Talk:VRC6

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Revision as of 15:22, 23 October 2013 by Quietust (talk | contribs)
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The VRC6 documentation (currently linked from here) seems to indicate that register $B003 has quite a lot more bits than we currently know about:

  • D0/D1: CHR/NT Bank mode
    • mode 0 - normal
    • mode 1 - regs 0-3 select 2KB CHR banks, regs 4-7 select nametable banks
    • mode 2 - regs 0-3 select 1KB CHR banks at 0000-0FFF, regs 4-5 select 2KB CHR banks at 1000-1FFF, regs 6-7 select nametable banks (controlled by mirroring)
    • mode 3 - pattern tables seemingly also get mapped into the nametables?
  • D2/D3: mirroring control
  • D4: 0 = Use extra 8KB CHR RAM for nametables (in bank modes 1-3); 1 = Use CHR ROM for nametables
  • D5: something related to CHR ROM?
  • D7: SRAM enable (1 = enable)

--Quietust (talk) 09:07, 23 October 2013 (MDT)