Defect in Intel 8254 ..?

I built some hw construction with Intel 8254 Interval Timer some years ago and
it seemed one of the counters could not count to certain values or in certain
modes. Not mentioned in the datasheet at all.
Is there a known defect with Intel 8254 ..?

 

I'm a little fuzzy, but yes, I had these problems (22 years ago!).
Something to do with a) missing the first count when used as a
counter, and b) not being able to divide by 2(??).

Also, different in these respects when compared to the 8253, and
something hinky lurks in my memory about the 82c54 being slightly
different again...

Anyway, I figured out workarounds that allowed me to use the 82c54
such as it was, after a great deal of cursing! So, it's possible.

HTH,
James Arthur

 

Compare to the AMD 9513, which has various useful additional features *not*
described in the data sheets?

In many ways life became much more interesting when FPGAs/CPLDs became cheap
and you could build any "weird" sort of counter/timer without having to play
funny games with the standard ICs. (I remember a co-worker commenting that
the Intel 8096 microcontroller had a timer/counter that was *exactly* what you
wanted if you were building a controller for the fuel injection on a V8
engine! If not, well... it was nowhere near as useful...)

 

Several. Check out
http://www.intel.com/design/archives/periphrl/docs/7178.htm.

 

Link doesn't work..

 

It does for me. Remove the final period.

Anno

 

Excellent source. Thanks!

--James Arthur

 

You might have to strip the angle bracket(s) at the front and the
period at the end. (when I do that, the link works for me.)

Good Luck!
Rich