This is great! You've earned a +1 respect!

I remember one time when I was working on Pyoro I had the weirdest bug that seemingly occurred at random and couldn't be traced back anywhere.  It took me a week to find but eventually, I found it and fixed it.  I had forgotten to back up the ix register during my interrupt routine.  If you're using custom interrupts, make sure the routine is working right.

Another thought, is your program nearing 8kb in size?  Any code larger than that will cause a crash due to execution protection on the last page.  Try replacing the commented out part in your example with nops instead of the loads, I bet it has something to do with program size rather than the particular instructions.

Also, where are screenx and screeny?  You're not writing over any OS variables right?

I don't use custom interrupts. I turn interupts off at the beginning of my program, and turn them back on at the end of my program. I never had problems with this, so I don't see why it would give problems now.

Further, my program is only 2kb in size(on the calc), including a large LUT and a list of variables. Also, replacing the instructions with nops (even with a lot of them) doesn't let my program crash

screenx and screeny are variables defined in the program itself, so i'm not overwriting any OS vars.

I also tried to push ix at the beginning of my program, and pop it afterward. This didn't help either

Thanks. It all works now

that one is corrupted too

Quote from: ben_g on June 05, 2011, 03:26:16 pm

Quote from: Keoni29 on June 05, 2011, 03:25:15 pm

Why do you use the old theme?

becouse i don't know how to set the theme

Personalization Settings, accessed through Panel Control.

I think i'm going to keep it like this anyway.

btw i can't even find the personalisation settings.

My desktop:

Yes, that routine has a ret behind it, i just forgot to copy it.

MulFP looks like this:MulFP:
  ;Multiplies 2 16bit fixed-point numbers
  ;IN: de, bc
  ;OUT: de * bc in hl
  ;DESTROYS: af, bc, de, hl
  bit 7, d
  jr nz, _MulFP_FirstNeg
  bit 7, b
  jr nz, _MulFP_AnsNeg
  jr z, _MulFP_AnsPos
_MulFP_FirstNeg:
  bit 7, b
  jr nz, _MulFP_AnsPos
_MulFP_AnsNeg:
  ld a, 1
  push af
  jr _MulFP_Cont
_MulFP_AnsPos:
  ld a, 0
  push af
_MulFP_Cont:
  bit 7, b
  jr z, _MulFP_BCPos
  call NegBC
_MulFP_BCPos:
  bit 7, d
  jr z, _MulFP_DEPos
  call NegDE
_MulFP_DEPos:
  call Mul16 
  ld l, h
  ld h, e
  pop af
  cp 1
  call z, NegHL
  ret
and it uses the Mul16 routine which looks like this:Mul16:                           ; This routine performs the operation DEHL=BC*DE
  ld hl,0
  ld a,16
Mul16Loop:
  add hl,hl
  rl e
  rl d
  jp nc,NoMul16
  add hl,bc
  jp nc,NoMul16
  inc de
NoMul16:
  dec a
  jp nz,Mul16Loop
  ret

The only thing that i was able to find out while debugging was that it repeated some code over and over again. That was by repeating step by step. as soon as i click 'run', the calc crashes.
Further, i found out that when i call the routine twice, it doesn't clear the ram but ends the program.

I don't really get this:

Clears ram	doesn't clear the ram
Code: [Select]   ld hl, (screenx)   ld d, 1   ld e, 0   call SubFP   ld b, h \ ld c, l   ld de, 94   call MulFP   ld (screenx), hl   ld hl, (screeny)   ld d, 1   ld e, 0   call SubFP   ld b, h \ ld c, l   ld de, 62   call MulFP   ld (screeny), hl   ret	Code: [Select]   ld hl, (screenx)   ;ld d, 1   ;ld e, 0   call SubFP   ld b, h \ ld c, l   ld de, 94   call MulFP   ld (screenx), hl   ld hl, (screeny)   ;ld d, 1   ;ld e, 0   call SubFP   ld b, h \ ld c, l   ld de, 62   call MulFP   ld (screeny), hl   ret

In the left part, it clears the ram, while in the right part, it doesn't clear the ram while i have only comented out a few ld commands.

coul someone help please?