From: "petrus bitbyter"
Subject: Re: ? Binary to BCD conversion chip ?
X-Newsreader: Microsoft Outlook Express 5.50.4807.1700
Date: Fri, 06 Dec 2002 19:36:55 GMT
NNTP-Posting-Date: Fri, 06 Dec 2002 20:36:55 MET
Organization: chello broadband
> Dear friends-
> I have a related question: Does anyone kow of a good way to convert 12
> bit binary to bcd? This comes after a 12 bit ripple counter that will
> count to 4096 in one second.
Your question is not only related, it's (almost) the same. So all answers
you have for an eight bit conversion will do (or not) for the twelve bits
conversion as well. Assuming your counter is given and the need for BCD is
given as well, the easiest way is programming a 16 bits EPROM. You can use
two 8 bits EPROMs as well. It will require some space but don't forget you
should have needed eight 74LS185 chips to do the trick. (An eight bits
conversion requires only three of them.)
You can use counters with some control logic. Chipcount and conversion time
may become a problem.
A microcontroller will also do the job, but you will need a big one as you
need twentyeight i/o-pins. (Of course you can multiplex i/o but at the
expence of some extra buffer/registers.) If you want to convert fast, you
will have to use table- lookup wich will require the same amount of memory
as the EPROMs mentioned earlier.