4 Nov
2011
4 Nov
'11
9:07 p.m.
On 2011 Nov 4, at 7:07 PM, Eric Smith wrote:
Chuck Guzis wrote:
The CD40181 (and 40182) is mentioned in some RCA COS/MOS databooks
National also had a parallel series of CMOS
chips, with 4000
equivalents, the MM56xx series.
Wow, never heard of those. They had MM74Cxxx parts, which were
functionally equivalent to the other 74xx parts but with CD4000
equivalent electrical performance and timing.
Did anyone actually use a 4581 ALU in anything?
I've always
wondered if anyone built up a CPU from 4000 CMOS...
RCA had a bit-slice part in one of their 1970s COSMOS databooks,
with an app note in the back, but I've never been able to find that
particular COSMOS databook again, so if it went into production at
all it must not have lasted very long. My recollection is that it
was not as fancy as the Am2901. from the 70s.
Exactly what the name suggests: a
CMOS version of the 74181 4-bit ALU.
RCA did make some CMOS parts intended for building a
DSP processor.
I think I've got a slim "user manual" for them somewhere. Intended
for military applications.
Fairchild made some funky bit-slice ALU, register stack, etc.,
devices in the 70s (I think we have spoken of them here before).