IBM ROM BASIC or lack thereof

From: Derek Peschel <dpeschel_at_eskimo.com>
Date: Tue Oct 2 01:40:25 2001

On Tue, Oct 02, 2001 at 01:00:45AM -0400, Glen Goodwin wrote:
> Tony Duell wrote:
>
> > Since they never did provide BASIC they had to make INT 18 do something
> > (remember an application program could, in theory, call that interrupt).
> > Since that interrupt should have entered ROM BASIC, the most sensible
> > thing to do was to print that there was no ROM BASIC and then halt the
> > CPU.
>
> Since "they never did provide BASIC" then there was *always* "no ROM
> BASIC." That's like stopping the machine with a message stating "no
> printer." Why not display something understandable to a common user, such
> as "no bootable device?"

Of course that makes much more sense. Someone (I think Iggy) pointed out
that that's exactly what modern BIOSes do.

I wonder if any code tries to call INT 18h after the system was running?
(I hope that's not the way BASICA works.) If you did, a message saying "No
ROM BASIC" would be much clearer than one saying "No bootable device". But
I'm sure most of the time INT 18h got called at boot time, so I would still
vote for a "No bootable device" message.

-- Derek
Received on Tue Oct 02 2001 - 01:40:25 BST