Talk:INES Mapper 093: Difference between revisions
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No-one has ever done this.—[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 12:12, 12 May 2013 (MDT) | No-one has ever done this.—[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 12:12, 12 May 2013 (MDT) | ||
: Are you capable of running a test ROM for bankable CHR RAM? It could be used as part of the test suite for this mapper's NES 2.0 representation. --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 15:24, 12 May 2013 (MDT) | : Are you capable of running a test ROM for bankable CHR RAM? It could be used as part of the test suite for this mapper's NES 2.0 representation. --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 15:24, 12 May 2013 (MDT) | ||
:: No, I don't have the parts on hand. I think I'd rather define all discrete logic mappers as "can be used to bank CHR-RAM in place of CHR-ROM if the NES2.0 header specifies no CHR ROM and more than 8KiB CHR RAM" rather than formalizing the above idiosyncrasy of noncontiguous bits; e.g. m70 with CHR-RAM is strictly superior for homebrew because it supports 4 bits for each of CHR and PRG instead of 2 and 3, respectively. —[[User:Lidnariq|Lidnariq]] ([[User talk:Lidnariq|talk]]) 16:33, 12 May 2013 (MDT) | |||
Revision as of 22:33, 12 May 2013
Banking CHRRAM
If, for some reason, you were to remove the 8KiB CHR RAM IC on the Sunsoft-3R PCB and replace it specifically with a 62256 (the largest compatible 28-pin RAM), the functionality of that PCB would then become:
$8000-FFFF: [.PPP .C.C]
P = PRG Reg (16k @ $8000)
C = 8KiB CHR RAM bank
No-one has ever done this.—Lidnariq (talk) 12:12, 12 May 2013 (MDT)
- Are you capable of running a test ROM for bankable CHR RAM? It could be used as part of the test suite for this mapper's NES 2.0 representation. --Tepples (talk) 15:24, 12 May 2013 (MDT)
- No, I don't have the parts on hand. I think I'd rather define all discrete logic mappers as "can be used to bank CHR-RAM in place of CHR-ROM if the NES2.0 header specifies no CHR ROM and more than 8KiB CHR RAM" rather than formalizing the above idiosyncrasy of noncontiguous bits; e.g. m70 with CHR-RAM is strictly superior for homebrew because it supports 4 bits for each of CHR and PRG instead of 2 and 3, respectively. —Lidnariq (talk) 16:33, 12 May 2013 (MDT)
