Template:Octal D: Difference between revisions
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(it's the same for a lot of discrete mappers) |
(We now have an article about mask ROM) |
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In theory, it would be possible to implement the bank select register with a 74373/74374/74377/74573 octal D latch, allowing up to {{{1}}}, {{{whynot|but due to mask ROM cost in the NES era, no non-pirate NES cart used this much memory}}}. | In theory, it would be possible to implement the bank select register with a 74373/74374/74377/74573 octal D latch, allowing up to {{{1}}}, {{{whynot|but due to mask [[ROM]] cost in the NES era, no non-pirate NES cart used this much memory}}}. | ||
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{{Template:Octal D/doc}} | {{Template:Octal D/doc}} | ||
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Revision as of 18:29, 6 February 2010
In theory, it would be possible to implement the bank select register with a 74373/74374/74377/74573 octal D latch, allowing up to {{{1}}}, but due to mask ROM cost in the NES era, no non-pirate NES cart used this much memory.
A lot of pages about 74HC161-based discrete logic mappers have similar wording.
Examples:
{{octal D|2 megabytes of PRG ROM}} {{octal D| 512 KB of PRG ROM and 128 KB of PRG ROM| whynot=but licensed games used an ASIC mapper instead for smaller banks}}