timer event stops advertising

RE: timer event stops advertising

samet kocatepe — Tue, 22 Dec 2015 10:30:00 GMT

hi martin,

i have tested the firmware about 4 days. it seems it is ok. thanks .

RE: timer event stops advertising

samet kocatepe — Wed, 16 Dec 2015 12:37:32 GMT

Hi Martin, I was on a trip so sorry for late reply, and also thank you and all nordic team for being helpful.

Martin, At the MCP side you already know that user can not change advertising interval and window. but in my bluegiga script i can sert interval and window which i want. Right now , my scan window and scan interval are both set to $30 (which is 0x30 and 0x30=48D --> 48*0.625=30 ms ). you see advertisement interval and window are equal and short. at the nordic side i used all off three advertisement channels (37, 38 and 39) and there is not any reason to frustrate for scanner side.

Anyway, today i set a GSM telemetry logger device with bluegiga scanner, tommorrow i will notice you about results. my best regards. Samet.

RE: timer event stops advertising

MartinBL — Thu, 10 Dec 2015 14:40:50 GMT

Hi,

I think I have the answer to your question regarding the pauses in the advertising. The problem is not the timers, but the interval at which you are advertising. In your code you have the following line:

#define NON_CONNECTABLE_ADV_INTERVAL    MSEC_TO_UNITS(500, UNIT_0_625_MS)

meaning, as I'm sure you know, that you are advertising every 500 ms. This is a relatively long interval and your scanners (your bluegiga and MCP) needs to take this into account if you want to capture every advertising packet. So I tried your code and I too saw what seemed to be a regular pause in the advertising using MCP, so I pulled out my sniffer from my drawer and was able to produce this graph:

As you can see, even though it might not seem so in MCP the device is actually advertising every 500 ms all the time. So the issue is actually on your scanner side. Have a look at this image:

Your scan intervals are probably too long and your scan window lengths are too short and this makes it hard for you scanner to "hit" the advertising packets. That is why you see the pauses. You get these regular pauses because for a certain amount of time the scan windows overlap with the advertising interval, but over time the window will drift in time compared to the advertising packet until the windows are not hitting the advertising packets at all. Then a couple of seconds later the windows have drifted even further and overlap the advertising packets again. So I adjusted the scan window and interval to 510 ms and 511 ms respectively in MCP (hit "File -> Options -> Scanning"). This means that MCP scans for 510 ms, stops for 1 ms, scans for 510, and so on, making it very likely to hit every advertising packet. Now I could see the device advertising regularly all the time.

RE: timer event stops advertising

samet kocatepe — Wed, 09 Dec 2015 10:42:20 GMT

in two ways, one is my bluegiga ble module (espesially for this beacon) , it scans and reports to me via serial port and i log it using terminal.exe .Terminal.exe is a com port listener and shows time and also can log. another way is nrf master control panel android app. when beacon stops advertising, bluegiga modul and nRF MCP app can not find any devices simutanously. and after some times it continues to advertsing .

RE: timer event stops advertising

MartinBL — Wed, 09 Dec 2015 09:49:24 GMT

Hi, I thought I should let you know that I'm still looking into this. May I ask what methods you use to observe that the softdevice stops advertising?

RE: timer event stops advertising

samet kocatepe — Mon, 07 Dec 2015 10:24:54 GMT

hi martin i updated my question and attached main.c file. thanks in advance.

RE: timer event stops advertising

MartinBL — Thu, 03 Dec 2015 13:32:14 GMT

Hi, Can you please upload your main.c file? If you are not comfortable doing it here in public you can submit it on our official support portal for confidentiality.