Interrupt status flags Control register
| RX_FERR | Flag for RX Frame Error Interrupt. |
| RX_PAR | Flag for RX Parity Error interrupt |
| CTS_EV | Flag for CTS signal change interrupt (hardware flow control disabled) |
| RX_OV | Flag for RX FIFO Overrun interrupt |
| RX_THD | Flag for interrupt when RX FIFO reaches the number of bytes configured by the RXTHD field |
| TX_OB | Flag for interrupt when TX FIFO has one byte remaining |
| TX_HE | Flag for interrupt when TX FIFO is half empty |