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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>nRF52832 debug</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/28721/nrf52832-debug</link><description>Hi,
I have a similar requirement as stated in this question. 
 I am using nrf52832_xxaa with SDK v11.0. I have the following queries 
 a. Can external debugger modify CTRL-AP - Control Access Port? 
 b. What happens when I reset my hardware over JLink</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Thu, 21 Dec 2017 07:25:09 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/28721/nrf52832-debug" /><item><title>RE: nRF52832 debug</title><link>https://devzone.nordicsemi.com/thread/113831?ContentTypeID=1</link><pubDate>Thu, 21 Dec 2017 07:25:09 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:6ce5ba52-89ad-4375-ba82-d944a9248cb8</guid><dc:creator>endnode</dc:creator><description>&lt;p&gt;The question you link is answered and valid for both nRF51 and nRF52 (see registers&amp;#39; description in their respective specifications). Now to your three additional questions (which are not so much related to the first one in fact;):&lt;/p&gt;
&lt;p&gt;a) Yes external debugger can access CTRL-AP.&lt;/p&gt;
&lt;p&gt;b) From functional point of view it&amp;#39;s equal to any other reset mean (e.g. the method you list in point c). If you are interested into very technical details what is sent over SWD (it shouldn&amp;#39;t be PIN reset which is different &lt;code&gt;nrfjprog -p&lt;/code&gt; command) then &lt;a href="https://mcuoneclipse.com/2016/01/17/hardware-reset-for-arm-cortex-m-with-segger-j-link-and-kinetis-design-studio/"&gt;this article&lt;/a&gt; might give you way how to find it.&lt;/p&gt;
&lt;p&gt;c) If you use &lt;code&gt;NVIC_SystemReset()&lt;/code&gt; function in your code then (as you can see CMSIS file corresponding to use ARM Cortex architecture) specific value is written to &lt;code&gt;SCB-&amp;gt;AIRCR&lt;/code&gt; register and then busyloop waits until core resets itself. See e.g. &lt;code&gt;components\toolchain\cmsis\include\core_cm4.h&lt;/code&gt; nRF5 SDk file.&lt;/p&gt;
&lt;p&gt;Back to your original line: if you want to disable debugging interface (and actually protect the chip against read-back of ROM and RAM and other memory regions during run-time) then you follow the answer there. If you just play with the debugger and you are interested in particular actions there are hopefully some answers here.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>