HELP! UART4 with Skywire cape lite not working properly


I’m having trouble with the Skywire cape lite. A Nimbelink GPRS module is plugged in.
I’m not receiving the OK response to the AT command (or to any other AT cmd) when I run
a basic tx rx application on the beaglebone. However I get the OK response when I’m
connected through a terminal (pico, putty).

If you are familiar with the cape it communicates through UART4. The cape also has a
uart grove connector connected to UART5 which I use to communicate with some other

Here’s what I’m seeing =>


  • the grove connector (UART5) is connected to some other module
  • pico is connected to UART4
  • the app initializes UART4 as well


  • run the basic application


  • the AT cmd and OK response echoes on the terminal
  • No OK response in the application