Chris's Early Computers

My first computer was essentially hand-built using these:

solderless breadboard

(My gosh, Jameco is still in business! I used to order chips, etc. from them.)

I used the 3-chip Intel 8080 chipset that I ordered directly from Intel (yes, you could do that):

Intel 8080

along with some TTL logic chips and some UART chips:

General Instruments AY5-1013 UART

I used one UART set to 5-bit characters to talk to:

Baudot teletype

The teletype I had was the same colour as in the first picture there. It had the paper-tape reader and punch parts as well as the main teletype. It was huge and heavy.

I tried to use the other UART to talk to a cassette recorder to save/restore programs, but it never worked. I found out later that the Radio Shack computer cassette decks were special - mine was just a regular audio one.

I also build a wooden "console" with switches and LEDs by which I could write directly to the SRAM to enter code.

The 8080 chip had an output pin showing "interrupts enabled". One of my very earliest programs just did a counter to toggle that pin back and forth every second or so. With an analog multimeter connected to it, I could see the program run.

 

I think this was my first (commercial) computer:

Exidy Sorcerer

I had an S-100 expansion box and some kind of floppy. It was mostly in my office in the General Services Building on the University of Alberta campus. Work on my Draco compiler was done on it, and the compiler first ran natively on it. I eventually sold the system to a local fellow to use as a backup for his.

 

My second computer was one of these:

Radio Shack Color Computer

I recall Dan and I wrote some 6809 assembler for the:

"railroad algorithm"

in a very few bytes of code. I think I mostly used the machine for playing games, though.

 

My third system was my Godbout Compupro system. It was large and quite expensive (about $10,000 in the 1980's).

I had a huge S-100 chassis, with space for 20 S-100 boards. I had in it:

CPU8085-88

Disk 1

System Support 1

Spectrum

along with, I think:

RAM16

along with someone else's 256K DRAM board.

I also later got a different graphics board, that had a TI graphics chip that provided some hardware sprites.

I also had a huge separate box with a pair of 8-inch floppy drives in it, and an:

ADDS Viewpoint terminal

to talk to it all. On that system I wrote and ran my "Explore" game system (somewhat like the early Ultima games) (a couple of pictures from the Amiga version):

Amiga Explore

 

I eventually bought a Motorola MC68000-based Commodore Amiga computer:

Amiga 1000

I quite liked this computer - it had a nice keyboard and was very quiet. Danny and I sort-of tried to go commerical with work on this, and we bought him one through our becoming official Amiga developers. I had the 256K RAM expansion as well. Last time I tried it, this computer still worked, but the external floppy drive wouldn't read disks.

On the Compupro CP/M system I wrote a cross-compiler version of my Draco compiler, to produce 68000 object code. I had the two computers connected via parallel ports, and had some custom code on both to enable transfers. Eventually the Amiga version of Draco was self-supporting.

 

I tried to get a reliable hard drive for the A1000, but failed. So, instead, I bought an A2000:

Amiga 2000

which eventually became an A2500.

This got loaned to Stuart for a while, since I had moved on.

 

Next, I moved up to an A3000:

Amiga 3000

Nice machine. Eventually they became fairly cheap, and I bought a second one as a backup. I think that ended up with Craig.

 

My final step was an A4000T:

Amiga 4000T

I ordered it the day I heard that Amiga was going out of business. I was in the middle of doing lots of programming on Amiga's, and decided that for me, not having to choose a whole different architecture and OS was worth it. The A4000T turned out to be a nice, reliable machine.

 

After that was a series of Linux computers. The current "quiet" one is the 3rd in that line.


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