nRF52832 - DTM - transmit 2426MHz channel frequency only when set any different frequency channels in TX mode

[ou_frankie]

Hi All,

Enter to Direct Test Mode, the nRF52832 will transmit 2426MHz channel frequnicy only when set any different frequency channels (e.g. 2402MHz, 2418MHz) in the Tx mode

-nRFgo version: 1.21.2.10

Please help to advise how to solve this issue.

Best regards,

Frankie

[Andreas]

Hi,

 

Which channel do you enter when setting up the test? The TX frequency is determined as 2*channel+2402 MHz. Is it always set to 2426 MHz for all chanels? What SDK version are you using?

 

Best regards,

Andreas

[ou_frankie]

Hi Andreas,

1) For the test, the channel was set to any channels. e.g. Channel = 39. Based on your equation, the channel frequency should be 2*39 + 2402MHz = 2480MHz.

2) Yes, it is always transmit 2426MHz for all channels.

3) The SDK version is 14.2.0.

Do you have any idea for that? Thanks.

Best regards,

Frankie

[Andreas]

Hi,

 

Using a DK, I get TX on 2480 as intended when entering channel 39. Are you using a DK for the COM port interface or something else? Have you looked at the UART packets using a logic analyzer or oscilloscope?

 

Best regards,

Andreas

[ou_frankie]

Hi Andreas,

What is the DK? I am using the "USB to COM" dongle to control the nRF52832 PCBA which is lay by myself. What is the results / waveforms when I am using the oscilloscope at the UART packets?

My steps as follow.

1) I found a hex file (nRF52832_xxaa_DirectTestMode.hex) from the SDK 14.2.0.  (Refer to attached hex file)

2) And then I programmed this hex file to the nRF52832 IC.

3) Open the nRFgo and click the "Direct Test Mode" to control the channel in Tx mode.

Would you mind to help me for verify the attached hex file can control the channel in the Direct Test Mode?

Thanks.

Best regards,

Frankie

nrf52832_xxaa_DirectTestMode.hex

[Andreas]

Hi,

 

'The DK' is our development kit, it has a inferface MCU that among other things serves as a USB-UART bridge. Using this usually works fine, using other alternatives have a habit of causing various issues.

 

 

You need to look at the UART lines to see the communication being sent. The messages should be according to the DTM spec, section 3.3 in the attachment below describes this.

DTM_Spec_Core_v5.0.pdf

 

I ran the hex file on a development kit, and it works as it should. TX on assigned channel, not 2426 MHz.

 

Best regards,

Andreas

[ou_frankie]

Hi Andreas,

Thank you for your help.

I will troubleshoot this issue based on your information.

Best regards,

Frankie

[AmbystomaLabs]

If you are just doing in-house testing or FCC testing you might find radio_test easier to use than DTM. radio_test has a simple command line interface that you can access via a terminal session.

Support for DTM is only required if you are performing Bluetooth compliance testing.

radio_test is also in the SDK.