107 lines
4.0 KiB
Markdown
107 lines
4.0 KiB
Markdown
# Telemetry
|
|
|
|
Telemetry allows you to know what is happening on your aircraft while you are flying it. Among other things you can receive battery voltages and GPS positions on your transmitter.
|
|
|
|
Telemetry can be either always on, or enabled when armed. If a serial port for telemetry is shared with other functionality then then telemetry will only be enabled when armed on that port.
|
|
|
|
Telemetry is enabled using the 'TELEMETRY` feature.
|
|
|
|
```
|
|
feature TELEMETRY
|
|
```
|
|
|
|
Multiple telemetry providers are currently supported, FrSky, Graupner HoTT V4, SmartPort (S.Port) and MultiWii Serial Protocol (MSP)
|
|
|
|
All telemetry systems use serial ports, configure serial ports to use the telemetry system required.
|
|
|
|
## FrSky telemetry
|
|
|
|
FrSky telemetry is transmit only and just requires a single connection from the TX pin of a serial port to the RX pin on an FrSky telemetry receiver.
|
|
|
|
FrSky telemetry signals are inverted. To connect a cleanflight capable board to an FrSKy receiver you have some options.
|
|
|
|
1. A hardware inverter - Built in to some flight controllers.
|
|
2. Use software serial and enable frsky_inversion.
|
|
3. Use a flight controller that has software configurable hardware inversion (e.g. STM32F30x).
|
|
|
|
For 1, just connect your inverter to a usart or software serial port.
|
|
|
|
For 2 and 3 use the CLI command as follows:
|
|
|
|
```
|
|
set telemetry_inversion = 1
|
|
```
|
|
|
|
### Precision setting for VFAS
|
|
|
|
Cleanflight can send VFAS (FrSky Ampere Sensor Voltage) in two ways:
|
|
|
|
```
|
|
set frsky_vfas_precision = 0
|
|
```
|
|
This is default setting which supports VFAS resolution of 0.2 volts and is supported on all FrSky hardware.
|
|
|
|
```
|
|
set frsky_vfas_precision = 1
|
|
```
|
|
This is new setting which supports VFAS resolution of 0.1 volts and is only supported by OpenTX radios (this method uses custom ID 0x39).
|
|
|
|
|
|
### Notes
|
|
|
|
RPM shows throttle output when armed.
|
|
RPM shows when disarmed.
|
|
TEMP2 shows Satellite Signal Quality when GPS is enabled.
|
|
|
|
RPM requires that the 'blades' setting is set to 12 on your receiver/display - tested with Taranis/OpenTX.
|
|
|
|
## HoTT telemetry
|
|
|
|
Only Electric Air Modules and GPS Modules are emulated.
|
|
|
|
Use the latest Graupner firmware for your transmitter and receiver.
|
|
|
|
Older HoTT transmitters required the EAM and GPS modules to be enabled in the telemetry menu of the transmitter. (e.g. on MX-20)
|
|
|
|
Serial ports use two wires but HoTT uses a single wire so some electronics are required so that the signals don't get mixed up. The TX and RX pins of
|
|
a serial port should be connected using a diode and a single wire to the `T` port on a HoTT receiver.
|
|
|
|
Connect as follows:
|
|
|
|
* HoTT TX/RX `T` -> Serial RX (connect directly)
|
|
* HoTT TX/RX `T` -> Diode `-( |)-` > Serial TX (connect via diode)
|
|
|
|
The diode should be arranged to allow the data signals to flow the right way
|
|
|
|
```
|
|
-( |)- == Diode, | indicates cathode marker.
|
|
```
|
|
|
|
1N4148 diodes have been tested and work with the GR-24.
|
|
|
|
As noticed by Skrebber the GR-12 (and probably GR-16/24, too) are based on a PIC 24FJ64GA-002, which has 5V tolerant digital pins.
|
|
|
|
Note: The SoftSerial ports may not be 5V tolerant on your board. Verify if you require a 5v/3.3v level shifters.
|
|
|
|
## MultiWii Serial Protocol (MSP)
|
|
|
|
MSP Telemetry simply transmits MSP packets in sequence to any MSP device attached to the telemetry port. It rotates though a fixes sequence of command responses.
|
|
|
|
It is transmit only, it can work at any supported baud rate.
|
|
|
|
## SmartPort (S.Port)
|
|
|
|
Smartport is a telemetry system used by newer FrSky transmitters and receivers such as the Taranis/XJR and X8R, X6R and X4R(SB).
|
|
|
|
More information about the implementation can be found here: https://github.com/frank26080115/cleanflight/wiki/Using-Smart-Port
|
|
|
|
In time this documentation will be updated with further details.
|
|
|
|
Smartport devices can be connected directly to STM32F3 boards such as the SPRacingF3 and Sparky, with a single straight through cable without the need for any hardware modifications on the FC or the receiver.
|
|
|
|
For Smartport on F3 based boards, enable the telemetry inversion setting.
|
|
|
|
```
|
|
set telemetry_inversion = 1
|
|
```
|