Tadas Sasnauskas Tech/Engineering Blog

RC2014 retro computer kit

I finally found a DIY retro computer kit that I always wanted: RC2014 (available as a kit on Tindie marketplace). According to the author himself:

RC2014 is a simple 8 bit Z80 based modular computer. It is inspired by the home built computers of the late 70s and computer revolution of the early 80s. It is not a clone of anything specific, but there are ideas of the ZX81, UK101, S100 and Apple I in here.

It’s pretty much everything I always wanted to build myself (but never had enough patience & smarts to design it):

  • Uses Z80 cpu
  • Uses simple a simple bus with pluggable modules
  • Serial I/O for terminal

The kit itself

RC2014 kit

Probably my favourite thing here - the backplane (big square PCB). Very simple, can be easily done from veroboard + uses 0.1″ header sockets.

Assembled modules

5-6 hours and 500 - 600 solder joints later:

RC2014 assembled modules

Aside the back plane this kit includes:

Fully assembled

RC2014 fully assembled

Operation

ROM chip in the kit comes pre-flashed with (drumroll) Microsoft Basic dating back to 1978! And that can be accessed via serial console. So this means you can connect RC2014 to a terminal. But since I’m not that crazy yet and I do not have enough space for that I opted in for simple FTDI USB to serial cable + minicom.

Eventually, after some debugging and circuit troubleshooting I got this:

RC2014 running Microsoft Basic

I think it’s actually running some code written by Bill Gates himself. Other than that I cannot do much else without some kind of permanent storage device or at least a ROM programmer. And it’s also somewhat unstable but I do not have the gear to diagnose it. Good excuse to finally get an oscilloscope I always wanted, eh?