Template:Octal D: Difference between revisions
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(We now have an article about mask ROM) |
(Per Bregalad: The other octal D latches don't have enough enable signals) |
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In theory, it would be possible to implement the bank select register with a | In theory, it would be possible to implement the bank select register with a [[74377|74HC377]] 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}}}. | ||
<noinclude> | <noinclude> | ||
{{Template:Octal D/doc}} | {{Template:Octal D/doc}} | ||
</noinclude> | </noinclude> | ||
Revision as of 15:59, 27 November 2010
In theory, it would be possible to implement the bank select register with a 74HC377 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}}
