CRSF Distinct GPS Altitude from Barometric Altiude

[JimB40]

Is there an existing issue for this feature request?

• I have searched the existing issues

Is your feature request related to a problem?

Seems that for now EdgeTX uses for both values the same sensor name "Alt"

1. If FC is equiped with barometer and GPS is connected - "Alt" Sensor wil hold barometric altitude value
2. Same case if GPS is connected - "Alt" Sensor will hold GPS altitude value (barometric altitude is not available anymore)

Those are different values so would be good to retain both.

Describe the solution you'd like

1. Barometric altitude uses STR_SENSOR_ALT "Alt"
2. GPS altitude uses STR_SENSOR_GPSALT "GAlt"

Describe alternatives you've considered

No response

Additional context

No response

[3djc]

Name don't have to be unique for telemetry sensors. In your example, are both actually sent by FC ? Because if they are, you should already get both today.

Here you can see that we treat GPS Alt and Baro Alt distinctively:

edgetx/radio/src/telemetry/crossfire.h

Line 65 in 79bde7e

enum CrossfireSensorIndexes {

[JimB40]

AFAIU

GPS 0x02 frame

1. FC (ie Betaflight) encodes GPS data and sends CRSF frame
   https://github.com/betaflight/betaflight/blob/b277364b2cd79d7d7d7192c8a48603fe38638f67/src/main/telemetry/crsf.c#L259

2. EdgeTX gets this CRSF frame and decodes values
   

   edgetx/radio/src/telemetry/crossfire.cpp

   Line 150 in 79bde7e

   processCrossfireTelemetryValue(GPS_ALTITUDE_INDEX, value - 1000);

3. EdgeTX creates sensor using as name STR_SENSOR_ALT "Alt"
   

   edgetx/radio/src/telemetry/crossfire.cpp

   Line 58 in 79bde7e

   CS(GPS_ID, 4, STR_SENSOR_ALT, UNIT_METERS, 0),

same happens for Barometric Altitude & Vertical Speed 0x09 frame

1. BF Encoding
   https://github.com/betaflight/betaflight/blob/b277364b2cd79d7d7d7192c8a48603fe38638f67/src/main/telemetry/crsf.c#L347

2. EdgeTX Decoding
   

   edgetx/radio/src/telemetry/crossfire.cpp

   Line 155 in 79bde7e

   case BARO_ALT_ID:

3. EdgeTX creates sensor using as name STR_SENSOR_ALT "Alt" (the same)
   

   edgetx/radio/src/telemetry/crossfire.cpp

   Line 65 in 79bde7e

   CS(BARO_ALT_ID, 0, STR_SENSOR_ALT, UNIT_METERS, 2),

What do you mean?
I should have two sensors named "Alt"?

[3djc]

Exactly, which is why I'm wondering if there is a mechanism in BF that says don't send alt twice or similar

[JimB40]

0x09 frame has also Vertical Speed information. VERTICAL_SPEED_INDEX

edgetx/radio/src/telemetry/crossfire.cpp

Line 172 in 79bde7e

processCrossfireTelemetryValue(VERTICAL_SPEED_INDEX, value);

But VSpd never shows.
It might be on BF side that 0x09 is not send

Can we log somehow recieved CRSF frames types?

[3djc]

You can mirror the telemetry stream on a serial port