Taranis RTC resets - battery OK

[CJB]

I can not keep the RTC to operate once I turn it off. Something, someone may know a simple fix (I'm hoping).
My radio is a Taranis X9D SE with 2.3.11 firmware.
It's over 2 years old and everything else works flawlessly. However, I'm tired of resetting clock and date at every start up, especially when I need time stamps for logs.

I do not get RTC low warning because:

Battery was replaced and the RTC voltage in HARDWARE reads - 3.5 volts. I've poured over the internet and solutions are all over the place. I honestly don't believe all answers work because they're too weird. The only suggestion not given was: Put on your ruby shoes and click your heels together while saying 'There's no place like home".

I hope this doesn't mean sending in the Tx.

John B

 

[Wayne]

We are always happy to take a look. but it is almost always that battery. Can't think of anything else. Make sure it is installed correctly.

 

[CJB]

Hi Wayne,

I am certain it is NOT the battery, I bought a batch of them (Lithium 3.3V CR1220) off Amazon and gave one to my flying buddy (his died) and it works fine. I just put one in my son's old Taranis and it works!

What do you need for me to do to send it?

John Bromley

 

[Wayne]

Just email us at contact@alofthobbies.com and let the team know about the issue, or just link to this thread. They will get you the details for sending the radio in for service.

Sorry for the trouble!

 

[darkside_floyd1]

John - Did you ever get your RTC to work? I'm experiencing the same issue.

 

[alm_nl]

When you replace the RTC battery, you have to set the time twice to have the radio remember it. Set the time, turn off the radio, turn it back on and set the time again, then turn it off and on again and it should show the correct date and time.

 

[OliviaNewman]

Hey @darkside_floyd1, usually if it's not the battery, it points to an issue with the RTC circuit on the mainboard. Did you ever send it in for service? It's often the most reliable fix for persistent RTC problems after a battery swap.

 

[darkside_floyd1]

Hey @darkside_floyd1, usually if it's not the battery, it points to an issue with the RTC circuit on the mainboard. Did you ever send it in for service? It's often the most reliable fix for persistent RTC problems after a battery swap.

No I never did send it in or even inquire as the cost is probably not worth it to me. I was messing around with this again today. Now that AI is more of a thing I was asking ChatGPT and Google AI... No luck. Actually very frustrated with ChatGPT and how poor it's logic and suggestions work. I've retested my battery and it's 3v. I've tested the voltage at the main STM chip with the main battery removed... following the trace from the RTC battery holder to the STM and at the STM I'm getting 3v. Some of the ChatGPT suggestions were around a faulty diode but getting power to the STM leads me to belive that is not the case. It also suggested intermittent issues due to solder joins including around the crystal. But I'm not having intermittent issues.

I was also looking at the source code for OpenTX and saw this in rtc.cpp
#define RTC_ADJUST_TRESHOLD 20 // how much clock must differ before adjustment is made [seconds]
/*
Changes RTC date/time to the given UTC date/time if:
* RTC_ADJUST_PERIOD seconds have elapsed from the last time this function adjusted the RTC clock
* AND if actual RTC clock differs from the given clock by more than RTC_ADJUST_TRESHOLD seconds
* Function does nothing for a minute around midnight, where date change could produce erroneous result
*/
I've tried making sure my time change to today's date hence big vs the 1970-01-01 00:00:00 default. I've waited >1m from power on to change. I've waited >1m after change to power cycle. I've tried the set it, power cycle, set it again trick. I've tried changing models after setting it to try to get it to write and save the date. all with no luck.

I don't really use the radio all that much anymore. But still bugs me that this never worked. I've considered buying a new main board but it's just not worth it to me.