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Thread: QSerialPort :: read - Serial Comms noob.

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    Default QSerialPort :: read - Serial Comms noob.

    Hi - I am using QSerialPort to talk to a Basic Stamp microprocessor spitting out 2 byte values (pbasic WORD) read from an accelerometer.

    I am a complete serial comms noob.

    I am able to set up the comms fine, but I'm not sure what exactly CSerialPort :: read() gives me when passed an array of char.

    So

    bytesRead = SerialPort.read( bytes, 50 );

    reads up to 50 chars into the array specified by "bytes". But what those bytes? The port is set to readonly, 9500 baud, 8 data bits, no parity bit, one stop bit, no flow control.

    Are the bytes read those read off the serial port as is, i.e., 1 start bit, 8 data bits, one stop bit (So that the frame is split across multiple bytes, and my 2 byte word is split across 3 bytes)

    Or is the char the data bits only (and my 2 byte word is split across 2 bytes only ?)

    Thanks

    Griff

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    Default Re: QSerialPort :: read - Serial Comms noob.

    It is the data only.

    You probably should not be using read(), just readAll() in the slot you connect to readyRead().

  3. The following user says thank you to ChrisW67 for this useful post:

    llaregyb (8th January 2014)

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    Default Re: QSerialPort :: read - Serial Comms noob.

    So my WORD from the stamp will be returned as successive bytes.

    I'll consider readAll - currently, it's at the 'hack' stage, and it's just running in a subthread.

    Thanks for your help.

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