I mentioned in my old blog how taken I was by a very simple microprocessor-based microcomputer called the Cosmac ELF, dating back to 1976.

The microprocessor in question was the RCA 1802.

The microcomputer was really just for learning about computers. You could enter short programs via switches and then run them. To blink LEDs or whatever.

I have been thinking about this again recently and I have been amazed how much interesting stuff there is about this device on YouTube.

Here are some short videos showing people using their ELFs:

Entering a short program with commentary by DevilishDesign

Entering a short program by hvman

The ELF in this short video has some enhancements including the video interface from a subsequent “Popular Electronics” magazine:

With a display by Les Wright

There are other videos on the “Cosmac ELF 2000” and the “Cosmac ELF Membership Card”.

Then this is this long (46 mins!) video by youtuuba where he discusses exactly how he built his ELF: