On Fri, 23 Nov 2001 15:40:10 +0100, you wrote:

>
>Note that there is no law that you must send the bits in a loop: with =
some
>calculation (and enough code space) you can unroll the loop and be up to=
 1
>instruction accurate.
>

True, but it doesn't make much difference whether you write your code
as a loop or unroll it. Either way, the baud rate cannot be made any
more accurate than the 1 instruction time granularity. Whether your 1
instruction accuracy is in a loop or in-line code, the instruction
time determines how close you can get to the desired baud rate.

Using a 10 MHz or 20 MHz crystal, by definition, introduces some
amount of baud rate error.=20

Using the 'oddball' 9.216 MHz crystal (or 18.432 MHz as someone else
suggested. How did I forget that one?) will allow you to minimize the
error.

Regards, Bob

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