[PHS8-P] Activate before ATD*99#? | Telit Cinterion IoT Developer Community

Hi,

I'd like to improve diagnostic output under bad mobile signal conditions, therefore want to AT+CGACT=1,1 explicitly before the ATD*99***1# instead of have it done implicitly by ATD.

My hope is to get more detailed error codes from AT+CGACT instead of having the PPP dialog time out when PDP context setup fails.

However when I add AT+CGACT=1,1 between AT+ATTN=1 and ATD*99***1#, the latter fails, apparently because the context is busy. Documentation for ATD*99# says it will activate the context implicitly if needed, so I hadn't expected it to fail with an explicitly activated context. ("PS attachment and PDP context activation procedures may take place prior to or during the PDP startup if they have not already been performed using the AT+CGATT and AT+CGACT commands.")

I can get the data connection back to working by deactivating the context (AT+CGACT=0,1) after activating it and before ATD, but obviously I would like to avoid a setup/teardown/setup sequence for each connection, and also the explicit setup action is not the same as the second, implicit one in this case.

What would be the proper way to achieve this?