%XRFTEST LTE-M error 8

[wne]

Hi,

I have an issue with using the %XRFTEST command for TX testing on the LTE-M network.
My setup consists of the nRF9160 DK (PCA10090) with the MFW 1.2.3 and a 1NCE SIM.
I have already verified that I can establish a LTE connection in systemmode NB on band 8 and in systemmode M on band 3 and band 20.
Now I am about to test the TX perormance in both systemmodes and on every respective band.

So when I use the AT command AT%XRFTEST=1,1,8,9000,10,0,4 the response is %XRFTEST: 157. Everything works fine here.
If I use the AT command AT%XRFTEST=1,1,20,8000,10,1,4 the response is always a timeout in at_client and error 8 in my own firmware.
I have also tried band 3 with LTE-M with the same result. The error means "exec format error" but I can not find the failure in my command format.
I hope you can tell me what I am doing wrong.

Best regards

[Håkon Alseth]

Hi,

 

If I use the AT command AT%XRFTEST=1,1,20,8000,10,1,4 the response is always a timeout in at_client and error 8 in my own firmware.
I have also tried band 3 with LTE-M with the same result. The error means "exec format error" but I can not find the failure in my command format.
I hope you can tell me what I am doing wrong.

The band frequencies for uplink/downlink is shown here:

https://en.wikipedia.org/wiki/LTE_frequency_bands

 

For setting a uplink (ie: a carrier output from nRF9160), you should start from 832 MHz:

AT%XRFTEST=1,1,20,8320,10,0,4

 

Could you try this?

Note that you are outputting power in a restricted band by issuing the above command. This shall only be done in a shielded environment!

 

Kind regards,

Håkon 

[wne]

Hi Håkon,

thanks for your response, the command AT%XRFTEST=1,1,20,8320,10,1,4 results in a valid response (%XRFTEST: 180). I did not think that the frequency has to be that accurate, but now I know.

So thank you very much.