INES Mapper 133: Difference between revisions
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(make demarcation between different hardware more obvious) |
(why did I ever say that /ROMSEL wasn't part of the decoding logic? that's not what Санчез said) |
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Санчез, however, allocated Jovial Race to [[iNES Mapper 150]]. Either way, its UNIF MAPR is '''UNL-SA-72008'''. | Санчез, however, allocated Jovial Race to [[iNES Mapper 150]]. Either way, its UNIF MAPR is '''UNL-SA-72008'''. | ||
Mask: $ | Mask: $E100 | ||
$4100: [.... .PCC] - Select 32 KiB PRG bank and 8 KiB CHR bank | $4100: [.... .PCC] - Select 32 KiB PRG bank and 8 KiB CHR bank | ||
<hr> | <hr> | ||
Revision as of 00:17, 21 December 2017
GoodNES allocated iNES Mapper 133 for the Sachen unlicensed game "Jovial Race". It's almost identical to NINA-06.
Санчез, however, allocated Jovial Race to iNES Mapper 150. Either way, its UNIF MAPR is UNL-SA-72008.
Mask: $E100 $4100: [.... .PCC] - Select 32 KiB PRG bank and 8 KiB CHR bank
Another physical release instead wired a Namco 108 clone in an inscrutably complex way:
Mask: $E001
$8000: [..B. .B.B] - Select register
$8001: [...X XPCC] - Write value to register
| ||||
| ||++--- select 8 KiB CHR bank
| |+----- select 32 KiB PRG bank
+-+------ analog feedback path
Four of the registers produce an analog feedback path through the 108's CHR bankswitching registers:
| XX bits | behavior |
|---|---|
| $00 | if this register was selected, switch to using contents of register $04 |
| $08 | if this register was selected, switch to using contents of register $24 |
| $10 | if this register was selected, switch to using contents of register $01 |
| $18 | if this register was selected, switch to using contents of register $21 |
If this feedback path doesn't settle on one specific register, then the selected banks will rapidly switch between all the registers specified by the feedback path, and the 108 clone will get hot.
See also:
