Telemetry
Telemetry is information sent back to your RC transmitter via the RC data link. For example, telemetry allows for your RC transmitter to read out your main battery voltage or RSSI. For telemetry to work your RC receiver and transmitter must support it. The specific data that Betaflight will send via telemetry depends on the telemetry protocol being used. For example, Smartport will send a certain set of information while Crossfire will send another set.
Crossfire protocol / CRSF
Here is the set of telemetry fields send via the Crossfire protocol.
| Datapoint | Description | Data unit | Data Source Id | SubId |
|---|---|---|---|---|
| 1RSS | Uplink - received signal strength antenna 1 (RSSI) | db | LINK ID | 0 |
| 2RSS | Uplink - received signal strength antenna 2 (RSSI) | db | LINK ID | 1 |
| RQLY | Uplink - link quality (valid packets) | % | LINK ID | 2 |
| RSNR | Uplink - signal-to-noise ratio | db | LINK ID | 3 |
| ANT | Antenna | raw | LINK ID | 4 |
| RFMD | Uplink - update rate; 0 = 4Hz; 1 = 50Hz; 2 = 150Hz | raw | LINK ID | 5 |
| TPWR | Uplink - transmitting power | mW | LINK ID | 6 |
| TRSS | Downlink - signal strength antenna (radio controller) | db | LINK ID | 7 |
| TQLY | Downlink - link quality (valid packets) | % | LINK ID | 8 |
| TSNR | Downlink - signal-to-noise ratio | db | LINK ID | 9 |
| GPS | GPS Coordinates | lat + lon | GPS_ID | 0 |
| GSpd | GPS ground speed | kmh | GPS_ID | 2 |
| Hdg | Magnetic orientation / heading | deg | GPS_ID | 3 |
| Alt | GPS Altitudes | m | GPS_ID | 4 |
| Sats | GPS Satellites acquired | raw | GPS_ID | 5 |
| RxBt | Battery voltage | V | BATTERY_ID | 0 |
| Curr | Current draw | A | BATTERY_ID | 1 |
| Capa | Current consumption | mAh | BATTERY_ID | 2 |
| Bat% | Battery remaining | % | BATTERY_ID | 3 |
| Ptch | FC pitch angle | radians | ATTITUDE_ID | 0 |
| Roll | FC roll angle | radians | ATTITUDE_ID | 1 |
| Yaw | FC yaw angle | radians | ATTITUDE_ID | 2 |
| FM | Flight mode | See below | FLIGHT_MODE_ID | 0 |
CRSF flightmode
| Flight Mode | Meaning |
|---|---|
| !FS | Failsafe mode |
| RTH | Return To Home mode |
| MANU | Passthru mode |
| ACRO | ACRO mode |
| STAB | Angle mode |
| HOR | Horizon mode |
| AIR | Air mode |
| WAIT | Wait for GPS lock |
| appended * | FC is not ARMED |
Smartport protocol
Here is the set of telemtry fields sent via Smartport can be seen here : https://github.com/betaflight/betaflight/blob/daa6df80248c9a806b7d77c402d415a15f4e2667/src/main/telemetry/smartport.c#L89
Other protocols
All telemetry protocols can be inspected here : https://github.com/betaflight/betaflight/tree/master/src/main/telemetry