Yes, the PRI is irrelevant. The NV setting you are looking for is written as part of the OEM vendor config. If you download the firmware package from whatever OEM vendor you got this modem from and unpack it, then you will find 3 different firmware parts (multiplied by the number of supported operators):
the actual firmware image, for example SWI9X30C_02.08.02.00.cwe
the operator specific NV settings and other operator files (PRI), for example SWI9X30C_02.08.02.00_GENERIC_002.007_000.nvu
the OEM specific NV settings, for example 1102662_9905046_EM7455_02.05.07.00_00_Lenovo-Laptop_001.003_000.nvu
The latter will contain the FCC auth related setting. I have not tried, so I cannot tell you whether the variable can be changed. But I believe it is likely if you know how to create or modify .nvu files. It might also be possible using other NVRAM modification methods. I don’t know…
Note that all three file types mentioned above are containers with an aribtratry number of different files and/or images. The firmware is responsible for unpacking them and interpreting the files within, and e.g. apply specific files as NVRAM variable updates given some condition. Exactly how this is done, the restrictions that apply and other necessary info, is probably only documented internally. Or possibly to OEM vendors as well? Regular end users like us don’t have access to it. But we can always guess
Yes, I believe that is by design. It is Non-Volatile…
You have to actively disable the setting. The regular NVU files won’t do that. And you might also have to replace the OEM NVUP file? That might also be persistent if written to flash before. I don’t know.
It would be great to know whether the tip from Rex_alex works.
But just FYI in case it doesn’t: You can send the QMI FCC auth request in MBIM mode. Look at how it is implemented in ModemManager/libqmi/libmbim. This Just Works with the recently released ModemManager 1.6.
I was trying this engineering mode for my EM7355 and it worked. My aim is to write the SAR BACKOFF settings permanently into the modem. Unfortunately even when I did the settings in eng. mode they were reverted to initial condition after changing the SIM and having the FW autoswitched to the carrier specific version.
Can you please help me how to do it steadily?
I also tried to apply the SARBACKOFF settings via the configuration.ini file, but that way they were not even set just once.
B4316 driver pack and windows 10 is used. Generic FW is 05.05.58.00. In the driver pack there is Verizon, ATT, Rogers, Sprint, Bell, Telus defined with their FW/nvu.
That was some years ago, OpenWrt had no umbim with QMI support (or uqmi was not able to send FCC, something of the two). FCC in umbim/uqmi was available some time later, so while still annoying, it worked. The original post was not in the OpenWrt environment obviously. Don’t know if ModemManager would have worked back then, haven’t tried it mainly because the device I was using had little flash memory - I think.
Not sure, it’s 1199:9079 now. It was in use on a OpenWrt device for some years (not any longer) and since I had it around without any use I inserted it into a Thinkpad T460 (Win 8.1). Although automatic driver installation went fine the device was still in LPM.
I got the device as a gift, my guess is that it was originally for a Thinkpad.