Haven't been here in a while, glad this resource is still alive. I've been wondering about how memory mappers get their signal to swap from one bank to another? Does the cpu code actually address ranges in the rom higher than the normal range without a mapper?
Recently 161 in 1 neo geo multi carts were reverse engineered enabling us to flash different games to it. The only down side is there is no NEO-SMA chip support. This chip handled encryption and bank switching. It's not a big deal because most games were bootleged to carts without encryption and the custom mapping. Except for Garou Mark of the Wolves. There is a neoragex rom set that is the final version, but the s rom is 512kb and thes 161 in 1 carts can only address 128kb for the s rom.
Was thinking about the possibility of piggy backing another flash chip onto the existing one, with some address pins lifted and /oe, then add a memory mapper circuit to get it up to 512kb. I'm not skilled enough to draw a working circuit for this from scratch, but if someone could point me in the right direction. Would making something like this work even be possible? Thank you.
https://github.com/xvortex/VTXCart/blob ... 61_cha.pdf
https://wiki.neogeodev.org/index.php?ti ... kswitching
The $7500~$753F area even words (32 total) contain a flag to indicate if the bank has to be changed for the corresponding tile line.
Recently 161 in 1 neo geo multi carts were reverse engineered enabling us to flash different games to it. The only down side is there is no NEO-SMA chip support. This chip handled encryption and bank switching. It's not a big deal because most games were bootleged to carts without encryption and the custom mapping. Except for Garou Mark of the Wolves. There is a neoragex rom set that is the final version, but the s rom is 512kb and thes 161 in 1 carts can only address 128kb for the s rom.
Was thinking about the possibility of piggy backing another flash chip onto the existing one, with some address pins lifted and /oe, then add a memory mapper circuit to get it up to 512kb. I'm not skilled enough to draw a working circuit for this from scratch, but if someone could point me in the right direction. Would making something like this work even be possible? Thank you.
https://github.com/xvortex/VTXCart/blob ... 61_cha.pdf
https://wiki.neogeodev.org/index.php?ti ... kswitching
The $7500~$753F area even words (32 total) contain a flag to indicate if the bank has to be changed for the corresponding tile line.
Statistics: Posted by darknezz19 — Sun Dec 24, 2023 10:18 pm — Replies 1 — Views 85