I’m happy to report that the first build of COLE-1+ is up and running! JLCPCB created some beautiful boards and delivered them almost exactly a week after I put in my order. Here’s a photo of the assembled board:
There were only two fixes I had to make to the board after delivery. One is to add the missing pullup resistor on the ACIA IRQ line that I mentioned in my previous post; the other was a bodge wire to bring the A11 address line to the GAL. With those two fixes the board works exactly as expected.
Not only does this board run its original firmware just fine, it also runs a slightly modified version of the COLE–2 firmware, and this is the firmware version I am going to use going forward. My plan is to make this a universal BIOS for all of my future 65816 builds. This will allow me to continue development on the firmware while I plan out and design JRC-1.
In the end I am very happy with this build. I may do a re-spin of it down the road to correct the two errors I had to correct, and possibly add a power switch, just so that I can turn the unit off to pull the EEPROM without having to disconnect the USB serial cable. But, for now I’m going to concentrate on the firmware and on the JRC-1 design.