Wednesday, 1 June 2011

Elliot 803

This is a video of an Elliott 803 computer. It's the first machine I ever wrote a programme for. The whole thing was the size of a room. The only input and output devices used five-column paper tape.

We prepared our programmes on teletype machines. Then we used little switches on the console to boot the machine with the Algol compiler, and read our programmes in. I remember them as toggle switches, but they seem to be buttons here, so I must have got that muddled.

After a while the machine punched out another reel of paper tape containing the executable programme that it had generated. We rebooted again with the little switches to load the executable, and waited for the results.

My most successful programme generated solution to "Seven Bridges of Königsberg" type of problems, which it output as yet another reel of paper tape. That went into a pen plotter for the final result. It's (more or less) a standard routing problem, and the algorithm I used was pretty crude, but I was very proud of it at the time. Somewhere I think I still have the listing and paper tape, but years ago when I took another look at it I realised that there was a bug that my test cases hadn't picked up. I was gutted.

This must have been in the late 60's. I was still at school, and immensely lucky in those days and at that age, to have access to this technology. Happy memories, but things have moved on a little since then. It's amazing how evocative the various sounds are.

I hadn't realised that they had one working at the National Museum of Computing in Bletchley Park. I must plan a visit.

1 comment:

Doug said...

I haven't been to Bletchley Park for a few years but I found it very interesting. I think it was in the news recently having acquired something important / significant.

All the best.