nesdev.org

Posted: **Sat May 03, 2008 8:08 am**

I try build BIOHAZARD game cartridge. Its works, but i dont know how to connect WRAM/SRAM to it. Any ideas??

Schematics:
http://www.slanina.pl/gfx/168in1/168in1.pdf (mapper 15 - Contra 100in1 / Contra 168in1). I think Biohazard dont use PAL/GAL chip (its used only to control VRAM on 100in1/168in1 only)

Posted: **Sun May 04, 2008 11:06 am**

The PAL doesn't determine the A13 and A14 outputs to ROM? Only if they are simply passed through does the PAL not matter, not to say the same logic could be implemented with another discrete chip.

Since you already have /RD and /WR for the SRAM, you just need to decode the enable with a 3 input NAND gate:

Posted: **Mon May 05, 2008 2:06 am**

connect to A13/A14 cart connector or to PAL/ROM A13/A14??

Posted: **Mon May 05, 2008 10:27 am**

Connect them to the cart connector, ROM A13/A14 change with bankswitching.

Posted: **Mon May 05, 2008 1:43 pm**

sorry, but..

Where /ROMSEL , PHI2 and RW?? Cart connector? Please give me best famicom cart pinout scheme (i have probably old and simply version).

Posted: **Mon May 05, 2008 2:29 pm**

See P1 here: http://nesdev.com/Ntd_8bit.jpg

nesdev.org

Making BIOHAZARD cartridge

Making BIOHAZARD cartridge