Re: [OpenBIOS] asm code

[Edwin Rhodes]

what code do i need to zero 0b8000 - 0bfff0.
thanks edwin
----- Original Message -----
From: James 
To: 
Sent: Monday, February 21, 2000 3:27 PM
Subject: Re: [OpenBIOS] asm code
> > hi sorry this is slightly off topic but i need some asm code to clear
> > the screen in the linux kernel -- just after it says uncompressing
> > linux. how would i implement this in assembler, that would compile
> > under gas. thanks edwin
>
> By the time it says "uncompressing linux" it is already in 32 bit mode C
> code (inflate.c).  It is writing to the screen directly at memory address
> 0b8000.  To clear the screen, just zero 0b8000 - 0bfff0.
> > ps. will you eventually implement all the standard bios calls so that
> > other os's such as dos etc will run under open bios? or will it be
> > just a bios for linux?  thanks and good luck.
>
> I believe the goal is to get support for the 32 bit OSs that don't use the
> BIOS, like WinNT, BeOS, Linux, BSD, and others (at least I think that is
> the goal and I think those OSs don't use the BIOS).
>
> James
>
> To unsubscribe: send mail to [e-mail]
> with 'unsubscribe openbios' in the body of the message

-
To unsubscribe: send mail to [e-mail]
with 'unsubscribe openbios' in the body of the message

asm code

[James]

/*
Since you are already in C after it uncompresses the kernel, you could
do something like:
*/

int i;
  void *vidmem = 0x0b8000;

for (i = 0; i < 80*25*2; i++) {     /*  Clear an 80*25 screen  */
    *(vidmem + i) = 0;
  }

/*
  Something like that, at least; I've been doing way too much Java
recently, I can't think straight..
  The harder part is writing something to the screen; letters are on the
even bytes (0xb8000, 0xb8002, 0xb8004, etc), attributes are on the odd
ones (0xb001, 0xb003...).
    - James
> what code do i need to zero 0b8000 - 0bfff0.
> thanks edwin
> ----- Original Message -----
> From: James 
> To: 
> Sent: Monday, February 21, 2000 3:27 PM
> Subject: Re: [OpenBIOS] asm code
> > > hi sorry this is slightly off topic but i need some asm code to clear
> > > the screen in the linux kernel -- just after it says uncompressing
> > > linux. how would i implement this in assembler, that would compile
> > > under gas. thanks edwin
> >
> > By the time it says "uncompressing linux" it is already in 32 bit mode C
> > code (inflate.c).  It is writing to the screen directly at memory address
> > 0b8000.  To clear the screen, just zero 0b8000 - 0bfff0.
> > > ps. will you eventually implement all the standard bios calls so that
> > > other os's such as dos etc will run under open bios? or will it be
> > > just a bios for linux?  thanks and good luck.
> >
> > I believe the goal is to get support for the 32 bit OSs that don't use the
> > BIOS, like WinNT, BeOS, Linux, BSD, and others (at least I think that is
> > the goal and I think those OSs don't use the BIOS).
> >
> > James
> >
> > To unsubscribe: send mail to [e-mail]
> > with 'unsubscribe openbios' in the body of the message
>
> To unsubscribe: send mail to [e-mail]
> with 'unsubscribe openbios' in the body of the message

-
To unsubscribe: send mail to [e-mail]
with 'unsubscribe openbios' in the body of the message

asm code

[Ronald G. Minnich]

On Wed, 1 Mar 2000, Edwin Rhodes wrote:
> what code do i need to zero 0b8000 - 0bfff0.
> thanks edwin

there's a nice memset in the main.c part of openbios.

ron

-
To unsubscribe: send mail to [e-mail]
with 'unsubscribe openbios' in the body of the message