Attachments (0)
Nordic Case Info
  • Case ID: 279034
Options
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

UART Question (Pull-up configuration)?

eiadj

Hi,

We have some questions from one of our FW guys regarding the configuration of the UART pin:

I looked at the UARTE driver implementation, it configures the UART Rx line with a no-pull resistor configuration.

Questions:

  1. Why does the driver configure the UART RX line with a no-pull configuration?  If the UART port is left unconnected, this may cause the UART driver to report unexpected communication errors.
  2. When the UART port is left unconnected, does the driver expect the Rx line to be pulled up externally?
  3. Is it okay to modify the driver, i.e., the function apply_config, to configure the UART Rx with an internal pull-up resistor?

Reference:

I found a similar issue on Dev Zone:

https://devzone.nordicsemi.com/f/nordic-q-a/25591/uart-hits-communication-error/100873#100873

 

The goal is to have the UART work when connected but avoid errors when not connected. Can you guys address the questions and explain why the Nordic driver configures it that way?

Thanks!

Terms of service