Since I am currently waiting for new PCBs to arrive, I thought to post some pictures of what my first (made between late 1990 and early 2000) working Z80 computer looked like. I was so relieved when one of my friends found these pictures from their archives. I didn’t think anybody even had any pictures about this project since back then we didn’t really have cameras, at least not many digital ones.
The main CPU board was hand drawn, first into paper, then manually transferred to the PCB for etching. It took around 8 hours just to transfer to the PCB using those awfully messy and wide pencils that they used to sell back then for drawing PCBs by hand. I don’t think they are even sold anymore. Fortunately I had couple of them still left (they were called dalon-pencils or something like that…?). This pencil is more than 15 years old and to my surprise still seems to work:
The second board was made by printing the PCB layout image first to paper using an old laser printer which I had removed the heater element from. Because of that the ink was not burned to the paper and it was easier to transfer the ink to the PCB using clothing iron. Nowadays it is just called toner transfer and it is a quite common method among hobbyist for producing self-made PCBs. Also there is no need to remove the heater element. Dunno why I did that, it seemed to work better that way.
This board actually had a quite well working operating system. It had logs, hex editor, real time clock for keeping uptime and almost working TCP/IP stack. Well, it could transfer UDP-packets and respond to ICMP-requests. The TCP side itself was bit too much for me back then since all of the code was written by myself in Z80 assembly, starting from translating NE2000 ISA network card drivers from linux kernel sources to Z80 assembly and so on.
Now for the goodies:
Oh, interesting. I’ve been thinking about building a Z80 machine with an ISA bus, but hadn’t seen anybody who’d actually done it before. 🙂