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Stranges characters first ready read qserialport Linux or mac

  • I have probem with qt qserialport
    5.5 or 5.6.
    With a terminal project exemple.

    Sometimes at start in first ready read. Characters is stranges
    Lot of characters incorrectly

    I have platform why send 28 bytes

    with 5aa5 at begining.

    Linux or mac same problems

    With Windows works with the same project.

    No characters available after open
    But in ready read receive incorrectly characters

    Please Help.

  • I think you should try clearing port after initialization like:

    QSerialPort *port = new QSerialPort(); 

    You can read more about it here:

  • no change because no character available after open.

    in my mac:

    connecté: "cu.usbserial-FTB4CPZG"
    Recu : "5aa591327210074b3800190000000000000000000000c8000001014e5aa592327c10074b3800160000000000000000000000c700000101475aa593328610" len: 62
    Recu : "5aa5dead7410074b3800160000000000000000000000c70000010188" len: 28
    Recu : "5aa5dfad7e10074b38" len: 9
    Recu : "00180000000000000000000000c8000001017a" len: 19
    Recu : "5aa5" len: 2
    Recu : "e0ad8810074b3800180000000000000000000000c8000001016f" len: 26
    Recu : "5aa5e1ad9210074b3800180000000000000000000000c700000101" len: 27
    Recu : "65" len: 1

    with clear:
    nb bytes avaible before open 0
    nb bytes avaible after open with clear() 0
    connecté: "cu.usbserial-FTB4CPZG"
    Recu : "a5 fe aeb410074b3800180000000000000000000000c70000010125
    5aa5 ff aebe10074b3800180000000000000000000000c7000001011a
    5aa5 00 aec81007
    5aa5 00 fec810074b3800140000000000000000" len: 81

    first packet is all the time wrong....!!!!
    it's crazy....!
    byte after 5aa5 represent counter frame of protocole

    2 frames have the same id!

    Recu : "000000c800000101c2" len: 9

    Recu : "5aa501fed210074b3800140000" len: 13
    Recu : "000000000000000000c700000101b8" len: 15

    Recu : "5aa502fedc1007" len: 7
    Recu : "4b3800160000000000000000000000c800000101aa" len: 21

    Recu : "5aa503fee610074b3800160000000000000000000000c700000101a0" len: 28

    all is wrong:
    nb bytes avaible avant open 0
    nb bytes avaible apres open 0
    connecté: "cu.usbserial-FTB4CPZG"
    Recu : "83090d610a0000080000000a006083080c610601000000000009006083080f6106010000000000090020832900610602000000000009008033290b610e01" len: 62
    Recu : "5aa5e8e7d810074b3800180000000000000000000000c70000" len: 25
    Recu : "0101de" len: 3
    Recu : "5aa5e9e7e210074b3800180000000000000000" len: 19
    Recu : "000000c800000101d2" len: 9

    i clear after open,
    i clear before close.

    software coolTerm have same Problem... linux problem???