ET-3400 ROM - Almost there

Didn't get a lot done today. I did manage to finish off adding R10, R11 and R12 and have added the jumper pads for J10, J11 and J12 as well as the PRI/ALT pads completed. So that extra feature is completed. They are all accessible on the top of the PCB.

But, I should also add pads for the /CE pin too just in case I find that I need to isolate it later. There's not much room left on the top so that may be on the underside.

Also I am going to try and route those extra programming pins (RDY/BUSY, /WE and /CE) out somewhere accessible so a wire can be soldered onto them, or some similar trick for programming. These may also have to be routed on the underside to one edge.

Whatever I do, I won't be adding more layers, two layers and vias will have to do it or bust.

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