Hello.

I am working on a Project where I need to collect and logg data from a GPS. It is Connected to S7-1200 With RS-232. I have used a example Project earlier, but this time the GPS is more Advanced and use GPGGA and HEHDT.

It is no problem to read in one sentence from RS-232, but I can not find out how to read in the Next sentecne.

How do I read 2 different sentencens from RS232 using the Block RCV-CFG and RCV-PTP.

Or is it another way to do this easier?

Hope for good answere:) Thank you.

Best regards Andreas

Hello og thanks for feedback.

The GPS sends information automaticly. It is 3 sentence that are sends every 2 seconds.

Information that it sends looks like this:

$GPGGA,104315.00,4124.8963,N,08151.6838,E,1,07,1.5,280.2,M,-34.0,M,,*75

$GPZDA,104315.00,13,12,2017,00,00*60

$HEHDT,36.32,T*2B

Then it starts again. In my program I read in first sentence and stop with lineshift.

But I also want to read in Line: $HEHDT.

The GPS is Hemisphere MD Vector V103 GPS Compass, so the next line I want to read in is the compass.

Yes, it is true that it should be possible to read everything, but I am trying to create a "standard" block that can be connected to different types of GPS.

So I was looking for a solution where I was "listeing" for a sentence that start with $GPGGA and save this information to a string. Then it is listening for a sentence started with $HEHDT and then saved this in a string.

It is different possibilities on the CM1241 hardware config for "start sequence" and there is also some options on RCV_CFG under conditions where it is possible to change the start information.

But I can not find good documentation on how this is working in practic. I have tried different changes, but can not get it to work.

Andreas

andreas_CHE

The GPS sends information automaticly. It is 3 sentence that are sends every 2 seconds.

Information that it sends looks like this:

$GPGGA,104315.00,4124.8963,N,08151.6838,E,1,07,1.5,280.2,M,-34.0,M,,*75

$GPZDA,104315.00,13,12,2017,00,00*60

$HEHDT,36.32,T*2B

Then it starts again. In my program I read in first sentence and stop with lineshift.

But I also want to read in Line: $HEHDT.

The GPS is Hemisphere MD Vector V103 GPS Compass, so the next line I want to read in is the compass.

Hi,

This is probably a late answer, but there is an error in your end condition characters. You should set CONDITIONS.END.SEQ.STR[4] and CONDITIONS.END.SEQ.STR[5] instread of 1 and 2. In your way, RCV_PTP waits for CR/LF and any three characters after them. So, I suppose your RCV_PTP terminates with a timeout or waits next three characters from the next message and you do not get $HEHDT where you wanted.

See

SIMATIC S7 S7-1200, System Manual, v4.4, page 1036:

Example configuration: End message with a character sequence