I've been puzzling about the very long lag time I'm seeing. Due to advertising interval, scan interval and scan window with an advertising interval of 20ms, I'm just not understanding how or why I'm seeing seconds between when the advertisor/beacon starts sending the data to when the observer receives it.
SInce we can set the advertising window (20ms in my case) the other piece of the puzzle is on the observer side. It seems the two most important things are scan interval and the scan window.
As I understand things, the scan interval is how often the scan process starts. The interval is how long presumable the radio is on and actually listening.
If the scan interval is say 100ms and the scan window is 20ms, that means every 100ms the radio is turned on and listening for 20ms then radio turned off for 80ms and the whole thing starts again.
So I guess the first question is are the value's being used for scan interval and window? Can we change them? My observer is running on wall power so it's power useage is a non-issue. On the beacon side we can & will play some games to help reduce power usage.
But before I can play those games, I need to know where the bottle necks are and why it is taking so long for the observer to respond. Measured in seconds.
PS: My main source of info is "Getting Started with BLE by Kevin Townsend, Carles Cufi & Akiba Davidson. Part of what I call the O'Reily "warm fuzzy animal" series.