HP 12C (1981 version) PCB photo wanted

[GreyUser]

Below is the original black diaper version of a 15C so it has the third chip, 12C is identical with the exception of that middle rom chip.

So in original 12C versions you have three:

Original flex version with separate keyboard (black diaper version)
2 chip single board version (as per your photo)
1 chip single board version (uses different LCD with 4:1 multiplex

The units I have are typically just bare pc boards as the units were cannibalized for their LCD’s to repair 11/15C’s. I could probably find complete units if it matters but boards I know I have.

If all you’re looking for are chip part numbers, those are all documented on Eric Smith’s Brouhaha site. http://www.brouhaha.com/~eric/hpcalc/chips/