%RFTEST returns a "Error: %XRFTEST=1,1,13,7820,0,1,4 failed: phone failure"

[Mike]

Hi,

We just recently bought the nRF9160_DK board and compiled and loaded the AT_Client onto the DK. We have followed all the setup instructions for the SIM card for iBasis hosting. We are able to power up the DK and it is able to connect to a Verizon network using the nRF Connect v.2.6.2 Link Monitor. The LTE Link Monitor is showing all green for UART, MODEM, UICC, LTE, and PDN. The LTE Link Monitor is also showing CS/PS mode 2, bands available are 3,4,13,20, the current band shown is 13.

We wanted to run the %XRFTEST command on the DK while connected to a spectrum analyzer to evaluate TX and RX performance. Per the "nrf91_at_commands_v0.7.pdf" document a %XRFTEST command for TX follows this syntax:

%RFTEST=<test>,<operation>,<param0>,<param1>,…,<param7>

<test>=1 for TX testing

<operation>=1 for enabling testing

<param0>=13 for 3GPP band number 13

<param1>=7820 for frequency 782.0 MHz

<param2>=0 for TX signal power at antenna of 0dbm

<param3>=1 for system mode of LTE-M

<param4>=4 for CW modulation

When I issue this command the LTE Link Monitor shows the message:

"Error: %RFTEST=1,1,13,7820,0,1,4 failed: phone failure" 

What does this message mean? What setting have I misunderstood?

Thanks

[Mike]

Update to this post:

The "nrf91_at_commands_v0.7.pdf" document is not correct for the syntax for this command:

The syntax lists %RFTEST which is what we were using and getting an error thrown by the DK.

When we used the below syntax:

AT%XRFTEST=1,1,13,7820,0,1,4

We no longer get a phone failure message.

The example should've been %XRFTEST=… not %RFTEST=….

Now that we are able to run the %XRFTEST we are seeing a new error.

We power up the DK

The AT host is running on the DK

The DK connects to the Verizon network

We issue the AT%XRFTEST=1,1,13,7820,0,1,4 command and the DK responds back with %XRFTEST: -795

We attach the MXHS83QE3000 connector to the DK and our spectrum analyzer

The DK shows loss of signal quality by reporting:

%CESQ: 12,0

%CESQ: 7,0

%CESQ: 1,0

+CEREG: 5,"FFFE","FFFFFFFF",7

AT+COPS=3,2

OK

AT+COPS?

+COPS: 0,2,"311480",7

OK

AT+CGDCONT?

+CGDCONT: 0,"IP","ibasis.iot","10.160.160.218",0,0

OK

AT+CGACT?

+CGACT: 0,1

OK

We issue the AT%XRFTEST=1,1,13,7820,0,1,4 command again and the DK responds back with:

Error: 'AT%XRFTEST=1,1,13,7820,0,1,4 ' timed out

Is there a time limit allowed between issuing successive commands? What is the DK timing out on? Once it throws the error all other AT commands throw a timeout error.  

Thanks

[Martin Lesund]

Hi Mike,

First, Thank you for reporting the misspelling of the command. It has been reported internally.

* Please make sure to uncheck the "Automatic requests" in LTE Link Monitor:

To use it as a standard serial terminal and avoid the AT-Command script running in the background.

---

You should not need to run any other AT command than AT%XRFTEST=1,1,13,7820,0,1,4 first right after you reset the DK.

Note that these commands shall not be used unless in a shielded environment.