Networking and communication with Nordic NRF52 devices, NRF24L01 & Arduino
Opening up new possibilities
So I recently created a new library (nrf_to_nrf) to communicate with NRF24L01 devices with the new NRF52x devices like the XIAO BLE SENSE 52840 sent to me by Seeed Studio. These devices open up some new possibilities as far as networking go and can be put to use in many different applications.
For example, the XIAO Sense 52840 has an on-board Gyro & Accelerometer making it useful for things like simple quadcopters, drones etc, and if used in combination with a high power NRF24-based transmitter, long distance control can be achieved with this tiny device. It is also very much suitable for Audio transmission and reception, allowing full-duplex audio transmission and reception at 1Mbps (using the ACK-Payload functionality) of the radio devices.
In contrast to the NRF24L01 which has 6 addressable pipes and can transmit up to 32-byte payloads, the NRF52x devices have 8 addressable pipes and can transmit up to 127-byte payloads. This opens up things quite a bit when it comes to networking these devices, allowing mixed NRF24L01 and NRF52 networks, and when NRF52x devices are solely used, expands the number of devices in RF24Network and RF24Mesh networks and the maximum transmission sizes. The NRF52x devices also have on-board encryption capabilities, enabled in nrf_to_nrf, so users can now create encrypted networks and communications scenarios.
I really like the NRF52x devices, specifically this little XIAO board, there are no pins to connect to the radio, and no issues with power supplies etc. I recently also updated the Auto Analog Audio library I created to support recording on these devices as well, making it possible to transmit audio over radio link using that library in combination with the nrf_to_nrf library. The code is still in its initial phases, without full functionality yet.
Modifications required to use the full capabilities of NRF52 only networks:
RF24 layer: Set the maximum payload size. Up to 125 with CRC disabled or 123 with 16-bit CRC. Use radio.setPayloadSize(123); or radio.enableDynamicPayloads(123);
RF24Network: Open RF24Network.h and set MAX_FRAME_SIZE to 111, Open RF24Network_config.h and set NUM_PIPES to 8
RF24Mesh: Open RF24Mesh_config.h and set MESH_MAX_CHILDREN to 6