What is it the advertising duration? Googled, didn't find. What are the rules to set it up?
I guess you are asking about the BLE advertising interval.
Advertising interval is the time gap between two advertising packets send by a BLE advertiser. As per BLE standard in cannot be more than 10.24 seconds. I am not sure about the lower limit, but I think you cannot go below 25ms.
No, I'm asking exactly about advertising duration.
Unfortunately, I don't have main.c source code on my phone but there is a macro defining advertising duration, so I want to know what is it?
#define APP_ADV_DURATION 18000 /**< The advertising duration (180 seconds) in units of 10 milliseconds. */
That's the amount of time the app will advertise before it stops advertising and shuts down. Many of the Nordic demo apps only advertise for 3 minutes and then stop. You can change that to anything you like.
If you'd put that information in the original question it would have helped.
Thanks. I just want to understand ALL the settings, what are they for, how to tune them for my needs. It is unfortunate that SDK documentation doesn't have this OR doesn't point to such description in the "Getting Started" chapter.