MC7455 Bug with SMS and GPS

When NMEA GPS data is being sent to the NMEA port (initiated with a “echo $GPS_START >/dev/ttyUSB1”), the +CMGS command will not work to spec.

If the GPS sessions are stopped using !GPSEND=0,255, then the +CMGS command works as it should.

The issue is the response from the +CMGS command.

With GPS running we get:


Without GPS running, we get (and is correct):


Both ways will then accept the PDU, and send the SMS, but with GPS on, no +CMGS response is received, with GPS off, the response is received as it should be.

We are running SWI9X30C_02.24.03.00

Another person with an MC7430 also tested this, and has the same issue, so seems to be across multiple products.

Not sure who needs to be told about this, so hopefully someone from SW see this.

This problem needs a detailed technical analysis. Please contact your Technical support in SWI to provide you the solution.

Thanks & Regards,

Will try to contact distributor for assistance.

Also to document, another command that does not work properly with NMEA stream running:


With NMEA running, it simply returns OK.

With NMEA/GPS turned off, it responds as expected.