Jeff Barr's Blog

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Great Moments in Microprocessor History

IBM just published an informative article titled Great moments in microprocessor history. It was interesting to read through this and to see if I could come up with a personal link to each of the processors listed in the article. Here’s what I have so far:

  • Intel 4004 – In 1972 or 1973 my father was in the electronics distribution business. One day he gave me some Intel manuals and he started to tell me about this thing called a microprocessor. I remember reading those manuals on the deck of our house, and that the entire processing model made intuitive sense to me pretty much right away.
  • Intel 8080 – In 1975 I was working at the Retail Computer Store in Seattle. I saved my summer earnings and bought an Altair 8800 for myself.
  • Motorola 6800 – I never wrote any code for this machine, but I certainly sold some Altair 680′s and some Southwest Technical Products (SWTPC) goodies at the store.
  • MOS 6502 – My first real for-pay programming job was to write a macro assembler for the 6502, so I know this instruction set really well. Clean, elegant, and to the point. Even better, we were able to write macros (using my assembler) to fill in a few gaps in the instruction set, making it almost totally orthogonal.
  • LSI-11 – When we moved from Bellevue, Washington to Rockville, Maryland, I started working at the Computer Workshop in Rockville. I quickly latched on to the 16-bit Alpha Micro, and did a lot of cool stuff with that machine, none of which I can remember at any level of detail.
  • Motorola 68000 – While working for Intellimac in Rockville Maryland, I wrote a multi-user hypervisor which ran OS instances as tasks. This allowed us to run 4 copies of the Telesoft ROS operating system. The only redeeming feature of this OS was the fact that it ran the Telesoft Ada compiler. I wrote the boot ROM, the hypervisor, and all of the I/O drivers myself.
  • Zilog Z-80 – I wrote a bunch of Z-80 assembler code when I worked at Contel Information Systems. I wrote the code which ran some “toilet paper” printers on the floor of the American Stock Exchange, and I also re-implemented an X.25 protocol handler.
  • Intel 8086 – I didn’t do a whole lot of Intel coding. In fact, all I can remember writing is a very simple dynamic loader which used the dl() function to fault-in some pieces of code, resolve references to newly loaded functions, and then patch up the stack as if nothing had happened.

I think that’s about it! Ireally need to write up more of my career history at some point, before my brain turns to mush!

I did the first little bits here, and here as posts to the FoRK list