Changing UART defaults in custom image

Hi all,

I am creating a custom firmware image that bundles in our custom application. The only hangup is I need UART1 to be configured for Console access and UART2 for Linux App access. What do I need to do to make that the default?

Depends on which product you are using, normally it can be configured using AT!MAPUART command during production or in the app.


This setting is persistent and takes effect on power cycle, but also recommend to use !NVBACKUP to save it as factory default.

Hope it helps.

Thank you for your response.
We are using the WP7603-1
I am currently using AT!MAPUART or uartMode to set the mapping on our development boards. For production however we want a custom image that has all of our settings including the UARTmapping “out of the box” so that the programming time on the production line can be minimized. Is the UART mapping a Legato construct that can be tweaked with a custom Legato build?

Sorry to miss your reply.

To my understanding, the UART mapping is not decided by Yocto.
A possible way maybe implement !MAPUART command in app or Yocto init script so to configure the desired value automatically.

Hope it helps.


can you provide some details about how we can implement !MAPUART in app or Yocto init script?


You can do mapuart in app with le_atClient.
You can also do it with a system call - system(“mapUart set 1 app”).

Personally I have an expect script which ssh’s in and performs some config before I install my system with fwupdate.

Yes, UART can be configure using the application, See i have attached the sample (2.1 KB)
where you can configure the UART.

Muralidhara N.