Skydemon with FLARM via Stratux

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Skydemon with FLARM via Stratux

Author	Message
efrenken	efrenken posted 7/22/2019 4:31:43 PM Post Details Share Post
Group: Forum Members Posts: 265, Visits: 3.5K	Tim, Why do you recommend GDL90 as the best protocol? Since I‘ve been using the protocol b3nn0 has described above I don‘t have any gaps within my logs and I get the ring around my position for non-ADS-B traffic. By using the GDL90 protocol I get a gap every 3 mins in my logs and no ring. Eric
	Reply Like 2
Tim Dawson	Tim Dawson posted 7/24/2019 3:32:42 PM Post Details Share Post
Group: Forum Members Posts: 7.8K, Visits: 8.5K	It's just generally a more robust protocol, and it can receive UAT weather and encrypted FLARM messages too. This may not be applicable for you, of course. What sort of device are you using SkyDemon on where you're seeing gaps in recording?
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b3nn0	b b3nn0 posted 7/24/2019 6:03:32 PM Post Details Share Post
b Group: Forum Members Posts: 41, Visits: 3.4K	Hi Tim, this happens to many users on iOS and Android with the Stratux. I have debugged it thoroughly on the Stratux side and am fairly convinced that it is some wonkyness in SDs GDL90 implementation. I had a lengthy discussion about it with your support (Hannah, iirc), but it did not look like SD is willing to change something. On the Stratux side, I implemented a workaround by sending the GDL90 hearbeat message much more often, if enabled in the settings, which seems to reduce the gaps quite a bit to 2-3 per hour, instead of 20-30 per hour.. Feel free to check my communication with Hannah from support for more detail of my analysis. In short, it seemed like the UDP connection has some lags from time to time, especially when the phone is under load. The RaspberryPi/Stratux network stack then seems to try to correct that by multiple retransmissions that are received in a short time on Android/iOS. That seems to confuse SD, indicating a short connection drop of 2-3 seconds and drawing a gap in the log later. During flight, it can only be noticed by the vertical radar screen shortly dropping out and then being regenerated. Note that errors like this are to be expected for UDP connections, at least it's written in the RFC that applications should be tolerant to that. I have cross-checked this with a different GDL90 client implementation, which just checks the checksums and dumps the information in real-time. This way, it was easy to see the gaps and retransmissions at a similar rate that SD drops out. Also, I used two devices running SD, both connected to the same Stratux, and both show these gaps, but at different times. So the packet content is certainly correct - it's just the transmission which SD assumes is interrupted. Note: Feel free to contact me directly if you need more info - I'm the maintainer of Stratux Europe Edition. Edited 7/24/2019 6:04:16 PM by b3nn0
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efrenken	efrenken posted 7/24/2019 10:55:04 PM Post Details Share Post
Group: Forum Members Posts: 265, Visits: 3.5K	Tim, I use SD (newest Beta release) on an iPad Pro with the recent iOS. I‘ve experienced exactly what b3nn0 has written in his post above. Eric
	Reply Like 3
Tim Dawson	Tim Dawson posted 7/25/2019 9:33:56 AM Post Details Share Post
Group: Forum Members Posts: 7.8K, Visits: 8.5K	I don't suppose either of you have a SkyEcho or SkyEcho 2 product around? Those are very popular, use GDL90 and we have never observed any problems with them. Then again, they are not built on top of a Raspberry PI, I don't know if that makes a different to the networking stack.
	Reply Like 2
Alf	Alf posted 7/25/2019 2:22:03 PM Post Details Share Post
Group: Forum Members Posts: 22, Visits: 20	Hi Tim, I use SkyEcho 2 (mainly) and Stratux for testing purposes with the same Android devices. I could observe the mentioned drop outs also with SkyEcho 2, but only on older devices. I use an older Samsung Note 4 in the Front Cockpit and a new Xiaomi Mi Max 3 in the rear Cockpit. The Xiaomi had no drop outs with SkyEcho 2 and SD, but the Samsung any few seconds, which was very annoying. When using Stratux, the drop outs were worse, and could even be observed on the new Xiaomi. This improved after the latest Stratux files from b3nn0. Hope that helps, Best regards, Alf Edited 7/25/2019 2:23:19 PM by Alf
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pilot-byom	p pilot-byom posted 7/25/2019 7:12:29 PM Post Details Share Post
p Group: Forum Members Posts: 323, Visits: 388	I use SkyEcho2 on a frequent basis and it also shows the drop outs with SD (running on iPad). Stratux is definitely worse, but in principle both shown the same issue with Skydemon (and btw i.e. ForeFlight does not suffer with the same setup).
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schoberh	s schoberh posted 10/2/2019 7:39:51 AM Post Details Share Post
s Group: Forum Members Posts: 3, Visits: 0	+x Alf - 7/22/2019 5:14:21 AM Hi b3nno, I had several flights last weekend with Stratux Europe Edition 1.5b2-eu008 BETA, 868 antenna for FLARM, SD as software. I am really impressed, it works fantastic! Thank you for all your work on this! BR, Alf Hi everybody! I purchased a Stratux box (currently image stratux-v1.5b2-eu010). Do I need to purchase this "FLARM Decoding Subscription" in order to get FLARM traffic displayed by Skydemon? https://www.skydemon.aero/store/flarmdecoding.aspx Thanks!
	Reply Like 2
techie59	t techie59 posted 4/28/2020 3:35:24 PM Post Details Share Post
t Group: Forum Members Posts: 16, Visits: 3	+x b3nn0 - 7/19/2019 3:47:58 PM This is most likely what your settings should look like for SD: (If you want to use the Flarm-NMEA protocol, the IP Address additionally needs to be 192.168.1.1, but that's optional. Get the rest working first). Disable AHRS if you don't have one in your Stratux. If you have an ADS-B out equipped airplane, enter your transponders HEX in the top right. To get the Flarm-NMEA option in SkyDemon, you, of course, need to enable that in the Settings "FLARM via Air Connect". But as I said, that's optional. Yes, I recommend using an 868Mhz antenna instead of the 978. Reception range will be better. First, thanks a lot for all this wonederful work. I have updated the ROM with this EU version. Do I need to update the IP Address even though I will use it with the GDL90 protocol in SKydemon? Even though it is in that mode, will it gather the FLARM information? Why changing the IP address makes a difference (for my understanding)? REgards, Etienne (who can't wait to fly again)
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TouchTheSky	T TouchTheSky posted 4/29/2020 7:47:07 PM Post Details Share Post
T Group: Forum Members Posts: 151, Visits: 4.1K	+x techie59 - 4/28/2020 3:35:24 PM +x b3nn0 - 7/19/2019 3:47:58 PM This is most likely what your settings should look like for SD: (If you want to use the Flarm-NMEA protocol, the IP Address additionally needs to be 192.168.1.1, but that's optional. Get the rest working first). Disable AHRS if you don't have one in your Stratux. If you have an ADS-B out equipped airplane, enter your transponders HEX in the top right. To get the Flarm-NMEA option in SkyDemon, you, of course, need to enable that in the Settings "FLARM via Air Connect". But as I said, that's optional. Yes, I recommend using an 868Mhz antenna instead of the 978. Reception range will be better. First, thanks a lot for all this wonederful work. I have updated the ROM with this EU version. Do I need to update the IP Address even though I will use it with the GDL90 protocol in SKydemon? Even though it is in that mode, will it gather the FLARM information? Why changing the IP address makes a difference (for my understanding)? REgards, Etienne (who can't wait to fly again) Etienne, It is my understanding that you don't need to change the default IP address (192.168.10.1) if you plan to continue using GDL90 with SkyDemon - it will continue displaying FLARM targets. Changing the IP to 192.168.1.1 simply indicates to SkyDemon that the FLARM NMEA protocol is used instead.
	Reply Like 3