<spanclass="line"><span>*** DFU device disconnected: Atmel Corp: ATmega32U4 (03EB:2FF4:0000)</span></span></code></pre></div><h2id="flash-your-keyboard-from-the-command-line"tabindex="-1">Flash your Keyboard from the Command Line <aclass="header-anchor"href="#flash-your-keyboard-from-the-command-line"aria-label="Permalink to "Flash your Keyboard from the Command Line""></a></h2><p>This has been made pretty simple compared to what it used to be. When you are ready to compile and flash your firmware, open up your terminal window and run the flash command:</p><divclass="language-sh vp-adaptive-theme"><buttontitle="Copy Code"class="copy"></button><spanclass="lang">sh</span><preclass="shiki shiki-themes github-light github-dark vp-code"><code><spanclass="line"><spanstyle="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">qmk</span><spanstyle="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> flash</span></span></code></pre></div><p>If you did not configure your keyboard/keymap name in the CLI according to the <ahref="./newbs_getting_started">Configure your build environment</a> section, or you have multiple keyboards, you can specify the keyboard and keymap:</p><divclass="language-sh vp-adaptive-theme"><buttontitle="Copy Code"class="copy"></button><spanclass="lang">sh</span><preclass="shiki shiki-themes github-light github-dark vp-code"><code><spanclass="line"><spanstyle="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">qmk</span><spanstyle="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> flash</span><spanstyle="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> -kb</span><spanstyle="--shiki-light:#D73A49;--shiki-dark:#F97583;"><</span><spanstyle="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">my_keyboar</span><spanstyle="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">d</span><spanstyle="--shiki-light:#D73A49;--shiki-dark:#F97583;">></span><spanstyle="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> -km</span><spanstyle="--shiki-light:#D73A49;--shiki-dark:#F97583;"><</span><spanstyle="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">my_keyma</span><spanstyle="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">p</span><spanstyle="--shiki-light:#D73A49;--shiki-dark:#F97583;">></span></span></code></pre></div><p>This will check the keyboard's configuration, and then attempt to flash it based on the specified bootloader. This means that you don't need to know which bootloader that your keyboard uses. Just run the command, and let the command do the heavy lifting.</p><p>However, this does rely on the bootloader being set by the keyboard. If this information is not configured, or you're using a board that doesn't have a supported target to flash it, you will see this error:</p><divclass="language- vp-adaptive-theme"><buttontitle="Copy Code"class="copy"></button><spanclass="lang"></span><preclass="shiki shiki-themes github-light github-dark vp-code"><code><spanclass="line"><span>WARNING: This board's bootloader is not specified or is not supported by the ":flash" target at this time.</span></span></code></pre></div><p>In this case, you'll have to fall back on specifying the bootloader. See the <ahref="./flashing">Flashing Firmware</a> Guide for more details.</p><divclass="warning custom-block"><pclass="custom-block-title">WARNING</p><p>If your bootloader is not detected by <code>qmk flash</code>, try running <code>qmk doctor</code> for suggestions on how to fix common problems.</p></div><h2id="test-it-out"tabindex="-1">Test It Out! <aclass="header-anchor"href="#test-it-out"aria-label="Permalink to "Test It Out!""></a></h2><p>Congrats! Your custom firmware has been programmed to your keyboard and you're ready to test it out!</p><p>With a little bit of luck everything will work perfectly, but if not there are steps that will help you figure out what's wrong. Testing your keyboard is usually pretty straightforward. Press every single key and make sure it sends the keys you expect. You can use <ahref="https://config.qmk.fm/#/test/"target="_bla
