Need Information On UART

mangOH Green
3

Hello again CSLEE,

Although my previous message is accurate, I don’t think it will solve your problem. I forgot that UART 1 may not even be under control of the application processor. In order to give control of UART 1 to the application processor we need to send an AT command to the modem.

The mangOH Fundamentals - Linux CLI document describes how to send an AT command in section “7.1.2 Connect to AirVantage” on page 28.

In our case we want to send a different AT command. The AT command we want to sent is briefly described on this Legato HOWTO - Customize UART page.

No documents, just the instructions!

  1. in a terminal on the mangOH, run microcom -E /dev/ttyAT
  2. type the command AT!MAPUART? to show the current UART configuration. The value is interpreted as UART1Routing,UART2Routing.
  3. type the command AT!MAPUART=17,1 to route UART1 to “Customer Linux application”
  4. type in the command AT!MAPUART? to confirm that the setting has changed
  5. press ctrl-x to exit microcom
  6. enter the command reboot -n to reboot the system

Now UART 1 should be available for use by your application. It will default to Iot slot 0, but you can use the instructions from my previous message to disable UART1 or route it to IoT slot 1.

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