
Recently the MEGA65 project began selling their first batch of official development kits. Naturally, they sold out before I could get my hands on one; luckily for me (and many others), the latest bitstreams are still being built for the off-the-shelf Nexys A7–100T/Nexys 4-DDR FPGA development boards!
Now, by using an off-the-shelf FPGA development board in place of one of the custom designed MEGA65 r3 devkits, you’re obviously going to be missing a lot of the peripheral features right out of the gate (such as the injection molded keyboard + housing, expansion port, joyports, IEC, second SDcard, etc). However, with a little bit of luck and a lot of fudging, you can find substitute parts for all of these to wire into the IO expansion headers on the Nexys A7:
I’ve already decided on parts for the chassis and keyboard (pictured in the gallery above). I knew I was going to end up using one of my spare Commodore 64C shells for this, and since the MEGA65/C65 uses an extended keyboard layout similar to the PC/AT, i couldn’t just use a standard C64 keyboard assembly. I thought finding a fitting keyboard was going to be tough, but pretty quickly i managed to find a donor Thinkpad matrix that covers the c64c faceplate perfectly!
There’s still a lot that seperates this from a ‘complete’ devkit, but what I have working now is all I really need for a bare-minimum development platform!