NRF52811-QCAA-R datasheet(394/444 Pages) NORDIC

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Peripherals

N-1

N-2

Figure 148: UARTE transmission

The UARTE transmitter will be in its lowest activity level, and consume the least amount of energy, when it

is stopped, i.e. before it is started via STARTTX or after it has been stopped via STOPTX and the TXSTOPPED

event has been generated. See POWER — Power supply on page 48 for more information about power

modes.

6.28.3 Reception

The UARTE receiver is started by triggering the STARTRX task. The UARTE receiver is using EasyDMA to

store incoming data in an RX buffer in RAM.

The RX buffer is located at the address specified in the RXD.PTR register. The RXD.PTR register is double-

buffered and it can be updated and prepared for the next STARTRX task immediately after the RXSTARTED

event is generated. The size of the RX buffer is specified in the RXD.MAXCNT register and the UARTE will

generate an ENDRX event when it has filled up the RX buffer, see UARTE reception on page 395.

For each byte received over the RXD line, an RXDRDY event will be generated. This event is likely to occur

before the corresponding data has been transferred to Data RAM.

The RXD.AMOUNT register can be queried following an ENDRX event to see how many new bytes have

been transferred to the RX buffer in RAM since the previous ENDRX event.

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NRF52811-QCAA-R Datasheet(PDF) 394 Page - Nordic Semiconductor