Computer Taxonomy

From: Allison J Parent <allisonp_at_world.std.com>
Date: Fri May 1 11:24:45 1998

<However, some of the very simple controllers in, e.g., lawn sprinkler
<timers, etc. could possibly be classified as just programmable logic
<elements -not really "computers". I can imagine a simple Epson or whateve
<clock chip and a small programmable array logic (PAL) chip of some low co
<type being setup with very simple I/O to act as the "programmable" contro
<in those types of equipment. Or, rather, an application specific
<integrated circuit or ASIC could be specially designed and fabricated to
<replace all of this if production quantities are in the many thousands.
<Still, no microprocessor chip though.

This is not true, many VCRs have version of the NEC ucom75 chips, cmos
single chip microprocessor(512b-2kb rom, 128nybbles of ram(max) lots of
IO for various purposes). The TI1000 series were used in games and
Microwave ovens. Most of the things like lawn spriklers controllers are
chips like 8048/9, PIC, or other cheap in volume mask rom
single chips micros.

The list can go on but true ASICs are expensive to develope and limited
in scope. There are an abundance of small very low cost single chip
micros that can do tasks like those described.

FYI what does seperate most of these from the general taxonomic classes
is that the "program" is inaccessable on most of these so altering it
is unlikely to impossible.

Allison
Received on Fri May 01 1998 - 11:24:45 BST