>>>>> "Jim" == Jim Paris <jim@xxxxxxxx> writes:
Jim> Uwe Bonnes wrote:
>> >>>>> "Jim" == Jim Paris <jim@xxxxxxxx> writes:
>>
>> ... >> results. However with the RS232 pattern you can't easily
>> measure >> exact frequency with the scope. ^^^^^
Jim> If you send a continuous string of UUUUU then you'll see the base
Jim> frequency as a simple square wave.
>> But the square wave is disturbed by the start/stop bits and the
>> turnaround between bytes. So you can estimate the frequency, but not
>> measure exact.
Jim> If you're using 8 data bits, no parity, and 1 stop bit, it'll be an
Jim> exact undisturbed square wave. Try it, you'll see :) The
Jim> turnaround between bytes will be zero as long as you don't let the
Jim> FTDI buffer underflow.
Okay,
the patches sent now make examples/serial_test.c explicit set the line
parameters to 8 data bits, no parity, and 1 stop bit.
Could people in doubt about the pending changes in baudrate calculation
please best try themself to set different baudrates and measure the
resulting frequencies or at least tell me what baudrates they have doubts
so I can test?
--
Uwe Bonnes bon@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------
--
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