Here I have a IBM Personal System 2 (PS/2) machine that I've written 16 bit instructions and a CBIOS interrupt call to set video mode all to a floppy diskette. The video mode I'm setting is for graphics mode which does not display a cursor. You will see the initial boot-up all the way to the IBM DOS shell then a power-off, an insertion of the floppy diskette. The first sector (512 bytes and also the coincidentally the boot sector) is loaded with the 16 bit instructions to move the required bits into the required CPU registers, then call CBIOS interrupt 10h. When the floppy diskette with this information is inserted and the computer boots-up, it's first sector is what the CPU executes from memory 0:7C00. Video Here