I just finished wiring up the NVRAM chips to the computer. They are being addressed by a 8-bit program counter separate from the computer’s control counter. The control matrix changes its control word on the falling edge of the clock pulse. This allows the control to set up the 16-bit word, needed to tell which registers or operations are to be active, for the rising clock pulse.

There are a few problems, however, that have made this a bit more difficult than it should be. Since the NVRAM chips I am using are CMOS driven, the TTL chips do not always provide the correct voltage to address the NVRAM chips correctly. Inversely, the NVRAM chips also have the tenancy to output incompatible voltages in regards to TTL. To remedy this I am using the last of my 8-bit three state buffers to convert the input and output of the chips to higher voltages. After I get the NVRAM chips functioning correctly, I only have to add the input and write/run logic as well as the output and the computer is finished (circuit-wise). I will be designing a steampunk-themed case for the enclosure. The case will be the final step before this project is complete.

And Let the Testing Begin.


13 Responses to Test Time

  1. Bill Buzbee says:

    Congrats! Nicely done.

  2. John Gotts says:

    Impressive work, but trim those wires. As part of my time at U of M my partner and I wired up effectively an 80186 motherboard. It’s much nicer to be able to look at your work and be able see what’s going on, not to mention the ability to debug wiring mistakes.

    • Kyle says:

      Thank you. I might try wire wrapping if I choose to build a second computer (I still have my senior year to go, it would make a good project).

  3. Erfan says:

    Nicely done, I am impressed… so many wires… +50 geek credits for you 🙂

  4. thelma says:

    hiciste una computadora?

  5. I have no idea what you did but I think its awesome

  6. Marcelo says:

    wow, very impressive work, congrats! one day also I will try this!

  7. BlazeEagle says:

    A kind hello,

    I’m intrigued by your project & thought I’d share this site with you –

    They sell a variety of inexpensive circuit boards & they might have something beneficial to your project.

    I discovered them while researching a potential personal project.

    Kind regards

  8. Mario Gomez says:

    Hello, wow, very impressive work, congrats! one day also I will try this

  9. Agneepath says:

    This is very good amazing job guys!

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