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I have an info. file which doesn't, I'm afraid, give the detailed
information you require, but FWIW here is what little information
about the parallel Interface I have here:
'ST parallel interface supports Centronics STROBE from the YM-2149
PSG for data synchronization and Centronics BUSY to the MK68901 MFP
(ACKNLG is not supported) for handshaking. Eight bits of read/write
data are handled through I/O port B on the PSG at a typical transfer
rate of 4000 bytes/second'
Parallel Port Pin Assignments:
ST DB 25S
PSG I/O A 1 --- Centronics STROBE ------->
PSG I/O B 2 <--- Data 0------------------->
PSG I/O B 3 <--- Data 1------------------->
PSG I/O B 4 <--- Data 2------------------->
PSG I/O B 5 <--- Data 3------------------->
PSG I/O B 6 <--- Data 4------------------->
PSG I/O B 7 <--- Data 5------------------->
PSG I/O B 8 <--- Data 6------------------->
PSG I/O B 9 <--- Data 7------------------->
MFP 11 <--- Centronics BUSY----------
18-25 -----------Ground-------------
Signal characteristics:
pin 1 TTL levels, active low.
pins 2-9 TTL levels.
pin 11 TTL levels, active high, 1k pullup resistor to +5V dc.
The data is believed accurate, hope this helps,
Best Regards,
Brian
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