My DOS Corner

I am a big fan of 86-DOS, the operating system which was sold to Microsoft to become MS-DOS.

Below are some of my DOS works, done with my friend Rich Cini and others:

86-DOS 0.11 source code - reconstructed source code of 86-DOS 0.11, the earliest version of DOS
Paterson's DOS listings - printer listings containing DOS source code, from Tim Paterson
86-DOS on IBM PC - every version of 86-DOS ported to run on the IBM PC
SCP 8086 Monitor - the monitor ROM for booting 86-DOS
MicroPro WordMaster - the text editor Tim Paterson used to write DOS
PC-DOS 1.00 BIOS & boot sector - my journey disassembling the PC-DOS 1.00 BIOS and boot sector

Page written by Yufeng Gao. Last updated: 2026/04/28.