Christian_K:
- 100000bps would still be acceptably fast and offers 0% error - but does the windows com port driver accept this unusual baudrate without throwing an expection?
The ability to track your baudrate request depends on the driver and the underlying hardware. If you choose a TTL/USB driver/chip that properly document how baudrate is calculated, you will be able to control and limit the difference between sender and receiveer baudrate towards zero. Below is a link to an application note from FTDI that explains how this is calculated for their drivers. Another option may be an AVR/USB chip (such as the one used by UNO) where you can refer to the datasheet for exact information.