES：
If user wants to generate an interrupt when a falling edge from V
executed.
1. Set the port as input port, fill port data register with “1”.
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 can 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
.
Edge Detector
Edge Detector
Falling
11
Falling
DD
to GND emerges on the port, the following must be
IEP
IRQP
IEP
opt_pint = 0 (Default)
IRQP
opt_pint = 1
Port Interrupt
Port Interrupt
SH66P31B
DD
.