J
jasen
- Jan 1, 1970
- 0
I'd prefer a programmable logic part - the 4-digit counter is not
synchronous with the multiplexing logic for the display.
Back in 1972 I dealt with this problem by freezing the multipexing
clock until any
incoming count had rippled through the (asynchronous) counters, which
took up to 4usec. This wasn't an elegant solution. With a
microcontroller, I guess you'd rely on the interrupt system to capture
clock increments that occured at the wrong instant, and you'd keep your
interrupt handler short and quick to keep the maximum count rate
respectable.
easier to just use the built-in hardware counter,
AtTiny2313 has a 16 bit hardware counter, set the limit register to 10000
and you can have a hardware carry output.
loop that output back to the input for the other 16 bit counter and you could
drive 8 digits, but for the lack of enough I/O pins
the display, (which usually need only be fast enough for human perception)
can then be done in software.
Programmable logic offers true parallel processing, which can be a lot
tidier.
so do microcontrollers (to a limited extent)
Bye.
Jasen