Hi,
i was wondering how to increase the sampling frequency to 16 MHz instead of the standard 8 MHz. I tried to play around with the #define CWD_S_RATE_M_DEFAULT in cw_distance.h, but when changing the value the DTE doesnt seem to take place anymore. The Initiator and Responder just connect, but they dont carry out the DTE. Here is the output from the Initiators-perspective:
exchange_mem_params_exchange: role: 1, host_ready: 1, fstep: 2, nb_atoms: 40
initialized cw distance calculation with nb_atoms=40 and 5120 samples
xtal trim 0x120
Ble central DTE task
Device address: D2:33:A7:D3:E9:4C
Device address type: 1
Peripheral device found: set_nb: 0 (C2:DF:B5:0A:22:B0)
handle_evt_gap_scan_completed: status=000c
Connecting...(C2:DF:B5:0A:22:B0)
handle_evt_gap_connected: conn_idx=0000
Exchanging MTU
Connection completed with status 0
MTU set to 512 bytes
And then there's nothing. No range beeing displayed on the LCDs or in the console. Can somebody help me understand why this is happening?
David
Config: SmartSnippets Studio V2.0.16.1760, SDK: WiRa_19.440.8.6, Development Kit-USB: DA14695
Hi David,
Thanks for your question. Please let me check it and I'll get back to you.
Thanks, PM_Dialog
Hi David ,
According to the Team internally, it is not possible to increase the sampling frequency from 8MHz to 16Mhz for DTE.
The command for setting DTE parameters is ble_gap_dte_params_set and there is no parameter for sampling frequency.
The #define CWD_S_RATE_M_DEFAULT is used in the distance calculations. It should not change since the library expects the 8MHz rate. The change will affect the expected number of samples from DTE and if the iq data samples do not match the expected number of samples an assertion will trigger in cwd_set_buffer.
Thanks, PM_Dialog
Thanks for the clarification with the #define CWD_S_RATE_M_DEFAULT !
In the User Manual "SmartBond™ Wireless Ranging SDK - UM-B-137", under Section 5.2 "Dialog Tone Exchange" is stated, that the data from the RFMON contains "9-bit RF-ADC samples (IQ data) that are sampled at an 8 MHz sampling frequency (16 MHz sampling frequency is also possible with DA1469x)".
So i thought, there had to be a define statement to increase the sampling frequency, to bring it up to 16 MHz. If there isn't, what is this sentence in the manual suppose to mean? Can you change the sampling rate in a different way?
Hi David,
Thanks for pointing this out. I have escalated this internally to check it.
Thanks, PM_Dialog