Converting my solution from decimal to Hex

Question

My goal is to display the solution of 2 numbers entered by the user in Hexadecimal. As of right now my code gets 2 numbers from the user, then returns the solution in decimal. What i think i should do is just to get my decimal solution and convert it into Hexadecimal after the numbers have been added together. If there is another plausible way please let me know. Thanks You.

org $8000
START   movea.l #MSG1, A1
    move.b  #13,D0
    trap    #15        
    clr.w   D2
    JSR Loop

    move.w  d2, d4
    movea.l #msg2, a1
    move.b  #13,D0
    trap    #15       
    clr.w   d2
    jsr loop

    movea.l #msg3, A1
    move.b  #13,D0
    trap    #15 
    add.w   d4, d2
    JSR DISP

    MOVE.B  #9,D0
    TRAP    #15      
LOOP    move.b  #5,D0
    trap    #15
    cmp.b   #$0D, D1
    BEQ BREAK
    and.b   #$0F, d1
    mulu    #10, d2
    add.w   d1, d2
    jmp loop
Break   rts
DISP    clr.b   d3
DISDIV  divu    #10, D2
    move.b  #16, d5
    ror.l   d5, d2
    or.b    #$30, d2
    move.b  d2, -(A7)
    addq    #1, d3
    clr.w   d2
    ror.l   d5, d2
    bne DISDIV
DISDIG  move.b  (a7)+, D1
    move.b  #6,D0
    trap    #15     ; char out
    subq.b  #1, D3
    bne DISDIG
    rts
    org $8100
MSG1    DC.B    'Please enter a two digit number ', 0
MSG2    DC.B    'Please enter another two digit number ', 0
MSG3    DC.B    'The sum of the two 2 digit numbers you entered is ', 0
    end     start

I am using the EASY68k Assembler.

Wow, I haven't seen 68K assembler in ages. It was always my favorite. — Mark Ransom, Jul 25 '12 at 02:26
Haha, yea i actually didnt even know what site to post this question on. — The Tokenizer, Jul 26 '12 at 01:47

score 3 · Accepted Answer · answered Jul 25 '12 at 02:25

You need to change both the input and output code.

The input code ANDs the character with $0f, which works when the character is 0-9 but not when the character is a-f. You'll need to test the character and treat it differently for the a-f case. Then you'll need to multiply the prior result by 16 instead of 10.

You have the opposite problem on output. Changing the divu from 10 to 16 gets you halfway there, but where you add $30 to convert to ASCII 0-9 you'll need to test the value and add $41 instead if it's between 10 and 15.

I did notice that mark, and i was working on it. you gave me a nice outline of what i need to do, so im going to try and follow right now. — The Tokenizer, Jul 25 '12 at 03:27

score 1 · Answer 2 · answered Jul 25 '12 at 02:13

1

Just change

DISDIV  divu    #10, D2

to

DISDIV  divu    #16, D2

answered Jul 25 '12 at 02:13

Doug Currie

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@TheObliviator, not so fast - this answer is incomplete. Did you even test it? – Mark Ransom Jul 25 '12 at 02:25

Converting my solution from decimal to Hex

2 Answers2