[stella] mobile 48 bit sprite kernel

Subject: [stella] mobile 48 bit sprite kernel
From: "Eric Ball" <ericball@xxxxxxxxxxxx>
Date: Sat, 4 Jan 2003 15:18:13 -0500
I may be re-inventing the wheel here, but ever since Manuel posted his easy
16 bit sprite positioning routine, I've been wanting to use it to manipulate
48 bit sprites.  So I went back through the archives/dig to find the basic
48 bit / 6 digit routine.  The trick then was to make it self-timing.  My
original idea was to only have one WSYNC and strobe the HMOVE 24 cycles
before the first digit.  Fortunately, I found the post showing that unless
the HMOVE takes place shortly after WSYNC it doesn't work properly.

My test kernel appears to be successful except for when the sprite (random
data, so I could see any problems easily) is close to the left edge of the
screen.  I thought it might just be Z26, but my SuperCharger does the same
thing.  Can anyone shed some light on what is going on?

Attachment: sprite48.bin
Description: Binary data

Attachment: sprite48.asm
Description: Binary data

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