micro 1400

[dmelect]

How can I tell if a message instruction that I have written is reading data? I dont see any errors but I dont know if it is reading the data comming into the micrologix.

 

[dmelect]

I am using RSlogix500 software

 

[bernie_carlton]

Just before invoking the MSG command clear the target registers (if that is safe). When the MSG command indicates DN and no errors then examine the target area. if it is still clear then either there was no data or you aren't getting what you thought.

 

[dmelect]

sorry need a little help target registers?
Dumb question maybe

 

[Mickey]

sorry need a little help target registers?
Dumb question maybe

Post your program, the .RSS file ( zip it first) then tell us which message instruction you are having trouble with and someone will help you.

 

[dmelect]

Ok its pretty simple just trying to get some equipment talking to a 1400.

 

[bernie_carlton]

In the message instruction is a portion which specifies where the received information is to be stored.

 

[daba]

In my experience, the message .DN bit being set indicates a completely successful data transfer....

If the data in the destination appears wrong, you may have to look see if something else is writing to the same destination.

 

[dmelect]

OK thanks I will keep working on it.

 

[Mickey]

See picture below. Your data will be in N7:0 thru N7:9.

What are you connected to ( read from)? And how are you connected to it.

 

[dmelect]

I am connected to a Garmin GPS reciever through an rs232 into the micro1400

 

[Ken Roach]

Aha !

A Garmin is going to be sending out strings of NMEA 0183 format data, and you're going to need to be able to parse it with the ASCII functions of the controller, not the MSG instructions.

Do you have an example of the data stream from this particular GPS ? Does it allow a query/response mode or streaming data only ?

 

[dmelect]

I will check on that right now, thanks

 

[dmelect]

It says in Binary output mode it will transmit packets once per second. Does that help

 

[Ken Roach]

That's good.

The first thing I would do is hook up the Garmin to my computer and run Hyperterminal or another terminal program (TeraTerm and RealTerm are my favorites).

This will let you see the actual NMEA Sentences coming from the device, so you have something to compare the incoming data in the MicroLogix to.

http://www.gpsinformation.org/dale/nmea.htm#position

Are you trying to get position, or navigation, or time, or something else ? Is this an automatically guided vehicle application, or a mining application, or a vessel ?