Does anyone have a schematic of an MSX-MUSIC chip, either the original
FM-PAC or one of the others? I am building a board to connect an FM-PAC to
a Sega Master System expansion port for the FM sounds in many Master
System games, and I need to know what is done with the WE# line on the
YM2413.
I include technical info I have gathered thus far for your interest:
Sega Mark III FM Sound Expander I/O locations
F0 addr write
F1 data write
F2 ???? read/write (possibly the status register, but it writes to it too)
Possible implementation
A7 A6 A5 A4 A3 A2 A1 A0
1 1 1 1 0 0 -- -- A1 -> YM2413 WE# (?)
A0 -> YM2413 A0
address decode F0 - F3
MSX MSX-MUSIC I/O locations
7C addr write
7D data write
A7 A6 A5 A4 A3 A2 A1 A0
0 1 1 1 1 1 0 -- A0 -> YM2413 A0
what happens to YM2413 WE# ?
address decode 7C - 7D
Richard
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For info, see http://www.stack.nl/~wynke/MSX/listinfo.html
