(once more with the correct subject)


Right, I had no good reason for enabling interrupts.  I pasted in some usart
code to try to get something working fast and never expected interrupts to
occur so didn't pay that much attention to them.  It took me quite a
while to figure out what  was wrong with the program and to isolate
the problem to the setting those bits, but when I did, I wanted to
know exactly which ones were causing the problem.  And it turned out
it was all of them.

I accept your statement that a signal on the RX pin probably caused
the problem but why do both GIE and PEIE need to be set for the
unplanned interrupt to occur?

On Oct 22, 2007, at 2:06 PM, Don French wrote:
> For the record, the delay routine is not code that I wrote.  It is
> supplied with the CC5X compiler.  But it does work every time except
> the first time after setting all five of the enable bits I mentioned:
> Serial port enable (SPEN), Continuous receive enable (CREN),
> Peripheral interrupt enable (PEIE), Global interrupts enable (GIE),
> Recieve interrupts enable (RCIE).  If I omit setting any one of these,
> the delay works perfectly.
>
> My test program has no interrupt processing as it doesn't expect to
> receive any, but that may be a mistake.

If you have no interrupt processing, then why the heck are you
enabling interrupts?

With those five bits set, any noise on the RX pin will trigger an
interrupt (after a delay set by your baud rate setting).

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