> Why XT with an external clock?  The datasheet has not
> specifically stated this, and indicates that LP is fine for
> 1.544Mhz (DS30221B, page 89).  Not disputing, but asking for
> more info as to why XT.  BTW, tried XT and that did not solve
> the problem.

Too bad you didn't indicate what section you found this spec in on page 89.
I am using "PIC16F87x Data Sheet", DS30292C, which I think is the latest
that covers the 16F872 you are using.  See Table 15-1 "External Clock Timing
Requirements" on page 162.  The maximum external CLKIN frequency is shown as
200KHz for LP mode, and 4MHz for XT mode.

I am curious what you saw that contradicts this.  Can you find the same
reference in DS30292C or anything that supercedes it?


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