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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>connection request to a known address</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/23688/connection-request-to-a-known-address</link><description>Hi guys,
I want to ask if it is possible for a nrf51822 to connect to a Central ( my cell phone) without advertising. Let assume that my cell phone has nrf51822&amp;#39;s MAC address from the first connection and it can send a connection request to nrf51822</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Wed, 26 Jul 2017 15:14:09 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/23688/connection-request-to-a-known-address" /><item><title>RE: connection request to a known address</title><link>https://devzone.nordicsemi.com/thread/93113?ContentTypeID=1</link><pubDate>Wed, 26 Jul 2017 15:14:09 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:17fac0b0-6045-457e-ab48-162350ee0c37</guid><dc:creator>J&amp;#248;rgen Holmefjord</dc:creator><description>&lt;p&gt;From &lt;a href="https://devzone.nordicsemi.com/blogs/782/bluetooth-smart-and-the-nordics-softdevices-part-1/"&gt;this blog post&lt;/a&gt;:&lt;/p&gt;
&lt;blockquote&gt;
&lt;p&gt;&lt;strong&gt;ADV_DIRECT_IND: connectable directed advertising&lt;/strong&gt;&lt;/p&gt;
&lt;/blockquote&gt;
&lt;blockquote&gt;
&lt;p&gt;You use this to
direct your advertise packet to one
specific central to ask for
connection. The packet is still a
broadcast packet but other scanners
will ignore the packet if the peer
address is not matched with them. And
connect request or scan request from
unmatched central will be ignored by
the advertiser. Directed advertising
usually comes with high duty cycle
with interval fix at 3.75ms. For low
duty cycle directed advertising, it&amp;#39;s
configurable and should be &amp;lt;10ms.
(Section 4.4.2 Part B Vol 6).&lt;/p&gt;
&lt;/blockquote&gt;
&lt;p&gt;The advertising method is the same. The current consumption will depend on the advertising interval, and scan interval settings of the central. More current might be used before connection, but connection might be initiated sooner, lowering the total average current consumption.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: connection request to a known address</title><link>https://devzone.nordicsemi.com/thread/93114?ContentTypeID=1</link><pubDate>Wed, 26 Jul 2017 02:43:43 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:9b920545-1711-4695-beb9-f01c4be86cb3</guid><dc:creator>Hust</dc:creator><description>&lt;p&gt;Thank you very much for your reply, btw, how about the power? Is advertising to only one central requires less power than undirect advertising?&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: connection request to a known address</title><link>https://devzone.nordicsemi.com/thread/93112?ContentTypeID=1</link><pubDate>Sat, 22 Jul 2017 05:01:18 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:204340b6-ad65-4a0b-94ea-8d9b9f9913bf</guid><dc:creator>RK</dc:creator><description>&lt;p&gt;No it&amp;#39;s not. The Bluetooth protocol requires that a device be advertising before it&amp;#39;s connectable. You can advertise yourself as connectable to only one central, but you need to advertise.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>