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Clock generator

A project log for YGREC16 - YG's 16bits Relay Electric Computer

Fork of #AMBAP, here I discuss about the physical implementation of the bitslice architecture with russian РЭС15 (see what I did here?)

Yann Guidon / YGDESYann Guidon / YGDES 12/05/2016 at 01:212 Comments

I'm starting easily with this simple circuit that I should finalise ASAP.

It's just another ring oscillator, with another twist. It now uses a dual power supply, capacitor coupling, and the second relay drives external signals. It's a "full" CC-PBRL system where the output's load will not disturb the frequency. It also helps a lot with the fanout.

Then, the LFSR will be quite similar, but with an added charge pump.

Discussions

Ted Yapo wrote 12/05/2016 at 01:27 point

It doesn't matter for a computer, but can you estimate the accuracy/drift of this clock?

Do you think it could be made suitably accurate for timekeeping?  Maybe with film capacitors?

  Are you sure? yes | no

Yann Guidon / YGDES wrote 12/05/2016 at 01:33 point

For this, I should get another rubidium time base, but there is another issue : the relays have a lot of switching noise that makes it hard for standard electronics to determine if and when a transition has finally occured.

This time I try to target 25-30Hz. I hope the rest of the circuit will work at this rate, in particular the memory. I provide a lot of separate signals that will make it easy to "compose" a sequencer, maybe through a diode matrix if it ever gets complex.

  Are you sure? yes | no