TIM 8 is all good, but writing programs takes ages as they have to be printed out in stages. Then if there's a mistake you have to print it all out again. Since I had started to write more and more complex programs (Euclid's algorithm, solving simultaneous equations, etc.) it was becoming almost impossible, and these programs have so far only have been successfully run on my simulator.

What I needed was a stored program computer, which was fast and had plenty of memory. I got fairly good at designing relay logic, but that is realistically not a very useful area to be an expert in. Besides the TIM project is all about learning new skills, and relay logic is no longer a new skill to me. So I've decided to come forward about 30 years in my computer design.

Obviously, building a computer out of IC's is too easy. There are several around, and it's a fairly well established science. However I noticed there was a distinct lack of Diode-Transistor Logic (or DTL) computers, historical or otherwise. There was probably a good reason for this, but I have decided to try and rectify the problem regardless.

Transistors and I have never really got on very well; any project I'd done using transistors had failed miserably unless I was following a circuit diagram. So this was a good opportunity to finally learn how to use them for something other than producing smoke.

As this is quite a large project, I've split it into sections:


Prototyping and Testing




For videos on the project, visit http://www.youtube.com/user/rapidrory

Both the project and this site are still a work in progress, so check back here for updates. Last update was on 12/03/13


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