t4-1.asm

上课时老师讲的一些经典的例子；错过了就太可惜了呀

DSEG SEGMENT
BUFF DB 4 DUP (0)
     DB 'H',0DH,0AH,'$'
DSEG ENDS
;
CSEG SEGMENT
     ASSUME CS:CSEG,DS:DSEG
START:
     MOV AX,DSEG
     MOV DS,AX
     MOV AX,0F000H
     MOV ES,AX
     MOV DX,ES:[0]
     MOV BX,OFFSET BUFF
     CALL HTASCS
;
     MOV DX,OFFSET BUFF
     MOV AH,9
     INT 21H
;
     MOV AX,4C00H
     INT 21H
;
HTASCS PROC
         MOV CX,4
HTASCS1: ROL DX,1
         ROL DX,1
         ROL DX,1
         ROL DX,1
         MOV AL,DL
         CALL HTOASC
         MOV [BX],AL
         INC BX
         LOOP HTASCS1
         RET
HTASCS ENDP
;
HTOASC	PROC  NEAR
        AND  AL,0FH
        CMP  AL,9
        JBE  HTOASC1
        ADD  AL,37H
HTOASC2:RET
HTOASC1:ADD  AL,30H
        JMP  HTOASC2
HTOASC  ENDP
CSEG    ENDS
        END START