;p=pic16c71,xt=40000hz

LISTP=16c71

;

ZEQU2

RBPUEQU7

TEMPEQU10H

OPTIONREGEQU1H

FEQU1

PORT_BEQU06H

;

INCLUDE<P16c71.INC>

LIST

;

ORG0；复位地址

GOTOSTART

;

ORG4；中断向量

GOTOSERVICEINTERRUPT

;

START

CALLINITPORT_B；初始化B口

LOOP

SLEEP；省电睡眠，等待被唤醒

NOP

GOTOLOOP

;

SERVICEINTERRUPT

BTFSCINTCON,RBIF

GOTOSERVICEWAKUP

CLRFINTCON

BSFINTCON,RBIE

RETFIE

;

;检查是哪个键被按下，并点亮相应的LED直到按键释放，再返回睡眠状态

;

SERVICEWAKUP

BCFINTCON,RBIE

COMFPORT_B,W

BCFINTCON,RBIF

CALLDELAY16

COMFPORT_B,W

ANDLWB'11110000'

MOVWFTEMP

SWAPFTEMP,W

MOVWFPORT_B

CALLKEYRELEASE

RETFIE

;

;等待所有的按键都被释放程序

;

KEYRELEASE

CALLDELAY16

COMFPORT_B,W

BCFINTCON,RBIF

BCFINTCON,RBIE

ANDLWB'11110000'

BTFSCSTATUS,Z

RETURN

GOTOKEYRELEASE

;

;初始化B口子程序

;

INITPORT_B

BSFSTATUS,RP0

MOVLWB'11110000'

MOVWFTRISB

BCFOPTIONREG,RBPU

BCFSTATUS,RP0

CLRFPORT_B

BCFINTCON,RBIE

MOVFPORT_B,W

BCFINTCON,RBIF

BSFINTCON,RBIE

BSFINTCON,GIE

RETURN

;

;延时去抖动子程序

DELAY16

BSFSTATUS,RP0

MOVLWB'00000111'

MOVWFOPTIONREG

BCFSTATUS,RP0

CLRFTMR0

BCFINTCON,T0IF

CHECKAGAIN

BTFSSINTCON,T0IF

GOTOCHECKAGAIN

BCFINTCON,T0IF

RETURN

END