On 3/5/26 14:28, MRAB wrote:
On 05/03/2026 17:42, Charlie Gibbs wrote:
On 2026-03-05, Peter Flass <[email protected]> wrote:
On 3/4/26 15:35, Lawrence D’Oliveiro wrote:
On Wed, 4 Mar 2026 14:09:58 -0700, Peter Flass wrote:
On 3/4/26 13:29, Carlos E.R. wrote:
On 2026-03-04 21:01, Ted Nolan <tednolan> wrote:
.
A man with one clock knows what time it is. A man with two is
never quite sure...
Experimental science would not agree.
You would need at least three.
Three would be better than two, but two is already enough to come up
with an error estimate on the measurement.
No, because if two don't agree, one could be just plain wrong. The
Space
Shuttle system had three processors run the same computation as a
check.
And, IIRC, the third one was built and programmed by a different outfit.
The shuttle actually had five computers.
At least one of which was based on the RCA 1802 micro which I used to make
a tape machine editor to add a new digital acadamy leader and the audio
tones
on channel 2 of the Sony 2800 series of 3/4" video tape recorders in
1978 using
a station break sequencer that was powered by a Fairchild F8, another quite
primitive micro. The 1802 had 16, 16 bit registers you had to load 8
bits at a
time, any one of which could be assigned as one of 3 functions, program
counter, stack pointer, or dma address register. No subroutine call and
return
until someone wrote them and published them in McGraw-Hills Electronics
magazine.
Memory back then was gawd awful expen$ive, I had to pay $400 for 4k of
static ram because the 1802 came out b4 dynamic ram & refresh hdwe.
It was quite useful and that tv station used it many times a day for 17
years
b4 it burnt to the ground in the later '90's. The shuttle used it
because it was
CMOS and immune to radiation levels that were rather quickly lethal to the
shuttle crew.
Nice walk down memory lane, thanks for the mention that triggered it.
I still have paper copies and tapes of that software on a high shelf here.
Cheers, Gene Heskett, CET.
--
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soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
Don't poison our oceans, interdict drugs at the src.
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