RE: [stella] I need your help for Climber5

Subject: RE: [stella] I need your help for Climber5
From: "Dennis Debro" <ddebro@xxxxxxxxxxxxx>
Date: Wed, 16 Oct 2002 11:06:58 -0400
Hi, Manuel.

>Actually, VBLANK + VSYNC + OVerscan ~ 70 lines, so that 
>is fine. The weird formula on the bottom of your kernel 
>might be the problem:
>   ldx tvType
>   lda KernelScanlines,x
>   sec
>   sbc #[[4+GRPHEIGHT]*NUMGRP]+1
>   tax
>Whatever you think it does, maybe it does different... 
The idea is the number of kernel lines used should be the (GRPHEIGHT+4)
* NUMGRP) +1. This would be 4 scan lines for the walkway + the 20 scan
lines for the player height * the number of groups which is 7 plus the
one scan line at the beginning of the frame. This should give me 169
scan lines to produce the playfield.

>Maybe if you'd replace that with:
>   ldy tvType
>   ldx RestScanlines,y
>At least it saves 2 bytes :-)
I like you suggestion :-) It makes perfect sense.

>Hm... at one point you're doing
>   sta WSYNC                     ; end the current scan 
>   sta VBLANK                    ; end the VBLANK period
>   sta HMOVE
>Maybe swapping HMOVE & VBLANK will help?
Tried it and it has no affect. I'll keep looking but I don't see where
the code is wrong. 

Thanks again.

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