18 Dec
2006
18 Dec
'06
8:41 p.m.
Cleaning out things and came across 40+ tubes
(24/tube) of TTL 5400
Quad Nand Gates (Mil version of the 7400). Free for postage.
Here's your chance to build your computer from scratch :oD
CRC
'Tis all gone...
CRC
2 Jan
2 Jan
9:39 a.m.
CRC wrote:
So what computer got built?
For my final post -- About 20 TTL packages ( 80 2 input nand gates )
are needed for a simple 1 bit , bit slice PCB. XOR gates, Flip/flops
and muiltiplexers sure take up several packages.
Cleaning out
things and came across 40+ tubes (24/tube) of TTL 5400
Quad Nand Gates (Mil version of the 7400). Free for postage.
Here's your chance to build your computer from scratch :oD
CRC
'Tis all gone...
CRC 
2:07 p.m.
For my final post -- About 20 TTL packages ( 80 2
input nand gates )
are needed for a simple 1 bit , bit slice PCB. XOR gates, Flip/flops
and muiltiplexers sure take up several packages.
You can make a 2-input XOR gate from 4 NANDs (a single 7400). Ditto a
2-input single-bit mux. And of course a pair of SR flip-flops take up a
single 7400...
Making a JK or equivalent would be a few pacakges, though. I've not
worked it out, but I think a master-slave JK flip-flop is 3 or 4 7400s.
-tony
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