On Apr 22, 1:57, Tony Duell wrote:
> Jack Peacock wrote:
> > 'No, I can do it with a normal 16 pin TTL chip that doesn't have to go
> > in a programmer first'. So, what was the chip ?
> >
> > 74LS138, 1 of 8 decoder, the three inputs go to A, B, C, all 8
> > possibilities decoded on the outputs.
>
> Alas not.. I didn't want the 8 separate combinations of the 3 input
> variables - I wanted a single output that was a complex function of them
> - something like A.C + A.B/ + A/.C/.B or something...
I thought of that too. Then you might be able to do it with an AOI package,
but I'd use a 156, which is a demultiplexer/decoder but with open-collector
outputs, which I'd wire-AND.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
Received on Wed Apr 22 1998 - 10:10:46 BST