18 Dec
2008
18 Dec
'08
12:31 p.m.
Dave McGuire wrote:
On Wed, December 17, 2008 3:05 pm, Brent Hilpert wrote:
60's era ones yes, but by 1978 or earlier they were like this:
http://www.ssplprints.com/image.php?imgref=10240744
LED display, keypad input. A friend has one, still in use, but I haven't bugged
him to let me look inside it. Could have been done with an ASIC of course but
it would also have been a good candidate to have used some mask-programmed 1 or
2 chip micro such as the PPS-4/1.
It's a minor interest: earliest consumer items (aside from the obvious
calculators) to use embedded micros. The earliest I have seen so far is a
Sherwood FM tuner ca. 1977 that uses an RCA 1802 (e.g.
http://atlanta.craigslist.org/ele/927622156.html). Repaired a couple for a
friend but forgot to take exact chip dates.
There was a later PPS-4/1 single-chip version. I
don't know how popular
this
stuff was but I wonder if there aren't more PPS-4 systems buried in
equipment
and appliances from the period than is commonly known. (I have wondered,
for
example, what the 70's-era Amana Radarange microwave ovens used for
control.)
Umm...mechanical timers.