19 Jun
2007
19 Jun
'07
11:57 a.m.
woodelf wrote:
Dave McGuire wrote:
..flipping through IC Master '81:
- The 74S481 4-bit slice.
- Fairchild CMOS 470x series (4705 4-bit ALU/register slice).
- Motorola ECL MC10800 series (4-bit ALU slice)
- Siemens ECL SH100B480 4-bit slice
- Mustn't forget the 74181 & 74281 4 bit ALUs in the standard TTL series,
although I suppose some may argue because they don't contain the register portions.
Before bit-slice chips, the HP 2116 was constructed in 'bit-slice form' from
SSI: 4 boards plugged into the backplane are identical, each board containing
4 bits of the 16-bit ALU and main registers. I expect other SSI-era minis were
done this way. Were any of the early PDP-11's constructed this way, or did the
first PDP-11 use the 74181?
A weird chip I ran across recently in an early 80's protocol analyser is the
AMD 29116. The overview in IC Master calls it a
"16-bit Bipolar Microprocessor" but it only contains the ALU, registers, and
instruction register/decoding. It appears the program counter/sequencing have
to be provided externally, and it doesn't appear to be cascadeable so you
can't really call it a bit-slice.
Many, many machines were built in this way...I
only use the VAX-11/730
and DECsystem-2020 as examples because I have them sitting here.
Further, the Am2901 isn't the only bit-slice CPU around...there were
many others. Intel made at least one, I think it was the 3002.
That was a 2 bit bit slice. TI had a weird 4 bit slice. That is all
the ones I can think of.