SWRU455M February 2017 – October 2020 CC3120 , CC3120MOD , CC3130 , CC3135 , CC3135MOD , CC3220MOD , CC3220MODA , CC3220R , CC3220S , CC3220SF , CC3230S , CC3230SF , CC3235MODAS , CC3235MODASF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
The UART is a standard asynchronous serial communication that works between two entities and supports hardware flow control. In the UART interface, there is no Master/Slave relationship defined by the hardware, and each entity can send data to the other side independently in full duplex mode. The hardware flow control makes use of two hardware lines, RTS (Request to Send) and CTS (Clear to Send), to allow each side indicate to the other side if it is ready to handle data.
Figure 25-11 illustrates a typical UART setup.
The perspectives of the lines’ names further in this document are from the host to the SimpleLink device:
TX – used to send the UART serial data from the host to the CC31XX device
RX - used to send the UART serial data from the CC31XX device to the host
RTS - used to instruct the CC31XX device to stop sending data (host cannot handle more data)
CTS – used to instruct the host to stop sending data (the SimpleLink device cannot handle more data)