Received Signal Strength Indication (RSSI)¶
This article shows how to get the Received Signal Strength Indication (RSSI) from an FrSky receiver to APM.
Provide RSSI from FrSky receiver to APM.¶
- Select the input pin with the RSSI_PIN parameter.
- However some of receivers such as FrSky D8R-XP output 0 - 3.3 V.
- For that reason I’ve added new parameter: RSSI_RANGE.
- This was also a requested issue previously: https://github.com/ArduPilot/ardupilot/issues/648
- When the RSSI_RANGE parameter is set to your radio’s maximum RSSI voltage the RSSI rxrssi is shown in the range 0-100.
- The ability to set the RSSI_RANGE parameter has been added to Mission Planner in the Full Parameter List:
Complete System with RSSI addition¶
A 4.7k resistor and 10uF capacitor are used to filter out the pulses from the receiver’s RSSI output.
RSSI embedded in PWM from UHF systems (Pixhawk)¶
Both EZ-UHF and OpenLRS have the option of embedding RSSI into a PWM channel, saving you from having to add filters, etc. You can use any channel from channel 5 and up, but keeping the on channel 9 or above will keep your regular servo channels free.
Set up your UHF system to embed the RSSI into the desired channel and then change the following parameters:
- RSSI_ANA_PIN : 103
- RSSI_TYPE : 2
- RSSI_CHANNEL : Your selected channel from above.
Developed and illustrated by Lukasz - Thank You - Hope this helps.