TR1ROM

TR1ROM (NES-TR1ROM) is one of the less common boards within the TxROM set. Like other TxROM boards, TR1ROM uses the Nintendo MMC3 ASIC. It should be noted that most probably, only american NES-TR1ROM boards have ever been produced, so this board has likely no 60-pin "HVC-TR1ROM" counterpart.

Overview

• PRG ROM size: 128, 256 or 512 KB (DIP-28/32 Nintendo pinout)
• PRG ROM bank size: 8 KB
• PRG RAM: None
• CHR capacity: 32 or 64 KB ROM (DIP-28 standard pinout)
• CHR bank size: 1 KB and 2 KB
• Nametable mirroring: Hardwired 4 screen mirroring
• Subject to bus conflicts: No

Hardware

For it's 4-screen mirroring, TR1ROM uses a 8 KB SRAM chip, but only 4 KB is actually used, and the 2 KB VRAM inside the console is always disabled.

See also

• Nintendo MMC3