org $400
move.l #$FFF0,sp set the stack pointer

move.l #12,d0 switch off echo
move.l #0,d1
trap #15

loop move.b #5,d0 read one character into D1
trap #15

move.b #6,d0 echo it to the screen
trap #15

bra loop and repeat

end $400
wrote above program! I need to declare a String "123456abcdef"

Then calculate there code in ASCII now im stuck where i am! Any help thanks Si

 

Long time since I did 68000, but off the top of my head...

to declare a string..

mystring dc.b "abcdef",0

to retrieve the ascii value just read the value out.. its stored as ascii anyway..

ie. to get the ascii value for the third char do this..

lea mystring,a0
moveq #2,d0 ;index
moveq #0,d1
move.b (a0,d0),d1 ;ascii for "c" is not stored in d1

Hope that helps...

 

your a life saver mate! ive got till 2morrow to figure it! any more would be marvellous!

cheers

Si

 

Define a string of your choice, no longer than twenty characters.
Write a FOR loop to add the ASCII codes of all characters in the string together,
and put the final result in register D5. The loop must also echo the characters
to the screen

 

mystring dc.b "mystring",0

lea mystring,a0 ;ptr to our string
moveq #0,d5 ;initialize result
.loop
moveq #0,d1 ;do this so our ascii code is a word
move.b (a0)+,d1 ;get next character
tst.b d1 ;zero?
beq .exit ;yes.. exit

add.w d1,d5 ;add current ascii value to total

bsr echo ;add your own echo function here, ascii in d1

bra .loop ;loop always
.exit
rts ;result is in d5



there you are... hope I'm on commision.. i'm unemployed you know!!

warning.. this may not work.. its a long time since i've done 68k...

 

I got back to uni monday to find it was in for friday! 4days to learn! which is solid because it doesnt make any sence! cheers anyway!

Si

 

doesnt work! doh doh

 

swap the bra for knickers.. might help?

Ill get my coat...

David

 

arghhhhh fooooooooooooool nar that works! it the declaring of the string it done like!
org $400
move.l #$FFF0,sp set the stack pointer
mystring DC.B '0123456789abcdef
LEA mystring,A0 A0->"0123456789abcdef"
moveq #0,d5
loop
moveq #0,d1
move.b (a0)+,d1
tst.b d1

add.w d1,d5
move.b #6,d0
trap #15
end $400

couple hours to go DOH DOH

 

You can't declare your string in the middle of the code.. it'll **** it up.. you have to move it outside of the code...

 

i know ! now ive changed to
ORG $400
MOVE.L #$FFF0,SP
LEA mystring,A0
LOOP: MOVE.B (A0)+,D1
BEQ NEXT
MOVE.B #6,D0
TRAP #15
BRA LOOP
NEXT: MOVE.B #9,d0
TRAP #15
mystring: DC.B 13,10,'Hello World!',0
END $400

printing to screen now need to count the characters!

 

I thought string declaration depended on the compiler that you were using?

*sigh* happy days of amiga demo coding... $dff180 and all that jazz...

What compiler are you using?

 

To count characters, subtract the original address of your string from the pointer that's in A0...

 

ITS THE motorola compiler @http://www-scm.tees.ac.uk/users/a.clements/welcome.htm

 

Wasn't the Amiga a great machine to code on.. brought back happy memories doing that little bit of code...

 

certainly was. You knew exactly what hw was in there, and exactly what you could get away with

 

Anyone used to use the K SEKA DEVPAC assembler ?

Ah, the Copper list! I had a major sprite multiplexor running on that machine!

Still got my Hardware Reference Manual somewhere! What a classic!

 

K Seka... ahhhh.. memories!!! bug ridden piece of crap that it was! graduated onto Devpac from there.. then onto the ultimate.. Snasm.. with remote debugging.. nice!

When I was moving house recently I found the Hardware Reference manual (bible) and the rom kernal one which cost me about £50 when I was a poor teenager...plus all my backup disks and crap like that. I'll have to take a look at them one of these days...

 

heh, love it!