UDP Packet Fail in 1.3.69

i think would need a wireshark capture to get a full picture on what is going on.

MP does support partial udp mavlink packets, but if out of order then it will fail with crc errors

@Michael_Oborne i am pmā€™ing you my wireshark capture right now.

please check the latest beta version

@Michael_Oborne solid work! Thanks so much!

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The folks at doodle labs wanted me to tell you they appreciate you knocking this out as well!

yeah, if the udp packets are aligned, there was never an issue, its just that the non mavlink aware radios can send like 5 bytes of part of a packet, and MP was screwing up the buffering

and thanks for the wireshark log, it did help

@Michael_Oborne Hi Michael. Aaron from Doodle Labs. Thanks for your work on patching Mission Planner. A number of Doodle Labsā€™ customers have reported that the fix in your latest Beta update solved the MAVLink packet drop issue when used with our radios. Will it be available in your next main release?

yes, it will be in the next main release. there is no plan at the moment for the release, but knowing this i can move it forward a little. but need to tidy up a few pending items first.

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Hey @Michael_Oborne, Iā€™ve been running into a similar issue with significant packet loss over UDP. Iā€™m running a similar setup to Evan with a doodle being fed serial and using ser2net to get UDP down. MP is on 1.3.79. Iā€™ll pm you a wireshark capture. I can see that there are some partial packets but Iā€™m not sure how to verify that your MP fix should handle it or if I need to adjust the ser2net setup or other radio settings.

looking at your log something else is going on

i see multiple destinations in the log, and i think its being round robin sent to those destinations

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ie there a multiple destination ports. which is not normal

So some confusion but good news on this. I donā€™t think I changed anything and for the first time with these doodles that have been on a couple of platforms it seems that FTP is working for the param grab and it now takes under 10s. I got the common.xml message wireshark plugin working to see the packets.

There are still a number of UDP packets that the parser plugin doesnā€™t recognize but everything seems to be working better. Also, the two destination port issue is gone. I may have had MP and mavproxy open. I can send the wireshark capture but I assume the unknown messages are a combination of partial packets which you said MP should be able to handle and messages not in common.xml.

Since Iā€™m not sure what ā€œfixedā€ it, if (when) the behavior happens again and I can pin down a cause I may be back.

Hi @Michael_Oborne ,
I am also facing similar issue, I see multiple CRC errors in Mission Planner, Link quality fluctuates between 30-60ā„…. Can you let us know what was the fixā€¦
the max pkt size my telemetry radio can take in 250 bytes.
Right now I am running SITL at one end and sending the data via the Telem-Radios and on another end 2nd Radio is connected to Mission Planner(version 1.3.80).


I debugged furtherā€¦I had a doubt that my transmited pkt and received pkt has error.
So I basically wrote a simple python code and tested if my transmitted pkt is same as received pkt.
I sent random 250 byte data via uart-1 interface and read back data on uart2 interface and did a compare.
I see there ā€¦ transmitted pkt and receive via lora are same. So no issues hereā€¦
Ran tests with multiple PKT size starting from 64 byte to all the way 250bytes.
Tested with 10,000 pkts alsoā€¦ Results came similarā€¦
7 error and 9993 ok.
So I have ruled out the issue of telemetry module having issue.

However
When my pkt size exceeds 250 bytes Letā€™s say (254 bytes)[ Telemetry firmware I am running can handle max 250 bytes]
I see the last 4 bytes chopped off and coming as the 1st 4 bytes of the next received pkt.

My telemetry module is Mavlink un-awareā€¦ I am posting this as similar issue with Doodle Labs was addressed hereā€¦
I tried with different versions of Mission Planner ; latest 1.3.90[zip] this didnā€™t connect at allā€¦
1.3.80 is what I have installed : this connects quickly does Mavlink ftp @param.pack
1.3.75 does attempt mavlinkftp but shifts to requesting individual sensor data.