ajp166 wrote:
>
> Tony,
>
> Faster as in is sub 150ns are fairly common and cheap. Whats
> problemtic is that the ALU must do about 8-16 different operations
> so that would be at least a 512kN part or larger.
>
> Also 74(ALS,F,AS)381 in the 16 bit or wider range would be hard
> pressed to do better than 50ns even with carry lookahead.
>
Having a F-data sheet here lets check that 32 bit alu.
Sel to ~PG 15 ns 74F381
~PG to ~PG 12 ns 74F182
~PG to CY 9 ns 74F182
cy to F 13 ns 74F382
-----------------------
49 ns
Yep close. Ben Franchuk.
--
Standard Disclaimer : 97% speculation 2% bad grammar 1% facts.
"Pre-historic Cpu's" http://www.jetnet.ab.ca/users/bfranchuk
Received on Mon Nov 05 2001 - 18:13:20 GMT