INAV RSSI Signal Strength Configuration

Introduction

RSSI (Received Signal Strength Indicator) is an important parameter for measuring wireless signal strength. It helps pilots determine if the aircraft is about to go beyond the control range or is experiencing RF interference.
INAV supports the following three common RSSI input methods:

1. RSSI through a PPM channel
2. RSSI through parallel PWM channels
3. RSSI via ADC from a PPM RC receiver with RSSI output

RSSI through PPM

1. Set a spare channel on the receiver to output the RSSI value (e.g., CH9).
2. Connect the receiver to the flight controller and ensure the signal from this channel is recognized by the FC.
3. Set the RSSI channel via CLI command, indicating that channel 9 will be used as the RSSI input source:

set rssi_channel = 9
save

Some systems (e.g., EZUHF) output an inverted RSSI signal (i.e., 0 means full signal, 100 means signal lost), which will cause incorrect readings. The default setting should be "0" (100 = full signal / 0 = signal lost).
If you find that the RSSI values are inverted, you can use the following CLI command to invert the RSSI range:

set rssi_min = 100
set rssi_max = 0
save

RSSI through Parallel PWM Channels

After connecting the RSSI signal to any PWM input channel, its configuration is identical to RSSI configuration in PPM mode.
Connect the receiver's RSSI output signal wire to an available PWM input channel on the flight controller (e.g., CH8).
In the flight controller CLI, set this channel as the RSSI input channel, for example:

set rssi_channel = 8
save

If the RSSI signal used is inverted (i.e., 0 means good signal, 100 means poor signal), it can be corrected with the following command:

set rssi_min = 100
set rssi_max = 0
save

After completing the connection, it is recommended to check the RSSI values on the Receiver page of a ground control station (such as INAV Configurator) to see if they change with distance, in order to verify the connection is correct.
————This article is referenced from the official INAV website: https://github.com/iNavFlight/inav/blob/master/docs/Rssi.md