Speed up scanning of advertising time

[TimLin]

I use pc-ble-driver to control nRF52840 dongle.
I want to speed up scanning of advertising time.

So I change SCAN_INTERVAL and SCAN_WINDOW.

How can I modify the parameters anyway.

The scanning speed is not less than 30ms.

[Simonr]

Hi

What do you mean by scanning speed? Is this the time between each scanning window or what?

To edit the scan interval it should be sufficient to use the SCAN_WINDOW and SCAN_INTERVAL variables. The central will scan for SCAN_WINDOW time, every SCAN_INTERVAL interval. These parameters are generally given in units of 0.625ms. So if you set SCAN_INTERVAL = SCAN_WINDOW, you should scan 100% of the time.

Best regards,

Simon

[TimLin]

Scanning speed 30ms means receiving the advertising events every 30ms.

I set SCAN_INTERVAL 20ms, but I still receive the advertising events every 30ms.

[Simonr]

Hi

Okay, what is the advertising interval in the peripheral you're scanning for, as it will also depend on how often that device advertise, In BLE, the time between advertisement packets is the advertising interval + a random delay of 0-10 ms (as defined by the BLE specification). 

Can you also provide some information as to how you measure the time between received advertising events.

Best regards,

Simon

[TimLin]

Hi Simon,

I use GetSystemTime function to record the computer time of each event.

But Now,I change the api version (nrf-ble-driver-sd_api_v5-mt-4_1_4.dll).

The old version I used is 4_1_2.

It can receive faster. I measure the time is 15ms.

Thanks you for your reply.

Best regards,

Tim