This board is 1st one for NEDONAND project that was done in pcb-application from gEDA, because of its size (all previous board met free Eagle size limitations). This is 16-byte ROM for NEDONAND:
In every intersection above a diode could be put and it will drive that bit of those line down if this line is active (grounded) - so board should have 16 16-pin SIP sockets in order to make this ROM "re-programmable" manually:
4-bit address is going in through 4 header on the left and output is 12-pin header up with common memory interface that I will use for all memory boards for NEDONAND:
1) GND - ground 2) D0 - output bit 0 3) D1 - output bit 1 4) D2 - output bit 2 5) D3 - output bit 3 6) D4 - output bit 4 7) D5 - output bit 5 8) D6 - output bit 6 9) D7 - output bit 7 10) /RD (connected to LED in case of NEDONAND-16) 11) /CS (not connected in case of NEDONAND-16) 12) VCC - power +5V
Board had received from OSHPark and successfully tested - now it's also shared there...