- Boot up the ancient PC XT in your attic, run the ROM dumping tool from DOSLIB2 to dump off a copy of the ROM BIOS and FIXED DISK BIOS on the machine. Remember that you will be transferring it off one 360KB 5.25" floppy at a time... :) - Also use the PC XT to study the various entry points, besides the obvious INT 19h. How is BASICA.COM triggering it, for example? I noticed a straight INT 19h triggers it in a way that "SYSTEM" does not work and you cannot return to DOS. - The Ralph Brown interrupt list vaguely references a whole range of interrupts as related to ROM BASIC. How are they related? Do you call them? Or are they pointers? - Add code to DOSBox-X where, given a BIN image of the PC XT's ROM BIOS, it can boot into ROM BASIC from the DOSBox shell. - How can we work from this towards a native reimplementation of the old ROM BASIC built into DOSBox? - Don't forget runtime warnings such as: "Warning: you're running PC XT ROM BASIC with EGA/VGA output. Please use machine=hercules or machine=cga" to assist the user. - Can we adapt this to work with other variations and versions of ROM BASIC? Can we adapt this code for example so that if DOSBox-X is given ROM BASIC from a Tandy, that it will run it correctly?