2024-04-25 20:44:23 -07:00

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- 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?