Strange behavior qtserialport on linux with custom baud rate

Brian_l

Have an app that communicates through serial interface at 8192 baud rate. When setting baud rate in the app I get this error:
Baud rate of serial port /dev/ttyUSB0 is set to 8193 instead of 8192: divisor 2929.687500 unsupported

even though 8193 is well within the range that would be acceptable for communicating with device.
If I set the baud rate to 8193 in the app, I still get the error:
Baud rate of serial port /dev/ttyUSB0 is set to 8193 instead of 8193: divisor 2929.329834 unsupported

It works flawlessly under windows.

The base baud is 24000000 and the divisor should be 2929, but it's setting the divisor as a float. Not sure what's going on here, or why it's failing this check. Any input would be appreciated

Version of QT is 5.5
serial device is ftdi

kuzulis

The base baud is 24000000 and the divisor should be 2929

No,

24000000 / 8192 = 2929.6875
24000000 / 8193 = 2929.3299157817649212742585133651

Warning about there is no integer divider for the desired speed, and the near divider will be set (2929). So, speed will be 24000000 / 2929 = 8193.9228405599180607715944008194 baud.

Brian_l

thanks, that was really helpful