What is the difference of UART coding between high speed and low speed?

[Henry]

The UART coding between high speed and low speed is almost the same.
First, we must know the only difference of UART hardware between high speed and low speed is buffer length.
The buffer length is 64 bytes for high speed, but 16 bytes for low speed.
Also, user must select good threshold for receive buffer to produce RDA interrupt or RTS signal for high speed or low speed limits.