NES 2.0 Mapper 265: Difference between revisions

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(Created page with "Category:Multicart mappersNES 2.0 Mapper 265 is used for T-262 multicarts, all of which use 8 KiB of CHR-RAM. It latches both address and data bits. Its UNIF board name is...")
 
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             |      +--------- PRG-ROM banking mode
             |      +--------- PRG-ROM banking mode
             |                  0: Fixed Inner PRG-ROM bank 7 at $C000-$FFFF (UNROM)
             |                  0: Fixed Inner PRG-ROM bank 7 at $C000-$FFFF (UNROM)
             |                  1: Mirrored Inner PRG-ROM bank, selected by bits 0-2 (NROM-128)
             |                  1: Mirrored Inner PRG-ROM bank, selected by data latch(NROM-128)
             +----------------- Locking bit. 1=Prevent further writes from changing the latched
             +----------------- Locking bit. 1=Prevent further writes from changing the latched
                                 address bits. The data bits, which select the inner PRG bank,
                                 address bits. The data bits, which select the inner PRG bank,

Revision as of 21:14, 13 January 2018

NES 2.0 Mapper 265 is used for T-262 multicarts, all of which use 8 KiB of CHR-RAM. It latches both address and data bits. Its UNIF board name is BMC-T-262.

Address latch

Mask: $8000

$8000: A~[1.L. ..OO POO. ..M.]
            |    || |||    +-- Select nametable mirroring. 0=Vertical, 1=Horizontal
            |    ++-|++------- 128 KiB Outer PRG-ROM bank at $8000-$FFFF
            |       +--------- PRG-ROM banking mode
            |                   0: Fixed Inner PRG-ROM bank 7 at $C000-$FFFF (UNROM)
            |                   1: Mirrored Inner PRG-ROM bank, selected by data latch(NROM-128)
            +----------------- Locking bit. 1=Prevent further writes from changing the latched
                               address bits. The data bits, which select the inner PRG bank,
                               are still changeable.
                               

Data latch

Mask: $8000

$8000: 7654 3210
       ---------
       .... .PPP
             +++- Select 16 KiB Inner PRG-ROM bank at $8000-$BFFF,
                  also at $C000-$FFFF if address bit 7==1