The maximum clock frequency for the SC16C752BIBS,157 is 40 MHz.
To configure the UART for 9-bit data transmission, set the MCR[7] bit to '1' and the LCR[2] bit to '1'. This enables 9-bit data transmission with a 9th bit as a parity bit.
The XOFF and XON characters are used for software flow control. XOFF (usually 0x13) is sent by the receiver to the transmitter to request a pause in data transmission, and XON (usually 0x11) is sent by the receiver to the transmitter to resume data transmission.
To implement RTS/CTS flow control, connect the RTS output of the transmitter to the CTS input of the receiver. The transmitter will assert RTS when it is ready to transmit, and the receiver will assert CTS when it is ready to receive. The transmitter will only transmit when CTS is asserted.
The main difference between the SC16C752BIBS,157 and the SC16C752DIBS,157 is the operating voltage range. The SC16C752BIBS,157 operates from 2.5 V to 3.6 V, while the SC16C752DIBS,157 operates from 1.8 V to 3.6 V.