UARTE double-buffered

The sample demonstrates a functionality of the nrfx_uarte driver utilizing double-buffering feature.

Requirements

The sample supports the following development kits:

Board	Support
nrf52dk_nrf52832	No
nrf52833dk_nrf52833	Yes
nrf52840dk_nrf52840	Yes
nrf5340dk_nrf5340	Yes
nrf54l15dk_nrf54l15	Yes
nrf9160dk_nrf9160	Yes

Overview

Application initializes the nrfx_uarte driver, and using UARTE instance sends a specified message stored in m_tx_buffer. The same instance of UARTE is configured to receive the message. To perform this operation, different buffers are used, and data is transferred as follows:

m_tx_buffer -> m_rx_buffers

To show the double-buffering feature the data is written to different buffers in the m_rx_buffers structure. The uarte_handler() is executed with relevant log messages.

‍For more information, see UARTE driver - nrfx documentation.

Wiring

To run the sample correctly, connect pins as follows:

LOOPBACK_PIN_1A with LOOPBACK_PIN_1B.

‍Refer to pin definitions in common/nrfx_example.h.

You should monitor the output from the board to check if it is as expected.

Building and running

To run this sample, build it for the appropriate board and then flash it as per instructions in Building and running section.

Sample output

You should see the following output:

- "Starting nrfx_uarte RX double-buffered example."
- "Content of TX buffer: Nordic Semiconductor nRF"
- "................................"
- "RX buffer1 - addr: (.*) | content:"
- "RX buffer2 - addr: (.*) | content:"
- "RX buffer3 - addr: (.*) | content:"
- "................................"
- "--> TX done"
- "--> Bytes transfered: 25"
- "................................"
- "RX buffer1 - addr: (.*) | content: Nordic"
- "RX buffer2 - addr: (.*) | content:  nRF"
- "RX buffer3 - addr: (.*) | content:  Secmiconductor"
- "................................"

‍(.*) stands for memory address