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I did a Buzz & Waldog hack to MMC3 and didn't realize, the game uses One-Screen Mirroring (like Battletoads). MMC3 only has horizontal and vertical settings. But, would it be possible to modify your pcb board/cartridge to make it One-Screen mirroring?

If it's possible how would you do it? I take it you have to steal CIRAM A10, but I'm unclear what you need to do with it after that.

One word: TLSROM. Or is the CHR too big?

Ok, but then how do I add WRAM? The game is 128k prg / 128kb chr, 8k wram/prgram ($6000), and 1 screen mirroring. Would TKSROM be the same thing with WRAM?

Edit: http://nesdevwiki.org/index.php/INES_Mapper_118 So couldn't I cut CIRAM A10 going to the MMC3, and wire it to CHR A16 to convert an MMC3 board to 1 screen mirroring?

Yes, I guess you could modify any TKROM and TSROM board easily to have TLSROM like mirroring. As you said, connect CIRAM A10 (on the cart edge) on CHR A16 (MMC3) instead of normal CIRAM A10 (MMC3) pin. Also make sure your hack work with mapper 118 before doing that.

The hack does work on 118. Tested on Nestopia, Nintendulator, and the PowerPAK.

Bregalad wrote:Yes, I guess you could modify any TKROM and TSROM board easily to have TLSROM like mirroring. As you said, connect CIRAM A10 (on the cart edge) on CHR A16 (MMC3) instead of normal CIRAM A10 (MMC3) pin. Also make sure your hack work with mapper 118 before doing that.

Just to be clear, do you mean MMC3 pin 44 to RAM pin 21?

*EDIT*,

Actually when I checked it again, do you mean the cart pin 22 to mmc3 pin 44?

Not only another bump, but in reading on the wiki it says CHR A17, instead of 16.
Im getting a little lost here.

I'm pretty sure it's CHR A17, the MMC3 output bit that corresponds to bit 7 of the CHR bank registers.

Ok thanks!

So wiring wise, you'd cut the trace for MMC3s CIRAM 10 (pin 10), and wire it directly to CHR ROM pin 1 bent up?

EDIT. I wasn't even thinking that Pin 1 is VPP. Hole 1 is CHR A17 and pin 30 on the EPROM is CHR A17 for 256k, but TLSROM has a CHR limit of 128k. Theres something simple im missing here.

guitarzombie wrote:Ok thanks!

So wiring wise, you'd cut the trace for MMC3s CIRAM 10 (pin 10), and wire it directly to CHR ROM pin 1 bent up?

EDIT. I wasn't even thinking that Pin 1 is VPP. Hole 1 is CHR A17 and pin 30 on the EPROM is CHR A17 for 256k, but TLSROM has a CHR limit of 128k. Theres something simple im missing here.

Sorry to resurrect an old thread, but everything I've read states that the TLSROM CHR size limit is 128KB, other than official specs, is there any way to go up to 256KB through some sort of PCB modification?

Thanks!

TLSROM uses the bit that would have let you have 256 KiB (instead of 128KiB) of CHR to instead control mirroring.

As tepples is fond of pointing out, a game could have suffered through having these bits control both the MSB of CHR bank as well as CIRAM A10. If you want to modify an existing board to do this, it's easy: what would be CHR A17 is currently CIRAM A10. Just connect it also.