Epson 4S - Manual (Page 8)

Connector Pin Assignments
Parallel port connector pin assignments (CN3)
*Active low logic
Serial port connector pin assignments (CN4 and CN5)
VGA port connector pin assignments (CN2)
Power supply connector pin assignments (CN8)
Diskette drive connector pin assignments (J42)*
Hard disk drive connector pin assignments (J38)
*Active low logic
Epson EL 4S/33+
Speaker connector pin assignments (J34)
Optional game port connector pin assignments
Optional game port interface pin assignments (J1)
Option card riser board connector pin assignments (S1)
*All odd=numbered pins are grounds
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