So, this summer, I made this adapter to use an ATF1508 CPLD as a replacement of the original Motorola Gate array at the heart of the Thomson MO5. I just did the hardware part, I got the VHDL from one of the guy who did the reverse engineering one or two decades ago.
This is my first time with soldering TQFP and 0603 packages, and it went well.
There are two projects :
- The adapter project : https://github.com/sporniket/thomson-mo ... w--atf1508 there is an SVF file in the fusemap folder, to program the CPLD.
- A custom development board to program and verify : https://github.com/sporniket/thomson-mo ... ment-board this is a convenient rig to hold the remake, the USB-dongle of a FT232H, and an optionnal DC-DC 5V->12V converter to optionnaly force JTAG functionnality by feeding Vpp on the dedicated pin of the CPLD (you may need this when you buy from alternative sources instead of mouser/lcsc/rs/etc...). The "verify" part is just a witness LED that will blink at 1Hz when the CPLD generates the 1MHz clock signal.
I did not shot the assembly -seeing the top of my head for an substancial time would not be that interesting imho-, but I did shot the final stage of programming, installing the remake and switching the computer on :
