The I/O signals of the two UART controllers in the PS can be connected together. In this mode, the RxD and CTS input signals from one controller are connected to the TxD and RTS output signals of the other UART controller by setting the iou_slcr.MIO_LOOPBACK [UA0_LOOP_UA1] bit = 1. The other flow control signals are not connected. This UART-to-UART connection occurs regardless of the MIO-EMIO programming.