https://mjgraf.net/tags/avr/ Recent content in AVR on mjgraf.net Hugo en-gb Michael J. Graf Mon, 23 Jul 2018 00:00:00 +0000 https://mjgraf.net/electronics/1807-avr-data-memory-usage/ Mon, 23 Jul 2018 00:00:00 +0000 https://mjgraf.net/electronics/1807-avr-data-memory-usage/ <p>&hellip; is that on the AVR, <strong>the &ldquo;Data Memory Usage&rdquo; information given by AVRGCC only refers to memory allocated at compile time, and does not take the stack into account.</strong><sup id="fnref:1"><a href="#fn:1" class="footnote-ref" role="doc-noteref">1</a></sup><sup id="fnref:2"><a href="#fn:2" class="footnote-ref" role="doc-noteref">2</a></sup> The stack is not to be underestimated: it holds not only the return addresses from function calls, but also <em>all local variables</em><sup id="fnref:3"><a href="#fn:3" class="footnote-ref" role="doc-noteref">3</a></sup> of the function(s) called.</p> <p>So you might feel safe and sound reading something like &ldquo;Data Memory Usage : 66 bytes 51,6% Full&rdquo;, thinking there&rsquo;s plenty of space left for future features; and then the stack still swoops down and corrupts your precious data because of a couple of nested function calls.</p>