🚀 go-pugleaf

In article <1272@eplunix.UUCP>, raoul@eplunix.UUCP (Nico Garcia) writes:

> Hi. I have a panel display of BCD thumbwheels I'd like to decipher into
> binary: 4 or 5 decades of BCD to 12 or 16 bits of binary.  TI used to ...

Five decades would be tricky as the maximum of (decimal) 99999 exceeds the 
16-bit limit.

A standard approach uses a large number of Full Adders where e.g. the ouputs of 
the decades are wired accoring to the "weight" of the code. E.g. for the second 
decade the weight is 10, 20, 40, 80 respectively or 8+2, 16+4, 32+8 and 64+16.

Is that the approach that leads to 11 chips?

With 4 decades there's 4*4=16 inputs and 16 bits of output such it could be
done by taking two standard 64KB EPROMs. Writing a program for the code in the 
EPROMs is rather straightforward.

Succes, <kees>

Kees  van der Wal		       e-mail: J.C.vanderWal@research.ptt.nl