15 Oct
2001
15 Oct
'01
10:47 a.m.
From: Iggy Drougge <optimus(a)canit.se>
standard
Ahh, the
74LS181s are ALUs, as is the 'F582. Interesting that they
used both. I'm curious...what kind of processor is this?
Am I the only one who finds it a bit perverse that there are 74xxx TTL circuits for such complex functions as ALUs? I
thought that the way
to go
would be to construct it out of simpler TTL circuits,
such as all the
740x
gates, not buying it as a package. I suppose I'm
not used to the concept
of
single 74xxx circuits carrying out such complex tasks.
It was the second generation before really complex LSI actually the '181
was
likely the highest gate count part in the class before the TI bit slices
(74881-884).
It's also very old but still a handy part as it does all the standard
arithmetic ops
and logical ones too. The ALU core of the 2901 is basically the 74181.
Allison