NINA-003-006

NINA-003 and NINA-006 (author is embarrassed not to know which is which) are unlicensed boards produced by American Video Entertainment.

Overview

• PRG ROM size: up to 256 KB
• PRG ROM bank size: 32 KB
• PRG RAM: None
• CHR ROM capacity: up to 128 KB
• CHR bank size: 8 KB
• Nametable mirroring: hardwired to vertical or horizontal mirroring, or controlled by mapper (depending on type)
• Subject to bus conflicts: No

Banks

• CPU $8000-$FFFF: 32 KB switchable PRG ROM bank
• PPU $0000-$1FFF: 8 KB switchable CHR ROM bank

Registers

Control Register

This register is located at addresses:

F        bit      0
---- ---- ---- ----
010x xxx1 xxxx xxxx

That is, $4100-$41FF, $4300-$43FF, $45xx, $47xx, ..., $5Dxx, and $5Fxx.

7  bit  0
---- ----
MCPP PCCC
|||| ||||
|+||-|+++-- Select 8 KB CHR ROM bank for PPU $0000-$1FFF
| ++-+----- Select 32 KB PRG ROM bank for CPU $8000-$FFFF
+---------- Select mirroring (clear: horizontal, set: verical)

The mirroring bit should only be honored on the board type used by HES 6-in-1, Mind Blower Pak, and Total Funpak (HES), which is iNES mapper 113. On iNES mapper 79, this bit is ignored.