I have made non-integral baud rates and timings by dynamically changing a
divisor while the timer runs. For example, if you reload a counter with 100
two times out of three and with 101 one time out of three, you will get a
timer result "average" that is 100.3333 clocks. I have made baud rate
generators that make baud rate clocks that everyone said were impossible! You
get jitter, of course, but that may be acceptable depending on the
application.

In the case you are asking about, is it critical that every interrupt be
exactly 46.27us, or just that they average out to that rate?

Chris

-----Original Message-----
From: pic microcontroller discussion list
[mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Jinx
Sent: Tuesday, July 29, 2003 7:01 PM
To: PICLIST@MITVMA.MIT.EDU
Subject: Re: [PIC]: how to generate 46.27 us interrupt


If you can de-tune an 11.0592MHz crystal (which is commonly
available) by just 0.05% you could get what you want with a
re-load of 128

1000000 / ( (11059200 / 4) / 128) = 46.2963us

1000000 / ( (11065476 / 4) / 128) = 46.2700us

But I don't know if a crystal will stretch that far - anyone ???

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