I've finally built a second revision of the latest board, which fixes the issue with the CompactFlash card's DSACK generation. See here for more details. With the latest board, it can now load and boot the kernel from the CompactFlash card. I fixed the mistaken footprints for the 74HC253 chips as well, and spaced the logic chips out more, to make it easier to assemble and bodge. It was a dream to assembly, by comparison to the first revision. I think it took me 4 to 6 hours in total, where the previous revision took 4 days of 6 - 8h each.
I honestly haven't touched it much after getting it working. I've been distracted by another project. But eventually I'll get around to modifying the kernel to allow virtual memory and isolated address spaces for processes, as well as work on the eventual multi-card computer version.
The board will run the monitor software and boot the OS. I still have a problem with the CompactFlash card, but everything else seems to be working. I'm so happy, especially after making a mistake and using the wrong footprint for the two 16SSOP logic chips. I had to bend the pins under the package and try to solder them upside down, without hot air, just a fine tipped soldering iron.
The k30-SBC boards arrived yesterday and the most minimal build to get the 68030 free running is working!
The oscilloscope screenshot shows address line 4 switching. Phew! My eyes are sore from looking at those fine pitched pins to inspect them. I'll finish the rest of it tomorrow
I've been working on an emulator written in Rust called Moa which is capable of emulating Computie. It will open two pseudoterminals on the host linux computer for the TTY and SLIP connections that Computie OS uses, and launches a terminal emulator to connect to the TTY. Check it out on github for more info
transistor_fet
