I’ve been looking over the ELRS 4.0 release notes.
I’m not really qualified to say whether any of the changes affect ArduPilot - but I trust the DEV’s are taking a look.
The channel 5 arming thing is gone - or changed. But for some reason on my RadioMaster equipment I never saw that it came into effect - maybe it’s just a BetaFlight thing.
The release notes report improved telemetry. I use Yaapu - so that’s appreciated. I’m wondering if upgrading to the new RadioMaster TX16S Mark-3 with it’s faster processor will benefit.
I haven’t implemented ELRS Backpack - but maybe the improved telemetry is helpful there too.
Lastly, I’m curious how ELRS 4.0 might effect the mLRS protocol.
We looked into the arming changes. Channel 5 arming is not gone. There is an option to use a spare, otherwise unassigned transmitter switch as the arming flag instead of dedicating channel 5. You can continue to arm as usual with ch5 or you can use the new feature as desired. Using the new feature would require you to both arm the autopilot AND flip the switch on your transmitter to the arm position. It does potentially buy you an additional full resolution channel.
mLRS is a fork, so it should be wholly unaffected by mainline releases unless Olli chooses to incorporate new features.
I wasn’t anticipating any adverse impact. But advantageous impacts are always appreciated.
The channel 5 “arming” thing is a bit of a mystery to me. The release notes do say that the feature is still available - but can be assigned to other channels.
I had previously read that the ELRS LUA script could disable the “arming” feature - but I never found it on my RadioMaster Pocket or RadioMaster TX16S model 1.
In fact I haven’t found where the “arming” feature exists at all on my equipment. I’m sure there’s an explanation - I just haven’t come across it yet. Who knows - maybe I’ve been flying around in low power mode and just didn’t know it. I seem to recall reading that this feature wasn’t implemented on ELRS targets for all equipment - so maybe my transmitters just don’t support it.
One thing I’ve started doing is using a Widget page with ELRS telemetry values that show ELRS status values. These are things not captured by Yaapu or Ardupilot. It’s helpful to have visibility to these values.
I use both ArduPilot and PX4, and I started using this approach because of PX4 telemetry limitations. But it works on either system.
Arming ExpressLRS is required to get full dynamic or user-set power from the transmitter. It resides solely on the handheld, hence the reason you can now optionally just assign a switch rather than a switch + channel.
You need to upgrade to the latest EdgeTX to get full advantage of the non-channel 5 arming.
I’ve tried out ELRS 4.0 already. I had to update my radio and Yaapu scripts, but it all seemed to work really well. The telemetry downloads are fast enough to be practical and usable. It’s wonderful to have Yaapu back working on the main branch of the firmware. Key for me is that I wasn’t getting the close range fail-safes that I was getting when I tried ELRS/MavLink on 3.5. So far I’m happy with it and plan to try it on a few different set ups.
it is not a fork. mlrs is completely separate from elrs and was not forked from elrs. it is completey different development. this is incorrect information.
Only difference I noticed is that You can, optionally, set arming for RC14 instead of RC5 in ardupilot, as this channel reflects elrs armed state regardles of ch5/switch assignment in radio.
Second thought - not sure how this CH14 behaves in failsafe condition, need to check that for sure.
Also if I remember correctly in gemini mode, telemetry data rate is doubled, so if anyone using mavlink over elrs there should be some improvement there, but did not try it myself
