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Comment by rebootthesystem | Hacker News Reader

One of the first computers I designed and built was based on the 6502. It was a variant made by Rockwell. It was called R65F11. It came pre-loaded with FORTH in internal ROM.

One of the most challenging projects was designing a floppy disk controller from scratch (complete with the analog circuitry) to read and write to 5-1/4 and 8 inch floppy drives. Of course, I also had to write the driver and every other driver for the thing. In fact, I also had to write my own code editor.

The "pinnacle" was using a dozen of these to run a robot. They talked to each other over a serial loop.

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That's sounds friggin awesome fun! FORTH on a '6502' may be nightmarish to some but not to me. So many new 'words' to make.

It wasn't bad at all. I don't remember all the details. I do remember it was a tremendous amount of fun. The part I forgot to add was that every single board was wire-wrapped.

I also had to design and make various peripheral boards, such as: LED numeric display, DC motor drivers, analog and digital I/O, etc.

The entire computer was based on a 44 pin interconnecting bus. The CPU board could then address and talk to up to 16 cards, all memory mapped. No FPGA's or PAL's, all LS-TTL logic.

Sometimes I think it would be neat do put together a Kickstarter project for a kit and lesson plan to that would teach people to build a similar computer from scratch. Start with logic design, on through hand-building boards, bootstrapping in assembly, bringing-up FORTH, bring-up mass storage, writing a text editor and then some applications. Not sure how much interest there might be on such a thing these days. I know I would have been all over something like that way back then.

I just bought an RC2014 kit ( http://rc2014.co.uk ), which bears some similarity to what you're talking about. A larger community making cards for that computer would be really cool.

That is almost exactly what my self-designed/built computers looked like. The baseboards were longer and used an edge connector and card format that was popular at the time in industrial applications:

https://en.wikipedia.org/wiki/Edge_connector

This would be a fun project to work on if I could set aside some time. FIRST robotics build season (http://www.firstinspires.org/) is starting this weekend. I mentor one of the local teams. This sucks-up most of my free time for a few months.

Adding to my to-do list.

Awesome, I hope you can find the time to do it. I don't suppose the popular industrial bus with edge connectors was STD Bus, was it?

Yes, STD, but I came up with my own pinout.

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