This has nothing to do with any operating system. Just a general question regarding the goog old rs232.

Lets say you have a synchronous RS232 tranmission interface channel available to you. The channel is set for 19200 bits per second. You have an asynchronous RS232 data with the 3 pins (TXD, RXD, and GND) at 4800 bps. The questions is, can you send this asynchronous data over that synchronous channel? If so, what problems to look for? There is nothing else avialble, no IP, no enthernet, no USB, no nothing. That is what needs to be sent, that is what is available. Thats it.

I am not sure what you are doing but if you enter the following search string into Google, you will get several hits - one of which may be what you are looking for.

asynchronous data over synchronous channel