[sdiy] Top/Bottom Ten ICs

[Tom May]

Phil Macphail <philip.macphail at ntlworld.com> writes:

> > Yes, but how often did you use time sharing on a processor designed
> > for use in a home micro?
> 
> But that is the explanation for the whole architecture - the TMS9900
> was a single-chip implementation of an existing discrete CPU used in a
> multi-user system, and the 8-bit bus probably a cosequence of fitting
> into the available packages.

IIRC it had a 4-phase clock, they could have freed up three pins by
going to single phase :-)

This 9900 discussion has been interesting.  Years ago I had a job
working on a TI 990/10 minicomputer.  It was my first somewhat real
job.  The 990/10 had some kind of multi-user operating system and
whether it used a TMS9900 or some discrete version of the same
architecture I don't know, but from a software perspective I did like
the architecture.

My list of top ten ICs is based on what inspired me to learn more
about electronics over the years and got me where I am now:

Z80    coolest old-school 8-bit cpu, single-phase clock, dram refresh, . . .
7410   3-input NAND gate, functionally complete (LS preferred at the time)
7805   what else do I need to make this work?
7447   7-segment LED decoder/driver, very fun, and how do they do that?
7476   dual JK flip/flop, beyond combinational logic
7401   open collectors?  maybe I should learn about tranistors.
74125  mmm, tri-state
741    introduction to opamps
565    Craig Anderton used this for a ring modulator
3080   the mighty OTA, subject of extreme mystery to me for about a decade

Extra bonus IC:

68000  the world would be a better place . . .

And finally:

The 6-pin opto-isolators we would buy from Radio Shack in 1981.

Tom.