Receive Operation

The following figures show the waveforms when reading data from the UART controller.

As shown in the following figure, when baud_x16_ce goes high, the rx_data_valid flag goes high on next clock cycle. When the rx_data_valid flag is high, the rx_data is valid. The rx_busy status is low after receiving the stop bit and it is not affected by the baud_x16_ce signal.

Figure 1. Normal Receive Operation Waveform

When rx_error goes high, there is a transmission frame error. The rx_data_valid signal goes low to prevent incorrect data reads. The rx_error status goes low on the next rx_data byte.

Figure 2. Receive Error Waveform

When there is a parity error, rx_parity_error is set to high. The rx_parity_error goes low on the next rx_data byte.

Figure 3. Parity Error Waveform