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[SOLVED] SIM5360A UART conflict between AT COMMAND and NMEA

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Oct 6, 2015
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I have a similar problem as the thread

I develop upon SIM5360-EVB_V1.03 and communicate through the UART (RS232) and UART2 (micro USB) to configure SIM5360. I want to develop a specific board with this chip and using only UART (RS232) as serial port to communicate AT commands and receive NMEA sentences. I did not read this was not possible, but I did not achieve doing it. I configured SIM5360 to allow either the transmission of AT commands through UART port or the reception of NMEA sentences. I would like to do both with the same port.

The following configuration allow to receive NMEA sentences only:
AT+CMUXSRVPORT=1,1   //DATA through virtual port 1
AT+CGPSSWITCH=2        //NMEA through UART port

The following configuration allow to transmit AT commands only:
AT+CMUXSRVPORT=1,5   //NMEA through virtual port 1 (NMEA port)
AT+CGPSSWITCH=1        //NMEA through NMEA port

From, I understand that uploading the factory reset firmware with the QDL utility could be a solution in case we corrupted the current firmware by inadvertence.

Does someone has a solution or has the SIM5360A factory reset firmware?

According to the SIMCOM Technical Support:

1) Command AT+CMUXSRVPORT is used to make physical UART interface for few virtual ports after AT+CMUX=1 enabled. And for host, there should be some special driver for linux/window OS.
2) Command AT+CGPSSWITCH is used to switch NMEA sentence output between USB –NMEA port (after install driver in windows, you can find Modem port, Diag port, NMEA port and AT port) and physical UART port.

So, if you don’t use CMUX, just connect physical UART interface, recommend AT command to inquiry GPS location, do not switch NMEA to UART. If you use USB interface of module, just get GPS NMEA output from USB-NMEA port by defatult. No need to switch.

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