How to log Rx data?

[Allan Bennett]

Following a disastrous crash on Sunday I realised that I could look at the log file to see if there's an obvious cause, other than pilot error.

Luckily I had enabled logging several months back, with interval set at 0.2 seconds as recommended in the thread I'd read. But when I opened the log file for my crashed model I saw only data relating to the Tx -- all the stick and switch positions, and Tx battery voltage -- but nothing about the Rx such as RSSI and Rx voltage.

For the model in question I was using an RX6R receiver and Taranis X9D + 2019 transmitter. I've enabled logging in the Special Functions screen as follows:- SG^ SD Logs 0.2, where SG is the throttle cut switch, but I'm wondering if I've even done that right, for my logs go far beyond the point where I flipped SG to enable the throttle.

Can someone help me with info about how to get more-useful data about the Rx into my logs please? All I can find online is how to create and view GPS logs, which I'm not interested in (at the moment!).

[MattyB]

Hi Allan. I don't think there is anything wrong with your switch setup, I just don't think you have RSSI set to log at the moment. I'm not an expert on doing it via global variables as I've never setup that way, but if you open your list of telemetry sensors, edit the RSSI sensor and check the box for logs all should be well:

This video (from which the screenshot above was grabbed) should help; it's for a voltage sensor but exactly the same method can be used for any sensor, including RSSI…

Edited By MattyB on 20/10/2020 16:14:06

[Philip Lewis 3]

Hi, all I have to enable logging is essentially the same, just in my case SF up, so if your safety switch is SG away from you it should work, I would check you have it the right way round though as that could explain why it kept going. Sensors need a tick in the telemetry page to log (by default they are ticked on discovery) but stick positions should log automatically.

[Peter Christy]

When setting up a model, I usually go to the telemetry page, "Delete all sensors" and then "scan for new sensors". This makes sure I have all the required sensors operating correctly.

--

Pete

[Allan Bennett]

Thanks for those very prompt replies. But, am I beig a bit thick here? I can't find any Sensors menu as you show in your screenshot Matt. I'm on v2 firmware, but I've also checked my v1 Taranis and can't find a Sensors menu there either, so I've got no tick box to enable logging. I have no external sensors, so would that be why I don't have the menu item? Surely RSSI and Rx voltage don't need an external sensor to monitor them?

Philip, I've been to the Telemetry screen but there's no tick box to enable, or anything like that. There's 'Add a new sensor', etc. and, under the RSSI heading, a tick box to 'Disable telemetry alarms', which is not checked.

SG away from me enables the throttle -- oh bother, it's not SG, it's SD, so that explains why I had continuous logging!! SG is the spring-loaded switch which is always away from me by default.

[MattyB]

Posted by Allan Bennett on 20/10/2020 16:27:19:

Thanks for those very prompt replies. But, am I beig a bit thick here? I can't find any Sensors menu as you show in your screenshot Matt. I'm on v2 firmware, but I've also checked my v1 Taranis and can't find a Sensors menu there either, so I've got no tick box to enable logging. I have no external sensors, so would that be why I don't have the menu item? Surely RSSI and Rx voltage don't need an external sensor to monitor them?

Philip, I've been to the Telemetry screen but there's no tick box to enable, or anything like that. There's 'Add a new sensor', etc. and, under the RSSI heading, a tick box to 'Disable telemetry alarms', which is not checked.

Allan, don't be confused between RF (XJT module) and OpenTX firmware. How the sensors are detected and handled is a function of OpenTX; it's nothing to do with the RF version. Providing both your TXs are on a recent version (anything after OTX 2.1) they will work exactly the same wrt telemetry setup. Certainly the new TX which you used on Sunday will definitely have the telemetry sensors setup as per that video.

Here's what to do:

• Switch on TX
• On home screen press Menu once - you should see the list of models available
• Long press Page twice to get to the Telemetry screen
• Scroll down - the list of sensors should be just off the bottom of the screen
• Press Enter on the sensor RSSI
• Scroll down until you see the Logs checkbox, then check it

PS - The RSSI and RxBt sensors are just two other sensors as far as the TX is concerned; they are no different from other sensors that aren't built into the Rx.

[Allan Bennett]

Yes, I'm on OTX 2.3.9 and I've got the Telemetry screen.

Its first line is 'RSSI' followed by 'Source (default)' then 'Low alarm 45' then 'Critical alarm 42' then 'Disable telemetry alarms' with a tick-box, which is currently unticked.

Next comes 'Sensors' with 'Discover new sensors', 'Add a new sensor', 'Delete all sensors', and 'Ignore instances' with a tick-box which is currently unticked.

Lastly there's 'Variometer' with 'Scource', 'Range -10 10', 'Center -0.5 0.5 Tone'

And that's it: No 'Logs' checkbox.

BTW, if Philip is still there, I was having a senior moment! My throttle kill switch is SG on all models, so that doesn't explain my continuous logging.

[MattyB]

Posted by Allan Bennett on 20/10/2020 17:15:26:

Yes, I'm on OTX 2.3.9 and I've got the Telemetry screen.

Its first line is 'RSSI' followed by 'Source (default)' then 'Low alarm 45' then 'Critical alarm 42' then 'Disable telemetry alarms' with a tick-box, which is currently unticked.

Next comes 'Sensors' with 'Discover new sensors', 'Add a new sensor', 'Delete all sensors', and 'Ignore instances' with a tick-box which is currently unticked.

Lastly there's 'Variometer' with 'Scource', 'Range -10 10', 'Center -0.5 0.5 Tone'

And that's it: No 'Logs' checkbox.

Try another sensor discovery (scroll to the bottom of that screen to do this). I have all the RSSI stuff you list at the top of the telemetry screen:

...but I also have RSSI listed under the list of Sensors further down, just above "Discover new sensors":

It's that second entry that you need to press enter on and edit; that is where the log checkbox will be (at the very bottom of the next screen).

Edited By MattyB on 20/10/2020 17:35:51

[Philip Lewis 3]

Posted by Allan Bennett on 20/10/2020 17:15:26:

BTW, if Philip is still there, I was having a senior moment! My throttle kill switch is SG on all models, so that doesn't explain my continuous logging.

I think you have two issues here and I would doubt that they are related.

Regarding the logging of data, as far as I am aware logging will only take place once it is enabled, if it isn't enabled it won't log anything at all.

If I were you I would double check that switch position, the only possible other scenario I can think of that would enable logging to continue would be if you had another switch also enabling logging which would still be "on", worth checking all your other special functions.

I think on the other issue you probably just need to click on discover sensors, you can see any active ones listed as they will have an * beside them.

Don't forget to then click on stop discovering sensors.

Edited By Philip Lewis 3 on 20/10/2020 18:28:34

[Allan Bennett]

Posted by MattyB on 20/10/2020 17:19:30:

Posted by Allan Bennett on 20/10/2020 17:15:26:

Yes, I'm on OTX 2.3.9 and I've got the Telemetry screen.

Its first line is 'RSSI' followed by 'Source (default)' then 'Low alarm 45' then 'Critical alarm 42' then 'Disable telemetry alarms' with a tick-box, which is currently unticked.

Next comes 'Sensors' with 'Discover new sensors', 'Add a new sensor', 'Delete all sensors', and 'Ignore instances' with a tick-box which is currently unticked.

Lastly there's 'Variometer' with 'Scource', 'Range -10 10', 'Center -0.5 0.5 Tone'

And that's it: No 'Logs' checkbox.

.......but I also have RSSI listed under the list of Sensors further down, just above "Discover new sensors":

It's that second entry that you need to press enter on and edit; that is where the log checkbox will be (at the very bottom of the next screen).

Edited By MattyB on 20/10/2020 17:35:51

I don't have any of those five entries. Presumably your first three are from an external sensor, but RSSI and RxBt should come direct from the receiver? Sounds like I've got to 'Discover sensors' again, as suggested by Philip.

Out of interest, I've got one model with two temperature sensors on it, and they show in its listing, but still no RSSI and RxBt. Perhaps I didn't realise the significance of those two when I added the temperature sensors several years ago.

A job for tomorrow. Thanks guys.

[MattyB]

Posted by Allan Bennett on 20/10/2020 20:06:55:

I don't have any of those five entries. Presumably your first three are from an external sensor, but RSSI and RxBt should come direct from the receiver? Sounds like I've got to 'Discover sensors' again, as suggested by Philip.

Actually all of those are from a G-RX8 receiver which has an integrated vario. Before I clicked on “Discover new sensors” on OTX 2.3 I was getting nothing back from it, even though the top section of the telemetry page still had those std things about RSSI alarms etc. I’m confident that if you power up the RX and do a sensor discovery you’ll get what you need to log RSSI.

Edited By MattyB on 20/10/2020 20:35:13

[Allan Bennett]

I'm getting somewhere, but not all the way!

I've been into the Telemetry screen and Discovered new sensors, stopped discovery, then deleted the ones I didn't want, so I'm left with RSSI and RxBt.

I've then clicked on each of the two sensors in turn, and checked that the 'Logs' tick-box is checked (it was), but after a dummy run with the model with SG turned 'on' and 'off', then viewing the log file in OTX Companion, RSSI and RxBt are still not listed as available fields.

I also tried with another model which already has a couple of temperature sensors, which have been working well for a few years sending alerts to my Tx, but still when I view its log file I see neither the temperature sensors nor RSSI and RxBt.

So, any ideas please what step it is that I'm still missing?

[Philip Lewis 3]

The only thing I can think of is rediscover sensors then stop but this time don't delete any, I know it shouldn't make a difference but indulge me anyway.

Regarding the log files that you do have though, do they now start and stop when the switch is flipped? You should be able to tell from the time in Companion if you note what time you flip it on and off.

I have one last idea but I'll let you try that first.

[MattyB]

Posted by Philip Lewis 3 on 21/10/2020 16:17:54:

The only thing I can think of is rediscover sensors then stop but this time don't delete any, I know it shouldn't make a difference but indulge me anyway.

Regarding the log files that you do have though, do they now start and stop when the switch is flipped? You should be able to tell from the time in Companion if you note what time you flip it on and off.

I have one last idea but I'll let you try that first.

Agreed, all good advice. I would never delete any sensors detected; there is no need to do so, the logs take up a tiny space so it doesn't really achieve anything and might lead to an unexpected issue.

[Allan Bennett]

OK, I've gone back to one of my models and Discovered sensors then Stopped discovery, and still no joy. In fact, it doesn't seem to be logging the sensors at all, for when I use OTX Companion to view the log I get an error message that 'The selected log file contains 2198 invalid lines out of 2271 total line' and, according to the date/time stamps, the logging I've done just now doesn't exist.

[Allan Bennett]

CRACKED IT !!

For my next trick I deleted all the log files for the particular model I was using for testing, then when I ran another test all the fields were displayed when I viewed the file.  As you suggest, I won't bother deleting any sensors either after I've detected them.

So I'm going to delete all my other log files from the SD card, for they're obviously the root of the problem. Could it be becuase they were created with an previous version of OTX?

Edited By Allan Bennett on 21/10/2020 16:42:39

[Philip Lewis 3]

The error is (I think) because you have sensors that have been deleted and then rediscovered on the same day. Delete at least todays log file before going any further as it will simply try and add to an already corrupt file.

Then see if you are actually receiving any telemetry in the first place, you can easily check this by trying to turn the TX off first and you should get a warning that a RX is still connected, you should also get a "telemetry lost" message when you power down the RX with the TX still connected.

If that is the case then rebind the receiver and make sure it is rebound with telemetry on, hot money this end is that is your problem.

[Philip Lewis 3]

Presumably they aren't any use so yes you might as well delete them but they shouldn't be causing any problem it was just today's one.

Logging turning on and off when it should now?

Edited By Philip Lewis 3 on 21/10/2020 16:48:43

[Allan Bennett]

I think I know my way around it now: Logging is turning on and off with SG, and I've also discovered that deleting sensors is not good, for it seems to corrupt the log file and all the subsequent entries for the same model.

So to summarise what I've done which seems to be working:-

I've set a global function to activate logging at 0.2 second intervals with SG^, thus logging all the time my motor is running. If I were a glider guider I guess I'd have a dedicated switch for it, rather than my throttle-cut switch.

I've discovered sensors for each model, and NOT deleted any unwanted ones.

I've deleted all my historic LOG files -- they're no use whatever, for none of them contain any RSSI or RxBt data.

Thanks each for your patience and assistance.

[Philip Lewis 3]

All sounds good to me.

Phil

[MattyB]

Case closed you honour!

[Allan Bennett]

Now at least I should be able to prove my next crash isn't my fault

[Allan Bennett]

Another question, please: I've just looked at the log from yesterday's flights, and it recorded correctly. It was a small quad flying ovals around a rugby field, and RSSI fluctuates rapidly and greatly, presumably as I flew to and away from myself. The data shows RSSI ranging from 106 to 49 -- is that the kind of numbers you would expect for flights less than 50m away from me? The receiver is an RXSR incorportated into FrSky's Omnibus F4 V6 flight controller, and the transmitter is Taranis 9D+2019 with v2 firmware.

[MattyB]

Short answer - it depends, in the main on how your aerials are oriented. If it's an all carbon frame you are going to expect to see some masking in certain orientations and quads are generally flown pretty low, so I am not really surprised by those numbers; they are what I would expect for a ground  range test for a glider with extensive carbon too.

Edited By MattyB on 26/10/2020 14:53:59