Lighthouse has a new layout. Prefer the old one? Return to the old layout, and switch back any time from the link at the top of each page.

Header checksum mismatch: expected 0x0369

#3

Getting header checksum mismatch errors this morning (8/23) when trying to connect to REF001 A/C.

-[BTRLinkDriver processFrame:] [Line 439] Header checksum mismatch: expected 0x5A2D calculated 0x712B (error for REF001-C) -[BTRLinkDriver processFrame:] [Line 439] Header checksum mismatch: expected 0x0369 calculated 0xFB22 (error for REF001-A/B)

Able to connect to other reflectors fine, like REF035-C and REF029-C.

Should this type of thing be bubbled up to the user? I am now running console all the time, filtering for Buster messages. (Because I am that weird)

Reported by Kenny Richards · August 23rd, 2015 @ 10:45 AM

State: pending
Milestone: none
Assigned to: mcdermj (at xenotropic) mcdermj (at xenotropic)

Activity

  1. mcdermj (at xenotropic)
    mcdermj (at xenotropic)
    • State changed from new to open

    This isn't really a connection issue per se. Each D-STAR header frame has a checksum over it. It's part of the D-STAR over-the-air specification. It's not involved in frames with AMBE data, only frames with header data. I'm assuming this is because the AMBE data already has FEC applied, so a checksum is really overkill. These are technically bad packets according to the spec. I did see some notes in Johnathan's code, though, that implied that D-Plus checksums are "unreliable" (See https://github.com/dl5di/OpenDV/blob/master/ircDDBGateway/Common/DP...).

    This isn't really something that the user can do anything about. Either the header is per spec, or it's not, so it's not really appropriate to percolate up to the user.

    Currently Buster discards header packets with a bad checksum. What should probably be done is that for D-Plus, we should warn about those packets only and not discard them. This is what ircDDBGateway does.

    August 23rd, 2015 @ 01:24 PM

  2. mcdermj (at xenotropic)
    mcdermj (at xenotropic)
    • State changed from open to pending

    Implemented optional checksum checking.

    Git 360df18.

    August 24th, 2015 @ 02:13 PM

  3. mcdermj (at xenotropic)
    mcdermj (at xenotropic)

    Included in 1.0.1d103, now available for download at http://www.nh6z.net/Files/Buster.zip

    August 24th, 2015 @ 02:56 PM

Please Sign in or create a free account to add a new ticket.

With your very own profile, you can contribute to projects, track your activity, watch tickets, receive and update tickets through your email and much more.