The example below shows how to assign channel 5 to embed RSSI on a DragonLink RC receiver:
If there is an existing RC receiver connection to your autopilot, no additional wiring is required for using embedded RSSI:
See your respective system’s user manual for reference. Usually, these systems use a GUI to assign RSSI to a dedicated channel slot on your RC receiver, or have it set to a standard channel by default. As per ArduPilot default channels 1-4 are used as input for primary control (roll, pitch, throttle, yaw), any channel number above 4 can be used to embed RSSI. Most UHF type RC systems like EZUHF, OpenLRS, Crossfire or DragonLink support embedding RSSI into a dedicated channel within this collective / sum signal stream. It is common practice to feed all RC channels from your RC receiver to your autopilot using a cPPM or sBus type sum signal on a single signal wire. RSSI embedded in a collective PPM / sum signal’s channel ¶ On boards with IOMCU these are the AUX pins that can be used as PWM output by default or alternatively set to be used as GPIO. RSSI_ANA_PIN Specifies the GPIO pin to read PWM type RSSI from. RSSI_TYPE = 4 PWM type RSSI fed to a dedicated GPIO pin Scaled internally, no further adjustments required. RSSI_TYPE = 3 digital receiver protocols’ signal quality or dropped packets information (SUMD / ST24 /FPort) RSSI_CHAN_LOW PWM value the radio receiver will output when the signal is the weakest. RSSI_CHAN_HIGH PWM value the radio receiver will output when the signal is the strongest. RSSI_CHANNEL Channel number the radio receiver will use to embed RSSI if collective / sum signal is used (channel 5 and up). RSSI_TYPE = 2 PWM Channel type RSSI embedded in a collective PPM / sum signal (sBus) RSSI_PIN_LOW voltage received on the RSSI_ANA_PIN when the signal is the weakest. RSSI_PIN_HIGH voltage received on the RSSI_ANA_PIN when the signal is the strongest. This parameter defaults to the correct pin number on most boards when using current chibios firmware. RSSI_ANA_PIN specifies the pin used to read RSSI voltage. RSSI_TYPE = 1 Analog voltage type RSSI fed to a dedicated pin