nrf52 raw frames

[jeanjean]

Hi,

I want to workout a very simple custom wireless protocol, is it possible to send raw frames with the nrf52 ?
So not following the BLE standard and disable whitening.

Is there somewhere an example for it.

Thanks in advance!
Jan

[Priyanka]

Hi,

Letting you know that I am looking into it and will get back to you with a response soon. Please note that there might be a delay as we are currently short staffed owing to the summer holidays here in Norway. Thank you for your patience and understanding.

Best Regards,

Priyanka

[Priyanka]

Hi Jan,

Please take a look at this ticket and let me know if it helps.

-Priyanka

[jeanjean]

No, that does not help, I completely want to bypass the BLE standard.
I want to send a raw frame and try to receive it with a SDR on the other side.

Regards,
Jan

[Priyanka]

Hi Jan,

I will check this internally and get back to you.

-Priyanka

[Priyanka]

Hi Jan,

Please take a look at this https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/esb/README.html 

There are also a few simpler samples in the previous (nRF5) SDK :

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/nrf_dev_radio_tx_example.html?cp=9_1_4_6_30 

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/nrf_dev_radio_rx_example.html?cp=9_1_4_6_29 

-Priyanka

[jeanjean]

Thanks, that is exactly what I need !

The radio tx example works for me:
Looks like its transmitting one byte, do you know the format ?
Is it just the BLE preamble and the data byte ?

| preamble | databyte |

Other question: does the sniffer have some raw mode, like just sniffing on a ble channel and show also invalid ble frames ?

Thanks,

[Priyanka]

Hi Jan,

The radio configuration is done according to radio_configure() function (components\drivers_nrf\radio_config\radio_config.c).

The payload is a single uin32_t variable:

Not sure if the length is set, or if it will actually transmit PACKET_PAYLOAD_MAXSIZE. It seems that the length field in the packet is 0:

I am afraid I'm not aware of any raw modes to capture proprietary packets using the sniffer. The default mode of the radio tx example is NRF1M, not BLE1M used by the sniffer.

Also, the payload will be set according to some button press:

-Priyanka