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URC interrupted by AT command result (MC55i) | Telit Cinterion IoT Developer Community

October 16, 2015 - 1:35pm, 2184 views

Hi,

I'm using a MC55i module which has been modified by Triorail to support the GSMR frequencies. I use this module to receive diagnostic SMS from our trains.

My problem is that the URC +CMT (derect forwarding of incoming SMS) sometimes gets interrupted by the result of a previous transmitted AT command.

For example:

tx: AT
rx: +CMT: ,94
07913364819009F6240B912364813036F8000051016110452080554D196D149C8D642FD9C859653E87A01C0C8783C168B55B6C347D3A9FA0D828E9A416A5C36713141B05AAT
OK
B41106C448D4CAF91A7D108B2C146D4C810199966A720DC88983C468A4E106E3402

The 'OK' respons from the AT command is in the middle of the received PDU code. Also the AT echo of the command is missing?

I have echo turned on and wait 100ms after sending a command just like the datasheet describes but it's still interrupting the URC code.

I wonder if there is any way to prevent this from happening?