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Graphics Interchange Format  |  2008-03-11  |  128.5 KB  |  2544x3296
   ocr: U1,U2 - - 906108-01 6526 COMPLEX INTERFACE ADAPTER (CIA) 1 VSS Ground Connection. 2-9 PAO-PA7 Parallel port a signals. Bidirectional parallel port. PIN 10-17 PBO-PB7 Parailel port b signals. Bidirectional parallel ASSIGNMENT port. 18 PC Handshake output. A low pulse is 40 ECNT 19 TOD Time generated of day after clock a read input. or write Programmable on port b. GND 1 PAO 2 39 ESP 50hz or 60hz input. PA1 3 38 ERSO 20 VCC 5VDC input. PA2 4 37 ERS1 21 IRQ Interrupt output to microprocessor input PA3 5 36 ERS2 IRO. PA4 6 35 ERS3 22 R/W READ/WRITE input from microprocessor's PA5- 7 34 FRES R/W ou ...