"Adjust RTC" is turned on, but transmitter date/time doesn't get set?

[DurvalMenezes]

Per subject. I really need this to work since my Jumper T14 RTC is busted, and date/time goes back to 2000-01-01 00:00:00 every time I switch batteries. Setting it manually is a chore, and almost impossible to get the same-second accuracy I need to compare telemetry logs with what I see on the video OSD in my goggles' recordings.

I "used the source, Luke" and found this, which seems to indicate EdgeTX should be setting the transmitter RTC with the GPS date/time received over telemetry from the drone's GPS module, but for some reason it's not working: the drone has a full GPS lock on 15+ satellites, date/time on the OSD shows perfectly, but the transmitter date/time is never set.

In case it matters:

• Transmitter firmware: edgetx-t14 v2.11.33
• Drone: Flywoo Explorer LR4 with F722 Pro Mini V2 Flight Controller, running the factory firmware: Betaflight 4.5.1 w/ build key f760d9581f6d8bf1b083ef7d95c6384c (build options: USE_SERIALRX_CRSF, USE_SERIALRX_SBUS, USE_DSHOT, USE_PWM_OUTPUT, USE_ACRO_TRAINER, USE_GPS, USE_LED_STRIP, USE_MAG, USE_OSD_SD, USE_OSD_HD, USE_PINIO, USE_VTX)

EDIT: more info on the drone's peripherals that might or might not be involved in this:

• ELRS Receiver: Flywoo EL24E: https://flywoo.net/products/0-4g-flywoo-2-4g-expresslrs-elrs-el24e-el24p
• GPS module: Flywoo Goku Mini V3 (the plain, without compass version): https://flywoo.net/products/goku-gm10-mini-v3-gps

Thanks in advance for any hints on how to fix this.

[raphaelcoeffic]

The option is not very clear on this: it's the transmitter's GPS that is used, since time is not transmitted. I do agree it's unfortunate though the option is available despite your transmitter not having an internal GPS.

[DurvalMenezes]

Thanks for your response. In fact I considered that hypothesis (that the option only applied to a GPS directly connected to the transmitter), but the line in the EdgeTX source code I pointed to:

edgetx/radio/src/telemetry/telemetry_sensors.cpp

Line 135 in 16c7dbc

else if (unit == UNIT_DATETIME) {

is part of a function clearly named as processing telemetry items, ie data sent from the drone, and not from a directly attached GPS:

edgetx/radio/src/telemetry/telemetry_sensors.cpp

Line 87 in 16c7dbc

void TelemetryItem::setValue(const TelemetrySensor &sensor, int32_t val,

. In fact, it even checks the exact variable where the setting for the "Adjust RTC" option is stored before setting the transmitter RTC:

edgetx/radio/src/telemetry/telemetry_sensors.cpp

Lines 147 to 149 in 16c7dbc

	if (g_eeGeneral.adjustRTC) {
	rtcAdjust(datetime.year, datetime.month, datetime.day, datetime.hour, datetime.min, datetime.sec);
	}

Is this something that never got implemented, or am I completely misunderstanding the EdgeTX source code?

[raphaelcoeffic]

@DurvalMenezes Thx, I keep on learning something about that code. Even after years of maintaining it :-D Frankly, I don't know. But I've never witnessed it working like that for me.

[DurvalMenezes]

Thx, I keep on learning something about that code. Even after years of maintaining it :-D

May the gods-on-high (IAAE) grant us that we never stop learning :-) and seriously, thanks for your service in maintaining the code.

[3djc]

Only frsky and graupner gps send date times frames as far as I know. Do you have a date/time sensor after discovery?

[DurvalMenezes]

Do you have a date/time sensor after discovery?

Nope. The only GPS-related sensors my transmitter shows are "GPS" (which shows the coordinates), "GPSd" (which seems to be the distance), "Hdg" (heading) , "Alt" (altitude), and "Sats" (number of satellites).

[DurvalMenezes]

Only frsky and graupner gps send date times frames as far as I know.

Apparently it's on the CRSF specification: https://github.com/tbs-fpv/tbs-crsf-spec/blob/main/crsf.md#0x03-gps-time

[OzDruiD]

Apparently it's on the CRSF specification: https://github.com/tbs-fpv/tbs-crsf-spec/blob/main/crsf.md#0x03-gps-time
It's part of the CSFR spec, so ELRS RX should send it: [From discord - for discussion flow sake]

Why ? its quite possible, without looking at the code, that not all targets for all RXs and or protocols can\are coded to send back GPS time data via Telemetry. It might be in the TBS Crossfire specification but not pushed out for every single target by default. eg as 3djc maybe only Frksy and HotT are sending it out.

I think you probabily have found a niche case and as mentioned might need a build option or compile the target yourself -GPS_TELM or some flag, but will spend some time looking throught the various code srcs and targets.

Is it a Flywoo RX on it? What kind of GPS if not stock\default inbult one?
Inbuilt GPS - ccould be a Flywoo GOKU MINI GM10 V3 ??
Inbuilt RX - Flywoo EL24E TCXO 2.4GHz RX / Flywoo EL24P TCXO 2.4GHz RX ??

[DurvalMenezes]

Why ? its quite possible, without looking at the code, that not all targets for all RXs and or protocols can\are coded to send back GPS time data via Telemetry. It might be in the TBS Crossfire specification but not pushed out for every single target by default. eg as 3djc maybe only Frksy and HotT are sending it out.

Agreed, there are lots of perhaps/maybes. What I'm trying to do is to understand exactly where the issue is and then try to fix it.

think you probabily have found a niche case

IMO it's quite weird that it's such a "niche". My use case for it is to be able to match what's happening in the goggle recordings of my flights (where the GPS date/time are showing) with the telemetry logs recorded by my transmitter, and it never matches because the latter uses the RTC time which is hard to enter exactly (to the second) manually.

might need a build option or compile the target yourself -GPS_TELM or some flag

Agreed, that's what I'm looking for. But first I need to know who is "dropping the ball", ie whether it's EdgeTX on the transmitter, the ELRS receiver not passing it on, or Betaflight on the FC never sending it out in the first place.

Is it a Flywoo RX on it? What kind of GPS if not stock\default inbult one?

The RX is the Flywoo EL24E: https://flywoo.net/products/0-4g-flywoo-2-4g-expresslrs-elrs-el24e-el24p
And the GPS module is the Flywoo Goku Mini V3 (the plain, without compass version): https://flywoo.net/products/goku-gm10-mini-v3-gps

Thanks for bringing these up, at first I didn't think they were relevant. I will update the OP to include this info.

[DurvalMenezes]

Thanks in advance for any hints on how to fix this.

Also discussing this on the ELRS Discord server: https://discord.com/channels/596350022191415318/798006228450017290/1495019318516121743

[3djc]

#7317