Re: [hatari-devel] Possible problem with Pexec emulation

["Roger Burrows" <anodyne@xxxxxxxxxxxx>]

On 19 Nov 2022 at 6:10, Thorsten Otto wrote:
> 
> From my listing, that seems to be in hb_rect (the blitter function for filled
> rectangles), and the code around that address is
> 
> [00e12920] 3a84                      move.w    d4,(a5)
> [00e12922] 4ad5                      tas.b     (a5)
> [00e12924] 4e71                      nop       
> [00e12926] 6bfa                      bmi.s     $00E12922
> [00e12928] 5489                      addq.l    #2,a1
> [00e1292a] 51ce ffe0                 dbf       d6,$00E1290C
> 
> Which looks even more strange, since the bus error seem to be from the tas 
> instruction, but the move immediately before that was executed successfully?
> And why should a5 suddenly point to $e00000 instead of the blitter address? Or
> is that address maybe because the blitter tries to write $e00000?

I would assume the bus error occurs due to the blitter hardware trying to write 
to $e00000, and the PC just happens to be at $e12924 in the standard "wait for 
blitter" loop.

Roger