D8251 EQU 0FFE0H ZXK EQU 0FFDCH ZWK EQU 0FFDDH
CODE SEGMENT
ASSUME CS:CODE,DS:CODE,ES:CODE ORG 35C0H ;TX=RX ;===修改开始 START: MOV DX,Z8251 MOV AL,00H OUT DX,AL MOV AL,00H OUT DX,AL MOV AL,00H OUT DX,AL MOV AL,40H OUT DX,AL MOV AL,0CEH OUT DX,AL MOV AL,25H OUT DX,AL ;===修改结束
MOV AL,01H MOV BX,0400H MOV [BX],AL SR0: CALL WP MOV SI,4000H MOV DI,5000H MOV CX,0010H SR1: MOV AH,[SI] CALL SEND CALL RX MOV [DI],AH INC SI INC DI LOOP SR1 SR2: CALL DIS JMP SR2 RX: MOV DX,Z8251 RX1: IN AL,DX TEST AL,02H JZ RX1 MOV DX,D8251 IN AL,DX
MOV AH,AL RET
;------------------------ WP: MOV BUF,11H MOV BUF+1,10H MOV BUF+2,10H MOV BUF+3,10H MOV BUF+4,10H MOV BUF+5,10H RET
;-------------------------- SEND: MOV DX,Z8251 W1: IN AL,DX TEST AL,01H JZ W1 MOV DX,D8251 MOV AL,AH OUT DX,AL RET
;--------------------------- DIS: MOV CL,20H MOV BX,OFFSET BUF
DIS1: MOV AL,[BX] PUSH BX
MOV BX,OFFSET LED XLAT POP BX MOV DX,ZXK OUT DX,AL MOV AL,CL MOV DX,ZWK OUT DX,AL PUSH CX MOV CX,0100H DELAY: LOOP $ POP CX CMP CL,01H JZ EXIT INC BX SHR CL,1 JMP DIS1 EXIT: MOV AL,00H MOV DX,ZWK OUT DX,AL
RET
;--------------------------
LED DB 0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H DB 88H,83H,0C6H,0A1H,86H,8EH,0FFH,0CH,0DEH,0F3H BUF DB
;-------------------------- CODE ENDS END START
