Legacy PCO mode in nrf conect SDK 1.7.1

[Vassilis]

Hi

I am evaluating nrf9160 with an nrf9160-DK on nb-iot in Greece. I am using the asset tracker application example.

I have an issue of DNS not resolving that is expressed with the  "getaddrinfo, error: -11" error in the debug info.

While using an engineering sample DK with SDK 1.4.0, following recommendations found on other posts I set the Legacy PCO mode and that solved the problem. I was able to connect to nrf Cloud and transfer data.. 

Now that I've got an new DK I am trying to use the latest SDK and modem firmware and I have the same problem.

Unfortunately it seems that this configuration option is not available in SDK 1.7.1   

Is it moved under another name ?

How can I overcome this?

[helsing]

How did you set the Legacy PCO mode?

Did you try the following(XEPCO)?

AT%XEPCO=0

[Vassilis]

In SDK v1.4.0 there is configuration option <LTE_LEGACY_PCO_MODE>  in the LTE link control library Kconfig.

I've set it from there with the SEGGER Embedded Studio Configurator tool by checking the "Enable legacy LTE Protocol Configuration Options" checkbox...

This is what I am looking for and I can't find in SDK v1.7.1 

[helsing]

What happens if you fire the following?

AT%XEPCO=0

[Vassilis]

It works, and as I can save it by sending the AT+CFUN=0 command after the setting, I have overcome my development needs so far.

But for production I need a way to send it from firmware... The SDK 1.7.1 seems to not handle at all this command at configuration level.. 

Possibly it is in order to allow for flexibility to do it in run time, but then where is the most suitable place in code to add it programmatically?

[helsing]

Thank you for the update, this sounds promising.

You may use the command at the beginning of your application by using at_cmd_write(). An alternative is to add 'CONFIG_PDN_LEGACY_PCO=y' to your prj.conf file.

For reference: CONFIG_PDN_LEGACY_PCO