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Author Topic: Mapper 91 to MMC5 Question  (Read 448 times)

Dracula X

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Mapper 91 to MMC5 Question
« on: October 26, 2020, 05:35:48 pm »
I'm trying to see if I can convert this to MMC5 but it looks like Mode 3 to me a little

UxROM:
Code: [Select]
CPU $8000-$BFFF: 16 KB switchable PRG ROM bank
CPU $C000-$FFFF: 16 KB PRG ROM bank, fixed to the last bank

MMC1:
Code: [Select]
CPU $6000-$7FFF: 8 KB PRG RAM bank, (optional)
CPU $8000-$BFFF: 16 KB PRG ROM bank, either switchable or fixed to the first bank
CPU $C000-$FFFF: 16 KB PRG ROM bank, either fixed to the last bank or switchable

Mapper 091:
Code: [Select]
CPU $8000-$9FFF: 8 KiB switchable PRG-ROM bank
CPU $A000-$BFFF: 8 KiB switchable PRG-ROM bank
CPU $C000-$FFFF: 16 KiB PRG-ROM bank, hard-wired to last bank

MMC3:
Code: [Select]
CPU $6000-$7FFF: 8 KB PRG RAM bank (optional)
CPU $8000-$9FFF (or $C000-$DFFF): 8 KB switchable PRG ROM bank
CPU $A000-$BFFF: 8 KB switchable PRG ROM bank
CPU $C000-$DFFF (or $8000-$9FFF): 8 KB PRG ROM bank, fixed to the second-last bank
CPU $E000-$FFFF: 8 KB PRG ROM bank, fixed to the last bank

Should I change it to mode 1 to work around it or change it to mode 3?


« Last Edit: October 26, 2020, 05:42:11 pm by Dracula X »
I might go back to Thunder Force II hacking again.

Cyneprepou4uk

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Re: Mapper 91 to MMC5 Question
« Reply #1 on: October 26, 2020, 05:50:28 pm »
If your game always swaps both banks at the same time, then you can work with either 1 or 3 mode. Otherwise mode 3 only.

Why do you post info about other mappers besides 091 and MMC5? Never include irrelevant stuff in technical questions.
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Dracula X

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Re: Mapper 91 to MMC5 Question
« Reply #2 on: October 26, 2020, 05:52:50 pm »
1. I'll remember that next time!

2. So I won't make a mistake with the wrong choice.
I might go back to Thunder Force II hacking again.