chr bankswitching with 8k chr ram?

Discuss emulation of the Nintendo Entertainment System and Famicom.

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Dwedit
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chr bankswitching with 8k chr ram?

Post by Dwedit » Fri Sep 22, 2006 9:58 pm

(rewriting question...)
Does any game which uses 8k of CHR RAM (and no other chr ram/rom) do CHR bankswitching within the 8k? It would be quite silly to do so, since it's just rearranging the same memory into a different configuration, but do any games do it? The Waixing DQ4 pirate breaks if you emulate the MMC3 CHR bankswitching to change the mapping of CHR ram.
Last edited by Dwedit on Sat Sep 23, 2006 12:37 am, edited 1 time in total.
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Quietust
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Post by Quietust » Fri Sep 22, 2006 11:21 pm

Lagrange Point is the first game that comes to mind.
Pin-Bot/High Speed also switch their CHR RAM, but they have 64KB of CHR ROM in addition.
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Bregalad
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Post by Bregalad » Sat Sep 23, 2006 12:11 am

Romancia also does this, and the Title Screen screw up in some emulators that doesn't support this.
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Dwedit
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Post by Dwedit » Sat Sep 23, 2006 12:37 am

Quietust wrote:Lagrange Point is the first game that comes to mind.
Pin-Bot/High Speed also switch their CHR RAM, but they have 64KB of CHR ROM in addition.
edit:
TQROM games have more than 8k of total chr memory. I re-edited my post to bolden that restriction. Does lagrange point only have 8k of chr ram? Wow. It sure fooled me, looked like it had at least 16k, until I carefully examined it under fceuxd, indeed it has 8k.
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blargg
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Post by blargg » Sat Sep 23, 2006 3:37 am

The problem I encountered is that some games seem to switch CHR banks when using CHR RAM but expect that no switching occurs. Different board wiring would explain this, or just a problem in my emulator.

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