the CE guy's ASM questions
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This code works for a very small amount of time after a keypress then spits what i assume is memory, why?

Code:

main:
 wait:
  call GetCSC
  or a, a
  jr z, wait
 cp a, 4
 jr z, up
 cp a, 3
 jr z, right
 cp a, 2
 jr z, left
 cp a, 1
 jr z, down
 cp a, 15
 jp nz, main
 ret
up:
 call ClrLCDFull
 call HomeUp
 ld hl, DispUp
 call PutS
right:
 call ClrLCDFull
 call HomeUp
 ld hl, DispRight
 call PutS
left:
 call ClrLCDFull
 call HomeUp
 ld hl, DispLeft
 call PutS
down:
 call ClrLCDFull
 call HomeUp
 ld hl, DispDown
 call PutS
DispUp:
 db "A" ,0
DispRight:
 db ">" ,0
DispLeft:
 db "<" ,0
DispDown:
 db "V" ,0

assembled with ez80 studio

Code:
ef7b211808f87436ff36216c3601c9

hamburger
the CE guy wrote:

Code:
up:
 call ClrLCDFull
 call HomeUp
 ld hl, DispUp
 call PutS
right:
 call ClrLCDFull
 call HomeUp
 ld hl, DispRight
 call PutS
left:
 call ClrLCDFull
 call HomeUp
 ld hl, DispLeft
 call PutS
down:
 call ClrLCDFull
 call HomeUp
 ld hl, DispDown
 call PutS
DispUp:
 db "A" ,0
DispRight:
 db ">" ,0
DispLeft:
 db "<" ,0
DispDown:
 db "V" ,0


Here is where I think the problem is. In each of the four branches, the OS returns from the call to PutS and executes the next branch. Then, the down branch starts executing data as code. I would put a ret block if you want to exit after that, or jr main if you want to continue the loop.
thx ill try that
Edit: it works perfectly

Code:
ef7b211808f87436ff36216c3601c9

hamburger
  
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