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H-blank Bit

Open Clownacy opened this issue 7 months ago • 0 comments

To quote Malachi...

I found the problem code. Basically at the end of my H_Int routine I had this
; a5 = vdp control reg
-    move.w    (a5),d0    ; wait until it's out of Hblank
    andi.w    #1<<2,d0
    bne.s    -
-    move.w    (a5),d0    ; now wait until it's in
    andi.w    #1<<2,d0
    beq.s    -

The first one was the problem, my assumption is that the register is always set to be in Hblank. Thankfully, that check was actually useless for this routine, so now you can play Sonic 2 as god inten-

Clownacy avatar Nov 27 '23 19:11 Clownacy