Another of the simple boards, the 8K ROM board is little more than a breakout board for a 27C64 EPROM and little bit of decoding for the enable line


Data lines D0 – D7 and address lines A0 – A12 connect directly to the EPROM for 8K of addressable memory.  Address lines A13, A14 & A15 need to all be low for the Chip Enable to be triggered, which places it in the ox000 – 0x1FFF address space.  The RD and MREQ need to be low to trigger the Output Enable

Click the image below for schematics in PDF format


Bill of Materials

  • PCB
  • 34 pin R/A header
  • 28 pin wide DIL socket
  • 14 pin narrow DIL socket
  • 27C64 EPROM
  • 74ls32