AT Command(s) for PRL (Preferred Roaming List)


Hello All!

I have a Sierra MC7455 on Sprint network. I am trying to figure out how to query PRL and run update on it.

I found that there is a command “at$PRL?” which will return to me “$PRL: NOT IMPLEMENTED”.

Does anybody know how to implement PRL on this module and the command to update it? I have read that “+PRL=2” can be used to run PRL update but I have been unable to get this to work due to the error above.

Any guidance would be greatly appreciated!

Thank you in advance.


MC7455 doesn’t support CDMA so the PRL will not be relevant anymore. That’s why the PRL command was not implemented.



So assuming you have a 7455 on the network you will have a preferred operator list, which in effect is a preferred roaming list, on the SIM which is managed by the operator, you can read this using the standard 3GPP at+cpol command.




@mlw thanks so much for the response.

I’ve just tried this and I get the following error:

response: +CME ERROR: operation not allowed.

Note: I did use at!entercnd=“A710” to give me admin and still got the same response. Also it is an active SIM card and registered status on Band 25 when i run at!gstatus?

Any ideas? Thanks much in advance!



Yes I have tested and get the same result which is surprising given the manual states that it is supported. Not sure what to suggest as this was the command that should have done the job and it looks like it is not implemented properly in the firmware.

I tested on the MC7455 if failed then moved the SIM to another (HL series) and it read the list out using this command so there was definitely one on the SIM card.




AT+CPOL is a 3GPP command to query PLMN where PRL is specifically for CDMA which follows 3GPP2 spec. Back to the original question about AT$PRL, it’s a legacy AT command from Qualcomm in order to query Preferred Roaming List for CDMA carriers. MC7455 doesn’t support CDMA hence no PRL to be implemented or updated.