Retro Computing

The Mark 2 Z80 project featured a pair of memory slots each capable of taking up to 32K of RAM. This meant that a full 64K of RAM could be used because the ROM image is copied from the PIC's memory at boot time. However that didn't seem like much to me so a banking system and MMU were in order. (Also I found I couldn't get the 32K RAMTRON FM1808 chips in DIP any more!)

Last week I was at the UK's first Vintage Computing Festival and picked up a new keyboard membrane for my ZX Spectrum and a replacement metal cover as the one that was on the speccy when I got it was a bit corroded. I took the opportunity to do another couple of jobs on the old computer.

It's been a (very) long time since the last update to this project. I've been busy on loads of new stuff for the project. The system is now capable of booting a binary from SD card or USB memory stick formatted in either FAT16 or FAT32. There's also full PS/2 keyboard support, a much more sophisticated interrupt control mechanism and a VGA display now.

I've started a new album of pictures of the Z80 project so far. It's currently got pictures of the two boards, and labelled pictures with the chip models and functions. I'm going to add schematics soon.

Check it out here: albums/Z80ProjectMark2