There's no real heat from it so all is good - I'm just irritated with myself for forgetting to put the pad in. Good idea re the heatsink though.
Here's the board built up and complete apart from a zener diode which I need to find. Current draw is 80mA while running NOPs from the EEPROM. Most of that is probably going to the GAL.
Board stats (for those interested):
Name: 65C02 GPD (General Purpose Design)
CPU: WDC 65C02S
CLOCK: Internal or external source selectable using jumper
RAM: 32kB, 55ns ($0000-$7FFF)
EEPROM: 30kB, 45ns ($8400-$FFFF)
I/O: 1x 65C22S VIA ($8100-$810F)
I/O: 1x 65C51N ACIA (using MAX238) ($8200-$8203) - for RS232C
Power In: 7-20V DC regulated
Power Out: 3x 5V DC out, 1x 7-20V out
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Testing:
So far it runs at 1MHz fine (2MHz split down to 1MHz) with NOP instructions from EEPROM. Internal and external clock source selection works fine as does reading address and data bus from the bus connectors (the IDC style sockets on the board).
The 3.2mm holes are perfect for the motherboard standoffs found in PCs - thanks to all those who made suggestions in this area.
My only real issue is tryign to get the flippin' flux off of the PCB. Isoprop and a short bristle brush + lots of scrubbing. It's coming off slowly. Also tried using low fibre kitchen towels and scrubbing through that with Isoprop to try and lift the flux off.
Anyone got any tips?
Next steps: RAM tests, I/O tests (probably output to an LCD)