Final Check

I checked as much as I could. Particularly the 82C52 as it is new. Changed IO_RD/IO_WR to MEM_RD/MEM_WR (that would make the board useless).

Updated the crystal frequency to 10MHz.

So now I just have to wait a week or so for the PCB to arrive.

Final Schematic:

As much as I try I still find errors after sending the PCB to be manufactured.

I updated the labels on UM61512 to make it clearer but I connected CE2 to CS_RAM rather than VCC. No matter, I can patch the board.

AlanX