Well, once again the folks at AtariAge are smart.
The usual cause of this problem is accidentally reading from a write-only register. On many systems, this will return the address you are trying to read from, but some will give garbage. But it's an easy mistake to miss:
lda #13 ; loads the value 13 into the accumulator
lda 13 ; loads the value at memory location 13 into the accumulator
; (which actually is a write-only register, so on some systems will accidentally load 13 into the register, but others will load garbage)
There's actually a setting in Stella (the emulator) that lets you force it to return garbage when reading from these registers, so by setting that flag, I can reproduce the problem that happens on the sixers. And knowing what sort of typo to look for, I can probably sort this out relatively quickly.
I started by blogging the process of porting my homebrew game Anguna from the Gameboy Advance to the Nintendo DS. Now, my random thoughts on development and chronicling whatever hobby project catches my fancy.
Monday, May 1, 2017
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NES Anguna
Well, I had a little bit of time still, while Frankengraphics is finishing up her game Project Blue, to have a little downtime on Halcyon, s...
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So I've recently purchased DosBox Turbo , the best (as far as I can find) implementation of DosBox for Android, and have been playing th...
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Well, I had a little bit of time still, while Frankengraphics is finishing up her game Project Blue, to have a little downtime on Halcyon, s...
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