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      Debugging &middot; ESP8266 Arduino Core
    
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          ESP8266 Arduino Core
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    <a href="https://github.com/esp8266/Arduino"><div id="gh-icon"></div>esp8266/Arduino</a>
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  <p class="lead">Documentation for ESP8266 Arduino Core. Installation instructions, functions and classes reference.
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      <h2 id="table-of-contents">Table of Contents</h2>

<ul>
<li><a href="#introduction">Introduction</a>

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<li><a href="#Decode">Decode</a></li>
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<h2 id="introduction">Introduction</h2>

<p>If the ESP crash the Exception Cause will be shown and the current stack will be dumped.</p>

<p>example:</p>
<div class="highlight"><pre><code class="language-text" data-lang="text">Exception (0): epc1=0x402103f4 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

ctx: sys 
sp: 3ffffc10 end: 3fffffb0 offset: 01a0

&gt;&gt;&gt;stack&gt;&gt;&gt;
3ffffdb0:  40223e00 3fff6f50 00000010 60000600  
3ffffdc0:  00000001 4021f774 3fffc250 4000050c  
3ffffdd0:  400043d5 00000030 00000016 ffffffff  
3ffffde0:  400044ab 3fffc718 3ffffed0 08000000  
3ffffdf0:  60000200 08000000 00000003 00000000  
3ffffe00:  0000ffff 00000001 04000002 003fd000  
3ffffe10:  3fff7188 000003fd 3fff2564 00000030  
3ffffe20:  40101709 00000008 00000008 00000020  
3ffffe30:  c1948db3 394c5e70 7f2060f2 c6ba0c87  
3ffffe40:  3fff7058 00000001 40238d41 3fff6ff0  
3ffffe50:  3fff6f50 00000010 60000600 00000020  
3ffffe60:  402301a8 3fff7098 3fff7014 40238c77  
3ffffe70:  4022fb6c 40230ebe 3fff1a5b 3fff6f00  
3ffffe80:  3ffffec8 00000010 40231061 3fff0f90  
3ffffe90:  3fff6848 3ffed0c0 60000600 3fff6ae0  
3ffffea0:  3fff0f90 3fff0f90 3fff6848 3fff6d40  
3ffffeb0:  3fff28e8 40101233 d634fe1a fffeffff  
3ffffec0:  00000001 00000000 4022d5d6 3fff6848  
3ffffed0:  00000002 4000410f 3fff2394 3fff6848  
3ffffee0:  3fffc718 40004a3c 000003fd 3fff7188  
3ffffef0:  3fffc718 40101510 00000378 3fff1a5b  
3fffff00:  000003fd 4021d2e7 00000378 000003ff  
3fffff10:  00001000 4021d37d 3fff2564 000003ff  
3fffff20:  000003fd 60000600 003fd000 3fff2564  
3fffff30:  ffffff00 55aa55aa 00000312 0000001c  
3fffff40:  0000001c 0000008a 0000006d 000003ff  
3fffff50:  4021d224 3ffecf90 00000000 3ffed0c0  
3fffff60:  00000001 4021c2e9 00000003 3fff1238  
3fffff70:  4021c071 3ffecf84 3ffecf30 0026a2b0  
3fffff80:  4021c0b6 3fffdab0 00000000 3fffdcb0  
3fffff90:  3ffecf40 3fffdab0 00000000 3fffdcc0  
3fffffa0:  40000f49 40000f49 3fffdab0 40000f49  
&lt;&lt;&lt;stack&lt;&lt;&lt;
</code></pre></div>
<p>the first number after <code>Exception</code> gives the cause of the reset.
a full ist of all causes can be found <a href="../exception_causes.html">here</a>
the hex after are the stack dump.</p>

<h3 id="decode">Decode</h3>

<p>it&#39;s possible to decode the Stack to readable information.
more info see <a href="https://github.com/me-no-dev/EspExceptionDecoder">Esp Exception Decoder</a> tool </p>

<p><img src="ESP_Exception_Decoderp.png" alt="ESP Exception Decoder"></p>

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