IBM ROM BASIC or lack thereof

From: Sean 'Captain Napalm' Conner <spc_at_conman.org>
Date: Wed Oct 3 19:15:41 2001

It was thus said that the Great Tony Duell once stated:
>
> I wish more manufacturers would put a program in the boot ROM that allows
> reading and writing to memory, running (machine code) programs and
> preferably also reading/writing I/O ports (if they're not memory mapped).
> It makes debugging the machine a lot easier if it can't boot a disk (or
> if you don't have a bootable disk for the machine, at least you can do
> something with it.
>
> Tiny (or otherwise) BASIC allows one to do this. So does Forth. Or just a
> little machine code monitor. With ROM space being so cheap these days
> you'd have thought they could find room for something like this...

  Not enough return on investment for that to be done by the BIOS writers or
the PC manufacturers---why waste time on a feature that *may* get used by
less than 1% of 1% of the users?

  On the other hand, why not make an ISA card with your own ROM monitor?
Plug it into a PC, during POST, the BIOS will see the extention ROM and
allow it to hook into the vector table, so you could hook INT 18h on any PC
with this board.

  -spc (I think you have enough equipment to do that, right?)
Received on Wed Oct 03 2001 - 19:15:41 BST