Guys,
I was pretty sure I had got it working before, so I didn't want to just
leave it as it is. What I just did is restart my computer with plain FreeDOS
and wrote, compiled and executed a programme like this:
mov ax,0b800h
mov ds,ax
mov word ptr [100h],1f21h ; draw exclamatio
> I'm building a driver (for DOS)
:-) For what hardware ??
> means that the driver will have to do different things to get to the tables
> depending
> on whether HIMEM, or EMM386, or both, or none of them are currently there.
NO. Just use XMS, it is still available even if EMM386 is additionall
>> but then virtual-86 mode is set and I can no loger use 32bit real-mode
>> pointers!
>
> IF you need PM from V86 there is VCPI.
Protected mode isn't the same as flat real mode.
>> Yet, there has to be a way, because HIMEM works even though EMM386 is
>> loaded.
>
> As said, it uses INT $15 /
rking
separatedly. It goes further, but I would need to write a whole document to
explain my exact idea, so I want some code running, before I present it neatly.
What do you reckon?
Lucas
--- On Fri, 30/10/09, Christian Masloch wrote:
From: Christian Masloch
Subject: Re: [Fre
> Is there any site where I can read in very good detail and in a way that
> is easy to understand, how flat-real mode, VCPI and DPMI work and how
> they deal with other previously loaded systems to avoid collisions?
I don't know about such a site. RBIL however provides much information
abou
> > > but then virtual-86 mode is set and I can no loger use 32bit real-mode
> > > pointers!
> > IF you need PM from V86 there is VCPI.
> Protected mode isn't the same as flat real mode.
NO, but there is no absolute need to use flat [un]real mode.
> flat-real mode, VCPI and DPMI work and how the