Still hundreds of wires to go

Serious life has been keeping me busy recently, so wire wrapping progress is very slow. I only managed to lay out the control module and wrap few wires. At this speed looks like it will take me several months to complete so I need to find some time and progress more. Meanwhile, here are the latest photos of the CPU under construction (click on images to enlarge to full-size jpegs). On the component side is a complete clock generation circuit and the control module. On the pin side, the clock generator is fully wrapped, whereas the control module has only the ICs’ power and ground pins tied to corresponding G (ground) and V (power) posts.

component side pin side

As you can see I have repositioned the clock generation circuitry (it now occupies a vertical board row, the one with a crystal). There were two reasons why I decided to unwrap my previous work and start over. First, my technique has improved and I am now able to wrap wires with not so much slack as before (compare the photos with those from previous post). Second, positioning the clock near the edge was silly. The best way to locate clock generation and control module (generating other clocked signals) is in the middle of the board, so that the length of wires carrying these signals is as short as possible. Now, clock and reset is in row N and microcode field decoding logic occupies row P.

One thing that bothers me now is board space. Just the clock and control module occupy almost half of the board, and there is still the ALU and register set to cram in (memory was originally planned to be on a separate board anyways). I think I will lay out some more components before I continue with wrapping. If it turns out that the board is to small for my entire CPU, I will have to locate the registers on a separate board, which is something I wanted to avoid.

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