OpenTX channel assignment in firmware

[Dale Bradly]

Gents, some assistance to help me figure this out please.

Existing plane, all setup and flown, zero changes made to plane lately.

Radiomaster TX16S. Again, zero changes to model setup, RX or any part thereof.

What i have changed since the last time I flew this setup, was update the firmware on the radio (in order to have a play with Companion.)

 

Some playing around has suggested a bunch of channels have changed around, I do recall a question around what your preferred default channel assignment is, and one of the upgrade files being this, i am sure i used the correct one, but it appears not. 

All the options, mixes, outputs etc i can see within the radio reflect my preferred setup (TAER - recall they were before the update) but thus isn't what is actually being transmitted, as there must be a glitch in the matrix re the channel assignment in firmware.

 

So can can someone provide a simple guide as to which file(s) need to be reflashed to achieve this please? Note i would prefer not to upgrade everything for the sake of it.

 

 

 

[Peter Christy]

Where to start? Firstly, I don't have a RadioMaster, my OpenTx transmitters are both FrSky, so my mileage may vary from yours. It shouldn't, but it might!

 

Like you, I use a default of TAER, as I was coming from a JR background. However, OpenTx default is AETR (from memory). If you do not specify this at the time of download (via Companion), you will get AETR. The easiest way to prevent this happening accidentally is to specify your preferred channel order in your radio profile setting in Companion.

 

Open Companion, and see if you have a profile setup up  (Settings/Radio Profile from the top level tab, or click on the gearwheel icon, and select the radio profile tab). Towards the bottom of the page, you will find the mode selection drop-down, and under that will be the default channel order you have selected. It sounds as if yours is NOT set to TAER.

 

There are three possible solutions. One is to re-download OpenTx via Companion, having made sure you have set the profile correctly to your requirements. If the only thing you change is the channel order, you shouldn't need to edit anything else once you have re-installed.

 

The second way is to simply re-order the channels in your existing set up. There are plenty of guides on how to do this, but if you have a lot of models, this could be a pain! Also, depending on whether you re-order at the input page, mixers or output page could affect any mixes, etc, that you have set up. It would also mean editing every model again if you upgrade OpenTx in the future with your desired channel order.

 

Probably the simplest solution in the short term is to simply re-order the default on your Tx. I haven't tried this, but it should work! A long press on the "menu" button (or whatever RadioMaster uses) should get you into the Radio SetUp menu (rather than the model setup you get from a short press). Page across to the "Radio SetUp" page (3rd page on my X9D, where you set the date and time, etc). Scroll to the bottom of the page, where the penultimate line should be "Default Channel Order". Select TAER.

 

This should change the order for all models.

 

As I say, I haven't tried this, and I'm not using RadioMaster, so after you've done this, check everything VERY carefully!

 

Best of luck!

 

--

Pete

 

[Peter Christy]

PS: Re-reading your post, I realise that you can also change the channel order in the multi-protocol module when you download the firmware for that! That has nothing to do with OpenTx, but it is VITAL that the two channel orders match! Whatever channel order you choose to use in OpenTx, you must download the multi-protocol firmware with the same channel order.

 

--

Pete

 

[Mike Blandford]

The multi-protocol module can "map" your radio channels to other channels for transmission. This is done so you may use a "standard" channel order for your models, but then match specific requirements for different protocols. DSM, for example, does use TAER I believe. If you use something different (say AETR), then the MPM may be set to change the channel mapping when DSM is selected as the protocol.

There is also a control bit that may be set in the data sent to the MPM that enables/disables this channel mapping. I don't know how openTx controls this bit. This function may well have been added since the version you had and the update, and be defaulting to allowing channel mapping (it is a "disable" mapping function so a default of 0 would allow mapping).

 

Mike

[Peter Christy]

That's handy to know, Mike! I was unaware of the "disable" bit - and no, I don't know if or how OpenTx implements it either! ?

 

I have an IRX4+ - the one with the rotary switch, since I sometimes use it with my old PCM-9. For that reason I always download (or compile) it for TAER. When I wrote my initial reply above, I'd forgotten that RadioMaster had a built-in MPM, hence my PS. When I re-read the original post, I wasn't absolutely sure whether the OP was referring to actual OpenTx or the MPM firmware. Of course if the two don't match (and channel mapping is not disabled in the MPM), you can end up with a very confusing situation!

 

One of many "gotchas" waiting for the unwary...! ?

 

--

Pete

 

[Dale Bradly]

Thanks for the suggestions. Haven't succeeded yet though.

Peter, your suggestions re the default channel setup in Companion is TAER. Likewise, the reorder the default order in OpenTX is already on TAER. Since these wasn't the answer, it must be the MPM firmware. Downloaded the latest TAER version, updated this, and zero change.

So further investigation and playing tomorrow. Worst case is i'll have to adjust 4 or 5 model setups.

I note that this does nothing but reinforce my belief that technology is a pain in the backside and not ready for us mortals...

 

 

[Peter Christy]

OK, this is puzzling, and we must be missing something somewhere! Have you previously updated either OpenTx or the MPM firmware? I ask because I don't know what RadioMaster supply as a default channel order from new.

 

I've found this page, which makes some very salient points: https://www.multi-module.org/using-the-module/channel-order

 

Apparently, changing the default channel order in OpenTx will only affect NEW models. Existing ones will still have to be edited manually. (I've never had to do this, since I adopted TAER right at the outset.) The perceived wisdom seems to be that changing the existing order is best done at the mixer stage, and I have helped a fellow club member do this when he was setting up a very complex model. Its not as complex as it sounds! There is a very good video here (look about 4'20" in): https://youtu.be/z-OYFXUvcqw?t=260

 

I strongly recommend backing up all your models and settings to Companion before editing existing models. That way, if you get yourself totally confused, you can restore and start again! ?

 

As an aside, the page referenced above also tells you where to disable the channel-reorder setting for the MPM. This is done on a model-by-model basis, not system-wide. Channel order is particularly important on DSM systems, where some only have failsafe on Ch 1 (throttle).

 

Hopefully, some of this will get you sorted!

 

--

Pete