TVROM

From NESdev Wiki
Revision as of 17:16, 26 January 2010 by Tepples (talk | contribs) (→‎Hardware: what we discovered for rad racer)
Jump to navigationJump to search

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

Overview

  • PRG ROM size: 64 KB (DIP-28 Nintendo pinout)
  • PRG ROM bank size: 8 KB
  • PRG RAM: None
  • CHR capacity: 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 its 4-screen mirroring, this boards uses a 8 KB SRAM chip, but only 4 KB is actually used. The 2 KB VRAM inside of the console is always disabled, and the CIRAM A10 pin of the MMC3 doesn't go to anything.

See also