[PLUG-TALK] Retro computing

[Keith Lofstrom]

On Fri, Jan 29, 2016 at 03:05:28AM -0800, Russell Senior wrote:
> I mentioned at the Advanced Topics talk that I had an old computer, my
> first, actually, an AT&T PC6300 purchased in 1986, with a 20MB

My first computer was a PDP8, circa 1968, when I was 15 years old. 
Papertape and teletypes, which I shared with other teenagers every
Thursday night through the Tektronix Explorer Scouts.  My first
program designed "Schmidt Trigger" two transistor bistable amplifiers.

My first personal computer was homebrew TTL and solder circa 1970,
didn't do much, long since discarded. 

I attempted to build my own solid state memories for that, actual
photomasking and chemistry, using a bizarre state-change effect I
had read about, not microchips or transistors.  Didn't work, the
effect wasn't reproducable.  Valuable early life lesson - don't
believe everything you read in the physics journals.

The next was S100, also mostly hand-wired.   Real engineers
program in solder.

I still have my 1977 4kB Commodore PET serial number 8, the
first "prebuilt" computer I ever owned.  I designed and built
an 8 inch CPM compatible floppy drive (translating between CPM
Basic to PET Basic on the fly), a 28kB external memory, and an
external full size keyboard for that.  What's a hard disk?

I also reverse-engineered and fixed errors in the PET's 14kB
ROM set (which Commodore purchased from M$ as object code, no
source).  I gave suggested patches to Commodore, which they
loved and sent to Redmond.  Bill Gates ignored the patches,
and used the code space I freed up to add a copyright notice,
absent from the original ROMs.  Gates never learned who I was,
but I heard secondhand stories that he threw a carpet-chewing
tantrum and made threats to the thief who "stole his software". 
I'm glad his meds are working better now.

I decided early on that I was too fussy and error-adverse
to write software for a living.   Instead, I design chips,
which almost always work the first time. 

Keith

-- 
Keith Lofstrom          keithl at keithl.com