qext-serial-port write problem.

[rex]

hello every one.. i have a small problem here. I am communicating with a hardware on rs232 serial terminal.. I am able to send a start of frame and receive back a acknowledge-ment from the hardware device. i am sending a fixed string i.e 0xAC,0xCA,0x1F as the start of the frame which the hardware device sud check for and give a ackn. which is working fine . this is what i am doing i am writing the string AC CA 1F to the port this is done successfully.i get a acknowledgment from the hardware also.

static const char mydata[] = { 0xAC,0xCA,0x1F};
	QByteArray data = QByteArray::fromRawData(mydata, sizeof(mydata));
	char i = port->write(mydata,sizeof(mydata));

static const char mydata[] = { 0xAC,0xCA,0x1F};
	QByteArray data = QByteArray::fromRawData(mydata, sizeof(mydata));
	char i = port->write(mydata,sizeof(mydata));

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Now the problem is when i try to send some configured hexa format data which i have
in QByteArray hexadecimaldata; i am splitting the each byte in it and putting them into firstByte and secondByte. cause i have to send the configured data byte by byte and the data is never more then 2 bytes.

firstByte = "0x"+hexadecimaldata.left(2);  
secondByte = "0x"+hexadecimaldata.mid(1, 2);            
char i = port->write(firstByte);
char i = port->write(secondByte);

firstByte = "0x"+hexadecimaldata.left(2);  
secondByte = "0x"+hexadecimaldata.mid(1, 2);            
char i = port->write(firstByte);
char i = port->write(secondByte);

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the configured hexadecimaldata is not wrting to the port..

Pls tell me if i am going wrong some wer. ?

thank you

[alainstgt]

have firstByte and secondByte been declared somewhere, and hexadecimaldata also been initialised?
Try also qdebug() << firstByte << secondByte; to check your values before sending them to the port.

[mcosta]

hi,

your code

firstByte = "0x"+hexadecimaldata.left(2);  
secondByte = "0x"+hexadecimaldata.mid(1, 2);

firstByte = "0x"+hexadecimaldata.left(2);  
secondByte = "0x"+hexadecimaldata.mid(1, 2);

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is strange.
you are pre-pending the sequence "0x" to your binary data.
this is what you want?

pay attention that you extract 2 bytes from hexadecimaldata with left() and mid()