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<a href='https://github.com/akkartik/mu/blob/main/baremetal/ex2.subx'>https://github.com/akkartik/mu/blob/main/baremetal/ex2.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Test out the video mode by filling in the screen with pixels.</span>
<span id="L2" class="LineNr"> 2 </span><span class="subxComment">#</span>
<span id="L3" class="LineNr"> 3 </span><span class="subxComment"># To build a disk image:</span>
<span id="L4" class="LineNr"> 4 </span><span class="subxComment">#   ./translate_subx_baremetal baremetal/ex2.subx    # emits disk.img</span>
<span id="L5" class="LineNr"> 5 </span><span class="subxComment"># To run:</span>
<span id="L6" class="LineNr"> 6 </span><span class="subxComment">#   qemu-system-i386 disk.img</span>
<span id="L7" class="LineNr"> 7 </span><span class="subxComment"># Or:</span>
<span id="L8" class="LineNr"> 8 </span><span class="subxComment">#   bochs -f baremetal/boot.bochsrc  # boot.bochsrc loads disk.img</span>
<span id="L9" class="LineNr"> 9 </span><span class="subxComment">#</span>
<span id="L10" class="LineNr">10 </span><span class="subxComment"># Expected output:</span>
<span id="L11" class="LineNr">11 </span><span class="subxComment">#   html/baremetal.png</span>
<span id="L12" class="LineNr">12 </span>
<span id="L13" class="LineNr">13 </span>== code
<span id="L14" class="LineNr">14 </span>
<span id="L15" class="LineNr">15 </span><span class="subxFunction">main</span>:
<span id="L16" class="LineNr">16 </span>  <span class="subxComment"># ecx &lt;- start of video memory</span>
<span id="L17" class="LineNr">17 </span>  8b/-&gt; *0x7f28 1/r32/ecx
<span id="L18" class="LineNr">18 </span>
<span id="L19" class="LineNr">19 </span>  <span class="subxComment"># eax &lt;- final pixel of video memory</span>
<span id="L20" class="LineNr">20 </span>  8d/copy-address *(ecx + 0x0bffff) 0/r32/eax  <span class="subxComment"># 0xbffff = 1024*768 - 1</span>
<span id="L21" class="LineNr">21 </span>
<span id="L22" class="LineNr">22 </span>  <span class="subxComment"># for each pixel in video memory</span>
<span id="L23" class="LineNr">23 </span>  {
<span id="L24" class="LineNr">24 </span>    39/compare %eax 1/r32/ecx
<span id="L25" class="LineNr">25 </span>    7c/jump-if-&lt; <span class="Constant">break</span>/disp8
<span id="L26" class="LineNr">26 </span>    <span class="subxComment"># write its column number to it</span>
<span id="L27" class="LineNr">27 </span>    88/byte&lt;- *eax 0/r32/AL
<span id="L28" class="LineNr">28 </span>    48/decrement-eax
<span id="L29" class="LineNr">29 </span>    eb/jump <span class="Constant">loop</span>/disp8
<span id="L30" class="LineNr">30 </span>  }
<span id="L31" class="LineNr">31 </span>
<span id="L32" class="LineNr">32 </span>  <span class="subxComment"># hang indefinitely</span>
<span id="L33" class="LineNr">33 </span>  {
<span id="L34" class="LineNr">34 </span>    eb/jump <span class="Constant">loop</span>/disp8
<span id="L35" class="LineNr">35 </span>  }
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