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<?xml-stylesheet type="text/xsl" href="https://devzone.nordicsemi.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>S140 6.0.0 SCANNING ISSUE</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/34630/s140-6-0-0-scanning-issue</link><description>Hi All! 
 Faced with big problem with SCANNING procedure (nRF52840) 
 We have a BLE network : one CENTRAL and up to 6 PERIPHERALs can be connected simultaneously to the CENTRAL. 
 Advertising period of Peritherals is 1 second. 
 THE PROBLEM: 
 if no connected</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Wed, 30 May 2018 07:53:19 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/34630/s140-6-0-0-scanning-issue" /><item><title>RE: S140 6.0.0 SCANNING ISSUE</title><link>https://devzone.nordicsemi.com/thread/133958?ContentTypeID=1</link><pubDate>Wed, 30 May 2018 07:53:19 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:e8513a79-1ecc-4627-9ff1-65d576386255</guid><dc:creator>Edvin</dc:creator><description>&lt;p&gt;Hello,&lt;/p&gt;
&lt;p&gt;Please see Section 15.4 in the &lt;a href="http://infocenter.nordicsemi.com/pdf/S132_SDS_v6.0.pdf"&gt;S140 v6 SoftDevice Specification&lt;/a&gt;.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Also note that there have been some issues with a too long scanning interval. Set it below 16.7 seconds to be sure.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;But as you see in section 15.4 (Scheduling -&amp;gt; scanner timing), if you set the scan window longer than:&lt;/p&gt;
&lt;p&gt;Scan&amp;nbsp;window = connection interval - ( Σt_[connection event] + t_[scan_reserved]) you may loose a connection event, resulting in a lost connection unless you have slave latency.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;You can try to increase your advertising interval to increase the chance of detecting an advertisement. This will cost a bit more power while advertising, but that is a cost of&amp;nbsp;increasing the chance&amp;nbsp;to be detected sooner.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Advertising and scanning is not a way of communication that is guaranteed to be detected at once, since the communication is not synchronized. See the advertising and scanning timing scheduling in the SoftDevice Specification.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Best regards,&lt;/p&gt;
&lt;p&gt;Edvin&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: S140 6.0.0 SCANNING ISSUE</title><link>https://devzone.nordicsemi.com/thread/133644?ContentTypeID=1</link><pubDate>Mon, 28 May 2018 12:11:49 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:e97f7439-b743-4af0-a3bb-c3545bda97ff</guid><dc:creator>Edvin</dc:creator><description>&lt;p&gt;Hello,&lt;/p&gt;
&lt;p&gt;Sorry for the late reply. I just wanted to let you know that I have to check what the softdevice does with the scanning when it is in a connection, and gets a connection event within the scan interval. I am not sure whether it resumes the scanning afterwards, or if it waits for the next scan interval to resume the scanning.&lt;/p&gt;
&lt;p&gt;I will come back to you as soon as I know anything.&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;BR,&lt;/p&gt;
&lt;p&gt;Edvin&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: S140 6.0.0 SCANNING ISSUE</title><link>https://devzone.nordicsemi.com/thread/133105?ContentTypeID=1</link><pubDate>Wed, 23 May 2018 19:58:26 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:239379be-6e31-4bce-9fac-5c82f4a1ea45</guid><dc:creator>Aylik</dc:creator><description>&lt;p&gt;Hi Edvin,&lt;/p&gt;
&lt;p&gt;I tested &amp;gt; 100&amp;nbsp; variants, in my case, stable result only with use;&lt;/p&gt;
&lt;p&gt;.interval = 3200 ,&amp;nbsp;.window&amp;nbsp; = 2615&lt;/p&gt;
&lt;p&gt;all other cases work very unstable (10/10, 20/20, 0xfff/0xfff, 3200/3200, 3200/2000, etc ....)&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Please, exlain how it does work.&lt;/p&gt;
&lt;p&gt;.. also, I find after ~ 2 minutes , Scanning again becomes unstable until RESET...&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: S140 6.0.0 SCANNING ISSUE</title><link>https://devzone.nordicsemi.com/thread/133017?ContentTypeID=1</link><pubDate>Wed, 23 May 2018 13:11:29 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:9cacbb68-bc4e-40e9-b16e-5f92815fcfdc</guid><dc:creator>Edvin</dc:creator><description>&lt;p&gt;Hello,&lt;/p&gt;
&lt;p&gt;Having a short scanning interval means that the softdevice has to change channel more often. Can you please try to increase the scanning interval a bit. Just for testing, try to set both the .interval and .window to something like 0x0FFF.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;BR,&lt;/p&gt;
&lt;p&gt;Edvin&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>