Detailed Description

nRF24L01+ radio driver (DETWS_ENABLE_NRF24) - Nordic 2.4 GHz over SPI.

A radio driver plugin for the gateway (DETWS_ENABLE_GATEWAY): cheap point-to-multipoint 2.4 GHz sensor links bridged to the web stack. Unlike the SX127x (plain register read/write), the nRF24L01+ speaks an SPI command protocol (each transaction is a command byte + data, and every command returns the STATUS register) and needs a separate CE pin to key RX/TX - so the driver runs over an nrf_bus that carries a full-duplex SPI transfer plus a CE-set callback. That is the only board-specific code.

The nRF24 does its own hardware addressing (5-byte pipe addresses), so a received frame's "source" is the pipe number it arrived on - there is no in-payload header and therefore no separate codec. It uses a static payload width (DETWS_NRF24_PAYLOAD): every frame is that many bytes (a short send is zero-padded). Bridge received payloads northbound with det_gw_uplink(port, pipe, payload, width, 0). The register/command protocol is host-testable against a mock; the RF link needs the module.

Author: Douglas Quigg (dstroy0)

Date: 2026

Definition in file nrf24.h.