In article: <9412100210.aa18243@punt.demon.co.uk> ssmith@csuvax1.murdoch.edu.au
writes:
> The other day I was looking through some old Scientific American magazines.
> The September 1977 issue (special issue on Microelectronics) has a full-page
> ad from General Instrument Corporation advertising a range of microcontrollers
> including several PICs. This confirmed what I had been told by others - that
> Arizona Microchip acquired the PIC design from GI.

This is more tha just a story...see below.

>
> Does anyone know the full story? How old is the PIC architecture? What happene
d
> to GI?
>

Back in 1965, GI formed a Microelectronics Division, and indeed used
this division to generate some of the earliest viable EPROM and EEPROM
memory architectures. As you may be aware, the GI Microelectronucs
Division were also responsible for a wide variety of digital and analog
functions, in the AY3-xxxx and AY5-xxxx families.

GI also generated a 16 bit microprocessor, called the CP1600, in the
early 70s. This was a reasonable microprocessor, but not particularly
good at handling i/os. For some very specific applications where good
i/o handling was needed, GI designed a Peripheral Interface Controller
(or PIC for short), in around 1975. It was designed to be very fast,
since it was i/o handling for a 16 bit machine, but didn't need a huge
amount of functionality, so its microcoded instruction set was small.
Hopefully, you can see what's coming....yes, the architecture designed
in '75 is substantially the PIC16C5x architecure today. Granted, the
1975 version was manufactured in NMOS, and was only available in masked
ROM versions, but still a good little uC. The market, however, didn't
particularly think so, and the PIC remained designed in at a handful of
large customers only.

During the early 80s, GI took a long hard look at their business, and
restructured, leaving them to concentrate on their core activities,
which is essentially power semiconductors. Indeed they are still doing
this very successfully now. GI Microelectronics Division became GI
Microelectronics Inc (a wholly owned subsidiary), which in 85 was
finally sold to venture capital investors, including the fab in
Chandler, Arizona.  The venture capital people
took a long hard look at the products in the business, and got rid of
most of it - all the AY3- and AY5- parts and a whole bunch of other
stuff, leaving the core business of the PIC and the serial and parallel
EEPROMs and the parallel EPROMs. A decision was taken to restart the
new company, named Arizona Microchip Technology, with embedded control
as its differentiator from the rest of the pack.

As part of this strategy, the PIC165x NMOS family was redesigned to use
one of the other things that the fledgling company was good at, i.e.
EPROM - the concept of the CMOS based, OTP and eraseable EPROM program
memory PIC16C5x family was born.

Does this answer your questions?

Alex R. Baker - Field Apps Engineer Ph: +44 628 851077  Car: +44 831 494921
Arizona Microchip Technology        Fx: +44 628 850259  Email: alex@microchp.dem
on.co.uk
ANY VIEWS EXPRESSED HERE ARE MINE AND DO NOT NECESSARILY REPRESENT THOSE OF MY E
MPLOYER