AMD bit-slice machines

[Tony Duell]

> IIRC the Three Rivers PERQ was also a 2901 based design.

Not any PERQ that I've seen (and I think I've seen all models). 

The classic PERQs (1, 1a, 2T1, 2T2, 2T4) used 74S181 ALUs and 256 nybble 
RAMs for the registers (yes, 256 CPU registers).

The sequencer was an AMD 2910, which, of curse, is from the same family 
as the 2901. But the 2910 is not IMHO a true 'slice' in that it can't be 
extended to <n> bits. It's a 12 bit microcode sequencer (and all PERQs 
apart from the 1 had 16K of control store, so they had to extend the 
sequener address by a circuit kmown to all PERQ fanatics as the '2 bit 
kludge', pun totally intentional). The PERQ ethernet interface and hard 
disk cotnrollers also used 2910 sequencers with PROMs as the control store.

The PERQ 3a (AGW3300) was a 68020-based machine. The graphics processor 
used a pair of 29116 data path chips (one to calculate addresses, one to 
do the data processing) along with a very simple sequencer built from TTL.

-tony