ss="keyword">volatile</span> <span class="keyword">static</span> int8_t current_channel = -1; <span class="comment">// volatile because accessed in control and adc ISRs</span></div><div class="line"><a name="l00202"></a><span class="lineno">  202</span>&#160;<span class="keyword">static</span> <span class="keywordtype">bool</span> first = <span class="keyword">true</span>;</div><div class="line"><a name="l00203"></a><span class="lineno">  203</span>&#160;</div><div class="line"><a name="l00204"></a><span cl