X86 on Institute of Ineptitudehttps://ineptitude.ca/tags/x86/Recent content in X86 on Institute of IneptitudeHugo -- 0.153.1enTue, 11 Nov 2025 14:57:43 -0700Assemble an MS-DOS .COM binary with DEBUG.EXEhttps://ineptitude.ca/writing/assemble-dos-com/Tue, 11 Nov 2025 14:57:43 -0700https://ineptitude.ca/writing/assemble-dos-com/<p><a href="https://www.youtube.com/The8BitGuy">The 8-Bit Guy</a> has a video where he <a href="https://www.youtube.com/watch?v=HWpi9n2H3kE">demonstrates the assembler built right into the monitor ROM on a C64</a>.</p> <p>This fascinated me and made me wonder&hellip; If I was stuck on an old MS-DOS machine and wanted to assemble a binary&hellip; Could I do it? Byte by byte? With what tool? Those of us stuck with &ldquo;IBM compatible&rdquo; PCs didn&rsquo;t have no fancy monitor ROMs.</p> <p>Turns out MS-DOS&rsquo; <code>DEBUG.EXE</code> is and was entirely up for the job.</p>