string

[David Crow]

macmac38 wrote: yep, it seems to be better to use a reference. My example was not a reference. It was a pointer, exactly what the Read() method is expecting. Had it wanted a reference, the signature would look like:

BOOL Read(void& lpBuf, ...);

You mentioned that 924.09,-4.06,676.26,0.156488,-0.653856,-0.714853,-0.192273 is arriving at the serial port. How are you verifying this?

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

[macmac38]

This is the position string from a robot arm and every time the same format. x,y,z shift and quaternion 1-4 I have to extract them later from the string in float variables Thanks, Mark

[David Crow]

That's all well and good, but in your original post, you indicated that "This arrives at my serial port," implying that the data is indeed there. That's why I asked how you were verifying it. In the while loop that you are using to read the incoming data, how many times does the loop execute? After each call to Read(), what is the value of dwBytesRead? If the incoming data is always in the same format and is always less than X bytes, you might could use this instead:

char received[X];
port.Read(received, sizeof(received), overlapped, &dwBytesRead);
received[dwBytesRead] = '\0';

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

[macmac38]

received[dwBytesRead] = '\0'; what does this line mean? I have "access violation" with this line. Thanks, Mark

[David Crow]

macmac38 wrote: what does this line mean? It appends a \0 character to the end of the string. macmac38 wrote: I have "access violation" with this line. How big is the received array, and what is the value of dwBytesRead?

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

[macmac38]

char received[40]; port.Read(received, sizeof(received), overlapped, &dwBytesRead); TRACE( "Bytes read: %d",dwBytesRead); received[dwBytesRead] = '\0'; SetDlgItemText(IDC_SHIFT_X, received); Bytes read: 1Bytes read: -858993460Bytes read: -858993460Bytes read: -858993460 Thanks, Mark

[David Crow]

macmac38 wrote: TRACE( "Bytes read: %d",dwBytesRead); Since dwBytesRead is a DWORD, you'll need to use the %lu format. Nonetheless, if received[] is only 40 bytes, trying to access the -858993460th position, or any value outside of 0-39, is obviously wrong. Check the return value of Read() beforehand. In your original post, you indicated that 58 characters were being sent to the serial port. You'll need room for that plus one more so received[] should be 59 not 40. This is not the root of the problem, however, but will eventually need to be addressed.

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

[macmac38]

char received[59]; port.Read(received, sizeof(received), overlapped, &dwBytesRead); TRACE( "Bytes read: %lu",dwBytesRead); received[dwBytesRead] = '\0'; SetDlgItemText(IDC_SHIFT_X, received); Bytes read: 1 I donn't know where's the problem? Normaly it seems easy..? Like to solve it today ;-) Thanks, Mark

[David Crow]

macmac38 wrote: I donn't know where's the problem? Are you sure a problem exists? Maybe there was only one byte available to read.

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

[macmac38]

But this Byte output like: j which means no character in it? But the full string is arriving.. if i don't use this line: received[dwBytesRead] = '\0'; the output is: -0.714853,-0.192273jjjjjjjjjjjjjjjjj Thanks, Mark

[David Crow]

macmac38 wrote: But the full string is arriving.. How are you verifying this claim? Whct class does the Read() method belong to? I'm curious if the fourth parameter is being used correctly. If more than one byte is being read, yet dwBytesRead equals 1, something is awfully wrong. It might also be the third parameter, but I've never used the OVERLAPPED structure before so I can't say for sure.

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"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)