12 Mar
2019
12 Mar
'19
5:23 p.m.
On Mar 12, 2019, at 5:51 PM, Murray McCullough via
cctalk <cctalk at classiccmp.org> wrote:
...
I?ve written in my book on the History of the Microcomputer a history of
the processing chip as the timeline follows an approximation of:
Late *1950*s ? patent on integrated circuit by Texas Instruments
*1950*s to *1960*s ? move from vacuum tubes to TTL technology
programs/functions in ROM
You turned two steps into one: vacuum tubes to discrete transistors (1958 to mid 1960s)
then transistors to TTL SSI ICs (1965-1975 or so), then CMOS and LSI. With some detours
-- some high end computers using ECL, for example.
Also, when you said ROM you probably meant semiconductor ROM (mask ROM); earlier there was
core ROM, invented (two variations, one in the USA and one in Holland, apparently
independently) around 1957 and first appearing in a commercial computer in the 1958
Electrologica X1.
paul