Songhan MCU external interrupt program

 chip sn8f27e65
//{{SONIX_CODE_OPTION
//Full source code download: http://www.51hei.com/f/shwbzd.rar
 .Code_Option WDT_CLK Flosc/4
 .Code_Option Reset_Pin P04
 .Code_Option LVD LVD_Max ; 3.3V Reset
 .Code_Option Watch_Dog Disable ;Turn off watchdog.Code_Option
 Low_Fcpu Flosc/1
 .Code_Option High_Clk IHRC_16M ; Internal 16M RC Oscillator
 .Code_Option High_Fcpu Fhosc/1
 .Code_Option Security Enable
 .Code_Option Noise_Filter Enable
//}}SONIX_CODE_OPTION
.DATA;Data
 ORG 0
 TEMP DS 1
 ACCBUF DS 1
 PflagBUF DS 1
 K DS 1
.CONST
 K1 EQU K.0; Flag bit
.CODE; Program code
 
 ORG 0000H
 JMP A1
 ORG 09H; External interrupt entry
 JMP INT00
A1: MOV A, #02H; Set the interrupt trigger mode to low level trigger
 B0MOV PEDGE, A
 B0BCLR FP00IRQ ; Clear interrupt flag
 B0BSET FP00IEN; Enable interrupt
 B0BSET FGIE; Enable general interrupt
 B0BSET K1; Set flag
 JMP $
; ****************************** **********************
;Interrupt service routine
; ************************** **************************
INT00:
 B0BCLR FP00IEN; disable interrupt
 B0BCLR FGIE; disable interrupt
 B0XCH A,ACCBUF; push stack
 B0MOV A,PFLAG;
 B0MOV PFLAGBUF,A;
 B0BTS1 FP00IRQ; Determine whether an interrupt
 JMP actually occurs INT01
 
 B0BTS1 K1; judge the flag to control the LED status flag is 1 LED is on
 JMP K01
 B0BCLR K1; clear the flag to 0
 B0BSET P0M.3; set P0.3 to output mode
 B0BCLR P0.3; turn on the LED
;******** ************************************
;Key debounce
;********* **********************************
K00: CALL M001; Delay
 B0BCLR P0M.0; Set P0.0 Input mode
 B0BSET P0UR.0; Set P0.0 to pull up
 B0BTS1 P0.0; Determine whether P0.0 is 0 to continue or not to skip the next instruction  
 JMP K00
 
 CALL M001
 B0BCLR P0M.0
 B0BSET P0UR.0
 B0BTS1 P0.0 ; Determine whether P0.0 is 0 and whether to continue or skip the next instruction  
 JMP K00
 JMP INT01
K01:
 B0BTS0 K1
 JMP INT01
 B0BSET K1
 B0BSET P0M.3
 B0BSET P0.3
K02:
 CALL M001
 B0BCLR P0M.0
 B0BSET P0UR.0
 B0BTS1 P0.0; Determine whether P4.0 is 1 and whether to continue or skip the next instruction  
 JMP K02
 CALL M001
 B0BCLR P0M.0
 B0BSET P0UR.0
 B0BTS1 P0.0; Check if P4.0 is 1, whether to continue or not, skip the next instruction  
 JMP K02
INT01:
 B0MOV A,PFLAGBUF; Pop stack
 B0MOV PFLAG,A
 B0XCH A,ACCBUF
 B0BCLR FP00IRQ
 B0BSET FP00IEN
 B0BSET FGIE
 RETI
;*************************************************
; Delay subroutine
;****************************************************
M001: MOV A,#200
 MOV 50H,A
M002: MOV A,#250
 MOV 51H,A
M003: DECMS 51H
 JMP M003
 DECMS 50H
 JMP M002
 RET
 ENDP