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  1. Qt
  2. QTBUG-53171

Incorrect / missing display of received messages

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Details

    • Bug
    • Resolution: Done
    • P2: Important
    • 5.6.2, 5.7.1
    • 5.6.0
    • SerialBus: CAN Bus
    • None
    • Linux
    • 55ad040de1ac6a33b4f2efe29038e97e8d43dbc2 4cd1146041e788ceb1d8fb283f5257e743579843 0317755dc0bc3d8bebe838f0715c14ed63173f38 aa4222f350a59ad2d90f14a1dfb88f83bf2d2c78

    Description

      Both the CAN Example and the canutil have problems displaying incoming frames.

      • CAN Example
        • Silently drops messages with DLC = 0
        • Does not distinguish between messages with Std. (11 bit) and Ext. ID (29 bit)
      • canutil
        • Does not distinguish between messages with Std. (11 bit) and Ext. ID (29 bit)

      Technical background: CAN-Messages with the "Extended" flag are transmitted with 29 bit identifier, even if the ID would fit into a Standard frame. This is how candump and canutils displays the message:

      candump: fills with zeros to show this is an extended frame
        can0  000007FF   [0]
      
      canutil: the information about extended ID is gone
        Id: 7ff bytes: 0 data:
      

      Expeced behavior:

      • Messages with Extended ID should be marked so
      • Messages with DLC = 0 should be displayed
      • Remote request could be displayed like candump does:
         can0       123   [0]  remote request
         can0  000007FF   [8]  remote request
        
      • canutil displays remote requests with DLC > 0 like this, which is wrong as the message does not contain data:
         RTR: Id: 7ff bytes: 8 data: 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0
        
      • candump also pretty aligns the messages in a table:
          can0  00000800   [8]  11 22 33 44 55 66 77 88
          can0       004   [1]  C8
          can0       004   [1]  CC
          can0       123   [0]  remote request
          can0       123   [0] 
          can0  000007FF   [0] 
          can0  000007FF   [8]  remote request
        

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            aha_1980 André Hartmann
            aha_1980 André Hartmann
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            Dates

              Created:
              Updated:
              Resolved:

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