SPRUHZ7K August 2015 – April 2024 AM5706 , AM5708 , AM5716 , AM5718 , AM5718-HIREL
When the receiver FIFO is enabled in the FIFO control register (via setting the PRUSS_UART_INTERRUPT_IDENTIFICATION_REGISTER_FIFO_CONTROL_REGISTER [0] IPEND_FIFOEN to 0b1) and the receiver interrupts are disabled in the interrupt enable register (PRUSS_UART_INTERRUPT_ENABLE_REGISTER), the poll mode is selected for the receiver FIFO. Similarly, when the transmitter FIFO is enabled via setting the same bit (PRUSS_UART_INTERRUPT_IDENTIFICATION_REGISTER_FIFO_CONTROL_REGISTER [0] IPEND_FIFOEN to 0b1) and the transmitter interrupts are disabled, the transmitted FIFO is in the poll mode. In the poll mode, the CPU detects events by checking bits in the line status register - PRUSS_UART_LINE_STATUS_REGISTER:
Also, in the FIFO poll mode: