Art,

Regarding your remark...

Code:
"Next time I do any LED clock I’d like to try a centi and millisecond display HH:MM:SS:cc:mm!"
You can certainly do this with very few changes to DT's Elapsed_INT file, as I am positive you already know.

I have already done this once before for a project that I needed to display sub-second time.

I had created an ElapedDemo program and modified Darrel's original "Elapsed_INT.bas" file appropriately.

I also took the time to continue to modify the file to incorporate some of the changes he did for his DT_INT-18.bas file for v1.2.
He did away with hard coded TimerConst values for the different OSC values and replaced it with a compile-time calculation instead.
He also did away with the TIMER1 prescaler and implemented a SW postscaler instead for frequencies above 20MHz.

All very cool ideas. Sure do miss DT and his wisdom.

Plus, I added a change of convenience that others might find useful to quickly change the interrupt period at compile time.

I will comment the changes, clean up the code and give it a good test.
Once I am done, maybe tomorrow or the next day, I will post it all here in a zip file.

Cheers.