Displaying Time in Assembly

Question

Hello im trying to display the actual time hours/minutes/seconds this is my code sample:

MOV AH, 2Ch
INT 21h

MOV AH, 0Eh

MOV AL, CH
INT 10h

MOV AL, 3Ah
IN         


        

Answer 1

You need a print routine to print bytes as numbers, instead of writing them directly to the screen as characters. Luckily since you only have to deal with values between 0 and 59, and since you want leading zeroes, the problem is pretty simple. Assuming value to be printed in AX:

print2Digits:
    ;; input in AX (0-99)
    ;; clobbers AX and DX, save them if needed
    MOV   DL, 0Ah ; divide by: 10
    DIV   DL      ; first digit in AL (quotient), second digit in AH (remainder)
    MOV   DX, AX  ; save the digits
    ADD   AL, 30h ; ASCII '0'
    MOV   AH, 0Eh ; set up print
    INT   10h     ; print first digit.
    MOV   AL, DH  ; retrieve second digit
    ADD   AL, 30h
    INT   10h     ; print it
    RET