Reading COM port in c++, getting errors - c++

Question

First time poster long time reader.
I've been playing round with reading in data from a bluetooth GPS unit.
I can connect to it using hyperterm and see the data
The following log is from the hyperterm
$GPRMC,195307.109,A,5208.2241,N,00027.7689,W,000.0,345.8,310712,,,A*7E
$GPVTG,345.8,T,,M,000.0,N,000.0,K,A*07
$GPGGA,195308.109,5208.2242,N,00027.7688,W,1,04,2.1,58.9,M,47.3,M,,0000*7E
$GPGSA,A,3,19,03,11,22,,,,,,,,,5.5,2.1,5.0*3F
$GPRMC,195308.109,A,5208.2242,N,00027.7688,W,000.0,345.8,310712,,,A*73
$GPVTG,345.8,T,,M,000.0,N,000.0,K,A*07
$GPGGA,195309.109,5208.2243,N,00027.7688,W,1,04,2.1,58.9,M,47.3,M,,0000*7E
END LOG
The following log is from my C++ program
$GPGSV,3,3,12,14,20,105,16,28,18,323,,08,07,288,,16,01,178,*7A
$GPRMC,195,3,2ÿþÿÿÿL.š945.109,A,5208.2386,N,00027.7592,W,000.0,169.5,8,323,,08,07,288,,16,01,178,*7A
$GPRMC,195,3,2ÿþÿÿÿL.š310712,,,A*70
$GPVTG,169.5,T,,M,000.0,N,000.0,K,A*06
8,07,288,,16,01,178,*7A
$GPRMC,195,3,2ÿþÿÿÿL.š310712,,,A*70
$GPVTG,169.5,T,,M,000.0,N,000.0,K,A*06
8,07,288,,16,01,178,*7A
$GPRMC,195,3,2ÿþÿÿÿL.š$GPGGA,195946.109,5208.2386,N,00027.7592,W,1.0,K,A*06
8,07,288,,16,01,178,*7A
END LOG
THE PROBLEM
I've left the line feeds as they come, the C++ output has extra line feeds, not sure why?
The C++ log also has some funky chars...?
The Code
for (int n=0;n<100;n++) {
char INBUFFER[100];
cv::waitKey(1000);
bStatus = ReadFile(comport, // Handle
&INBUFFER, // Incoming data
100, // Number of bytes to read
&bytes_read, // Number of bytes read
NULL);
cout << "bStatus " << bStatus << endl;
if (bStatus != 0)
{
// error processing code goes here
}
LogFile << INBUFFER;
}
I'm using settings...
comSettings.BaudRate = 2400;
comSettings.StopBits = ONESTOPBIT;
comSettings.ByteSize = 8;
comSettings.Parity = NOPARITY;
comSettings.fParity = FALSE;
...which as far as I can tell are the same as the settings used by hyperterm.
Any hints on what I'm doing wrong?
cheers!
UPDATE
So after updating to use bytes_read and account for the extra LF at the end of NMEA data I now have...
if (bytes_read!=0) {
for (int i=0; i < bytes_read; i++) {
LogFile << INBUFFER[i];
}
}
Which appears to have fixed things!
$GPGGA,215057.026,5208.2189,N,00027.7349,W,1,04,6.8,244.6,M,47.3,M,,0000*41
$GPGSA,A,3,32,11,01,19,,,,,,,,,9.7,6.8,7.0*3D
$GPRMC,215057.026,A,5208.2189,N,00027.7349,W,002.0,208.7,310712,,,A*74
$GPVTG,208.7,T,,M,002.0,N,003.8,K,A*09
$GPGGA,215058.026,5208.2166,N,00027.7333,W,1,04,6.8,243.1,M,47.3,M,,0000*42
Thanks folks, your help was much appreciated.

Answer 1

You have a bytes_read var, but you don't do anything with it? Seems to me that you're dumping the entire INBUFFER to the file, no matter how many/few bytes are actually loaded into it?