jiekou.asm

单片机与FPGA通信的小程序

org 0000h
ljmp MAIN
org 001bh
ljmp T1INT

MAIN:MOV TMOD,#10H
     MOV TH1,#0FCH
     MOV TL1,#018H  ;记数初始化1MS
     SETB EA
     SETB ET1
     SETB EX0
     SETB TR1       ;开中断
     MOV 78H,#0
     MOV 79H,#0
     MOV 7AH,#0
     MOV 7BH,#0
     MOV 7CH,#0
     MOV 7DH,#0
     MOV 7EH,#0
     MOV 7FH,#0
     MOV 40H,#250   ;设置中断次数  250MS
TT:  LJMP TT
     
T1INT:MOV TH1,#0FCH
      MOV TL1,#018H
      MOV A,P0
      ANL A,#0FH
      JB  P2.7,M
      MOV 78H,A
      CJNE A,#10,NEXT
      INC 79H
      SJMP NEXT
M:    MOV 7AH,A
NEXT: DJNZ 40H,TT1
DSP:  LCALL DISPLAY
      MOV  40H,#250
TT1:  RETI

DISPLAY:
        SETB RS0
        PUSH ACC
        PUSH DPH
        PUSH DPL
        MOV R7,#08H        ;显示8位
        MOV R0,#7FH        ;显示缓冲区最高位地址7FH
DIR0:   MOV A,@R0
        MOV DPTR,#TAB
        MOVC A,@A+DPTR
        MOV SBUF,A
DIR1:   JNB TI,DIR1
        CLR TI
        DEC R0
        DJNZ R7,DIR0
        CLR RS0
        POP DPL
        POP DPH
        POP ACC
        RET
TAB:    DB 0FCH,60H,0DAH,0F2H,66H,0B6H,0BEH
        DB 0E0H,0FEH,0F6H,77H,3EH,9CH,7AH,9EH,8EH