User:Lidnariq/Discrete Logic Table: Difference between revisions

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m (m180 only has 3 bits, but does have well-defined oversize)
m (mention cprom and m96 here)
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|-
|-
! colspan="1" rowspan="9"|32kB PRG bank bits !! 0  
! colspan="1" rowspan="9"|32kB PRG bank bits !! 0  
| [[NROM]] || [[Vs. System]] || [[CNROM]], [[iNES Mapper 087|87]], [[iNES Mapper 101|101]] ||  ||  ||  ||  ||  || oversize [[CNROM]]
| [[NROM]] || [[Vs. System]] || [[CNROM]], [[iNES Mapper 087|87]], [[iNES Mapper 101|101]], [[CPROM]]† ||  ||  ||  ||  ||  || oversize [[CNROM]]
|-
|-
!1  
!1  
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|-
|-
!2  
!2  
| [[AxROM|ANROM]]¹, [[BNROM]] ||  || [[GxROM|GNROM]], [[iNES Mapper 038|38]] || [[iNES Mapper 086|86]] || [[iNES Mapper 011|11]], [[iNES Mapper 036|36]], [[iNES Mapper 140|140]] ||  || oversize [[iNES Mapper 038|38]]
| [[AxROM|ANROM]]¹, [[BNROM]] ||  || [[GxROM|GNROM]], [[iNES Mapper 038|38]] || [[iNES Mapper 086|86]], [[iNES Mapper 096|96]]† || [[iNES Mapper 011|11]], [[iNES Mapper 036|36]], [[iNES Mapper 140|140]] ||  || oversize [[iNES Mapper 038|38]]
|-
|-
!3  
!3  
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† 4F+4 CHR-RAM banking, not 8 CHR-ROM banking
† 4F+4 or 4+4F CHR-RAM banking, not 8 CHR-ROM banking


¹ has mapper-controlled single-screen mirroring.
¹ has mapper-controlled single-screen mirroring.

Revision as of 04:01, 3 May 2013

It appears that all discrete logic mappers either switch 32kB at a time with no fixed bank ("GxROM-like"), or have a 16kB fixed bank and can switch the other ("UxROM-like"). The tables below illustrate the tradeoffs between CHR, PRG, and banking style.

GxROM-like 8kB CHR bank bits
0 1 2 3 4 5 6 7 8
32kB PRG bank bits 0 NROM Vs. System CNROM, 87, 101, CPROM oversize CNROM
1 AN1ROM¹ MHROM NINA-03/06
2 ANROM¹, BNROM GNROM, 38 86, 96 11, 36, 140 oversize 38
3 AOROM¹ 113
4 oversize AxROM¹ oversize GNROM
5
6
7
8 oversize BNROM


UxROM-like 8kB CHR bank bits
0 1 2 3 4 5 6
16kB PRG bank bits 2 168
3 UNROM, 94, 180 72, 78¹, 89¹, 93, 152¹
4 UOROM 70, 92
5
6 oversize 94
7
8 oversize UxROM, oversize 180


† 4F+4 or 4+4F CHR-RAM banking, not 8 CHR-ROM banking

¹ has mapper-controlled single-screen mirroring.