For the past couple of years I’ve been working on two shields for programming very old EPROMs where hardware to program them is not readily available.
I’ve separated these into two different pages:
More about that here.
More about this one here.
Both of these shields are mentioned in this YouTube video (focused on 1702A)
If you like me you find yourself wanting an AT2XT adapter, you may have also discovered that they are not too easy to buy pre-made.
Project information here
Here is one I built on prototype board, using an AT to PS/2 Keyboard cable:
Without the IC Socket on it, it looks like this:
Once the IC Socket is fitted, the tails from the AT to PS/2 Keyboard can be attached like so:
I forgot to preserve a trace to connect the shield on mine, so I’ve had to connect that through that black wire separately.
Here is the underside:
In my case I used a PIC12F675 (which needs different code)
The last thing to do is wrap it in heatshrink tube:
A modified and compiled version for PIC12F675 can be downloaded here. I just fired it in with my Universal programmer, plugged it in and it worked perfectly first go.
If yours is using a PIC12F629 like the original design, get the firmware from the original project information page.