In article , SWbeginner
writes:

This would be great for me but can it work with LED's. I haven't work with
LCD displays before and don't know which one works.

There are several LCD display units available commercially with the
LCD (typically 2 x 16 character rows), drivers and temporary memory,
and optional backlights. They are driven by ASCII coded character
digital byte-parallel input assemblies. PIC and Atmel based counters
can output ASCII according to count plus including controllable legends
for whatever purpose, all under the microcontroller internal program.

LEDs are fine for bright displays, good for viewing out of the corner of
the eye to note changes when working on something. Microcontrollers
could be reprogrammed to output sequential 7-bar segment signals for
external temporary storage, such as a latch-decoder-driver IC for one
decade's LED. LEDs are also relative power hogs from the local DC
supply compared to the entire LCD assembly (8 digits will take around
0.6 A maximum at 5 VDC to light 8 LEDs). LCD power drain is in the
microwatt range, the drivers of an assembly taking most of the DC
power. Low power demand is the major reason for using LCDs in
small-battery watches and radio clocks.

LED readout is very legacy in digital circuitry. Many-digit LCD
assemblies aren't so common and appear strange because they
haven't been as widely used for as long a time.


You might try Francesco Morgantini's (IK3OIL) PIC freq counter. It's
based on a 16f84 and he will email you the hex code if you request it.
It will run to approx 45 MHz as is and up to 1.5 GHz with a simple
add on prescaler. He has divide functions built in the program (
divide by 10/32/64) and he has also include IF offset if you want to
use the counter as a freq readout. I've etched about 40 boards for
local hams here and every one that has been built has worked without
fail. Total cost has been in the neighborhood of $35.00 including the
prescaler but excluding enclosure. If you want a copy of the circuit
board layout with prescaler, just email me at ww2742 at dragonbbs.com.
As for accuracy, I just adjusted one today for another local ham at
it was within 200 Hz at 440 MHz using a recently calibrated IFR-1200
for a source - that was close enough for me.

Here's his website URL:
http://digilander.libero.it/ik3oil/menu_eng.htm

I will suggest perusing the www.aade.com website to see the counters
available there. Some are available in kit form and they are simple and
elegant, include an LCD assembly for readout. All you need do is hook
up a DC power source and check the timebase against WWV.

Otherwise there are a surprisingly large number of websites concerning
PIC and Atmel based microcontroller counters along with associated
microcontroller program source listings. Any search will turn up dozens
of hits. Modifying the existing programs might take up more time than
you would imagine unless you have lots of Assembler coding
experience.

Len Anderson
retired (from regular hours) electronic engineer person