video RAM (0b800h)

why can't I write on the video RAM (0b800h) using assembly programs,it works
on XP but it doesn't work on vista

M.El Nahas <> wrote:

>why can't I write on the video RAM (0b800h) using assembly programs,it works
>on XP but it doesn't work on vista

That's a DOS trick, I think. I can't imagine that it worked on XP.
Maybe in Win95 compatibility mode?

In general, any program that tries to access hardware directly - which
is exactly what you're doing - will not work in XP or Vista. Also--DOS
mapped video memory to that location, but not XP or Vista.

--
Tim Slattery
MS MVP(Shell/User)

http://members.cox.net/slatteryt

Hi, Tim.

Yeah, that's how we used to do it on the TRS-80! ;^}

I was shocked - happily! - the first time I saw how quickly the screen could
turn white with a Poke command, compared to Print, in BASIC!

RC
--
R. C. White, CPA
San Marcos, TX

Microsoft Windows MVP
(Running Windows Live Mail 2008 in Vista Ultimate x64)

"Tim Slattery" <> wrote in message
news:...
> M.El Nahas <> wrote:
>
>>why can't I write on the video RAM (0b800h) using assembly programs,it
>>works
>>on XP but it doesn't work on vista
>
> That's a DOS trick, I think. I can't imagine that it worked on XP.
> Maybe in Win95 compatibility mode?
>
> In general, any program that tries to access hardware directly - which
> is exactly what you're doing - will not work in XP or Vista. Also--DOS
> mapped video memory to that location, but not XP or Vista.
>
> --
> Tim Slattery
> MS MVP(Shell/User)
>
> http://members.cox.net/slatteryt