MV1A PALs: Difference between revisions
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(Created page with "The {{PCB|MV1A}} MVS boards have two https://en.wikipedia.org/wiki/Programmable_Array_Logic PAL PAL20V8H-15 chips which are used to provide some of {{Chipname|NEO-C1}}'s f...") |
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Does address decoding. | Does some address decoding. Pin 1 might be AS instead of RW. | ||
[[File:SNK1A_pinout.png]] | [[File:SNK1A_pinout.png]] | ||
Revision as of 22:27, 5 October 2023
The MV1A MVS boards have two [PAL] PAL20V8H-15 chips which are used to provide some of NEO-C1's functions. If any of them fails, the board certainly won't start up.
They can be replaced with new or working chips programmed with the following JEDEC files:
SNK1A
Does some address decoding. Pin 1 might be AS instead of RW.
JEDEC file: File:SNK1A.zip
SNK1B
Generates the DTACK signal.
The CN2* inputs are probably connected to the cartridge ROM speed configuration pins (ROMWAIT, PWAIT...)
JEDEC file: File:SNK1B.zip