ESB 2.4GHz

[wzszzxj]

HI，ALL：

       How to setup TX mode  in example PRX，and so,how to setup Rx mode in PTX example.   I  use  esb_init()  of example PTX in example PRX， But when I fill data in fifo, it can't trigger NRF_ESB_EVENT_TX_SUCCESS.

[Håkon Alseth]

Hi,

 

Is both PRX and PTX setup with dynamic payload enabled? This is required for the ACK payload feature to be available. (.protocol member in the init function set to "NRF_ESB_PROTOCOL_ESB_DPL")

In order for a PRX device to send a ACK payload, it first has to receive a payload from a PTX device.

Do you get the NRF_ESB_EVENT_RX_RECEIVED event on your PRX device?

 

Kind regards,

Håkon

[wzszzxj]

HI，Alseth:

    Thank you for your replay! In the ESB liberary,how many channels would there be?and what is frequency deviation?

[Håkon Alseth]

Hi!

 

The frequency deviation depends on the mode, but its listed here:

https://infocenter.nordicsemi.com/topic/ps_nrf52840/radio.html?cp=4_0_0_5_19_14_0#unique_168766863

 

In proprietary radio modes you can have one 1MHz spacing between your RF channels (compared to BLE's 2 MHz spacing between RF channels).

 

Kind regards,

Håkon 

[wzszzxj]

Hi,Alseth:

   Thank you!

1.Through  the message, would there be 26 channels all the 2.4GHz bandwidth？

2.when it is transmitting,I catch the waveform by a spectrum analyzer as follow as follow:

from the picture,does it means there is many frequency in one channel bandwidth?Thought，I hold it on that would be one fixed frequency in one  channel.

[Håkon Alseth]

Hi,

wzszzxj said:

1.Through  the message, would there be 26 channels all the 2.4GHz bandwidth？

 ISM band is from 2400 MHz to 2483.5 MHz: https://fccid.io/frequency-explorer.php?lower=2400&upper=2483.5

 

wzszzxj said:

2.when it is transmitting,I catch the waveform by a spectrum analyzer as follow as follow:

from the picture,does it means there is many frequency in one channel bandwidth?Thought，I hold it on that would be one fixed frequency in one  channel.

Which channel are you currently sending on? You will see a bit of noise in the other channels, but this looks more like something is resonating. Can you expand your span so I can see the actual carrier?

 

Kind regards,

Håkon

[wzszzxj]

HI，Alseth:

     That is example esb-ptx.Every channel,every version's SDK----SDK15,SDK16,SDK17,will be like that.and no about spectrum Analyzer's setting,just like follow two waveform picture,it was taken in esb_ptx example,but the source code for simple frequency picture is only  annotating the statement"NRF_RADIO->SHORTS   = m_radio_shorts_common | RADIO_SHORTS_DISABLED_RXEN_Msk;" in document nrf_esb.c,here is the two pictures in the same spectrum analyzer setting(and They are in the same channel 3):

[Håkon Alseth]

Could you enable max hold on the spectrum?

 

Kind regards,

Håkon

[wzszzxj]

Hi，Alseth:

    The two picture is just to make a comparision.Could last picture means that is only a carrier waveform?And the first picture could mean that it is a payload waveform?

[Håkon Alseth]

The first one, with the several smaller spikes, is modulated carrier (ie. a carrier with actual payload data), while the "cleaner" one is a pure sine wave (unmodulated carrier).

 

If you enable max hold on your spectrum analyzer, you should see a more rounded form on the modulated signal as well.

 

Kind regards,

Håkon

[wzszzxj]

Hi,Alseth:

  Thank you for your reply, Pls close this topic,thank you!