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Posted: **Fri Feb 15, 2008 6:27 am**

Hi i implemented multitasking in my baby kernel, in this modes:
SJF, FCFS, RR (round-robin)

Posted: **Sat Feb 16, 2008 12:38 pm**

i have a basic vga, basic ramfs, basic mutlitasking but nothing else so far.

in my old kernel i had working floppy i/o, but im saving that until i get my driver interface working.

Posted: **Thu Feb 28, 2008 5:40 pm**

I'm currently trying to access VGA-Mode, but i can't make it work...

Is it possible to have a look on your sources?

Posted: **Thu Feb 28, 2008 6:09 pm**

Well... my VGA works. I just taken some c code end rewritten it to my asm kernel.

you just have to set a bunch of registers:

Code: Select all

;IN: edi=@register_set
vga.set_registers:
 push eax
 push ecx
 push edx
 push edi
 
;MISC
  mov dx, vga.reg.misc_write
  mov al, [edi]
  out dx, al
  inc edi
  
;sequencer
 xor ecx, ecx
 .loop_seq:
   mov dx,  vga.reg.seq_index
   mov eax, ecx
   out dx,  al
   
   mov dx,  vga.reg.seq_data
   mov al,  [edi]
   out dx,  al
   inc edi
   
   inc ecx
   cmp ecx, 5
 jne .loop_seq

;unlock crtc registers
 mov dx, vga.reg.crtc_index
 mov al, 3
 out dx, al
 
 mov dx, vga.reg.crtc_data
 in  al, dx
 or  al, 0x80   ;set ? bit
 out dx, al
 
 mov dx, vga.reg.crtc_index
 mov al, 11
 out dx, al
 
 mov dx, vga.reg.crtc_data
 in  al, dx
 and al, 0x7F   ;del ? bit
 out dx, al
 
;???make sure they remain unlocked???
 or  byte[edi+ 3],0x80
 and byte[edi+11],0x7F

;write crtc registers
 xor ecx, ecx
 .loop_crtc:
   mov dx,  vga.reg.crtc_index
   mov eax, ecx
   out dx,  al

   mov dx,  vga.reg.crtc_data
   mov al,  [edi]
   out dx,  al
   inc edi

   inc ecx
   cmp ecx, 25
 jne .loop_crtc


;write gc (graphic controller) registers
 xor ecx, ecx
 .loop_gc:
   mov dx,  vga.reg.gc_index
   mov eax, ecx
   out dx,  al

   mov dx,  vga.reg.gc_data
   mov al,  [edi]
   out dx,  al
   inc edi

   inc ecx
   cmp ecx, 9
 jne .loop_gc
 
;write ac (attribute controller) registers
 xor ecx, ecx
 .loop_ac:
   ;?
    mov dx, vga.reg.instat_read
    in  al, dx
   ;?

   mov dx,  vga.reg.ac_index
   mov eax, ecx
   out dx,  al

   mov dx,  vga.reg.ac_data_write
   mov al,  [edi]
   out dx,  al
   inc edi

   inc ecx
   cmp ecx, 21
 jne .loop_ac
 


;/* lock 16-color palette and unblank display */
;	(void)inportb(VGA_INSTAT_READ);
;	outportb(VGA_AC_INDEX, 0x20);

;???lock 16 color palette???
 mov dx, vga.reg.instat_read
 in  al, dx
 mov dx, vga.reg.ac_index
 mov al, 0x20
 out dx, al


 pop edi
 pop edx
 pop ecx
 pop eax
ret

And here are some modes I have in my mode table:

Code: Select all

vga.mode.text_80x25: ;this is the standard mode!
;MISC
 db 0x67
;SEQ
 db 0x03, 0x00, 0x03, 0x00, 0x02
;CRTC
 db 0x5F, 0x4F, 0x50, 0x82, 0x55, 0x81, 0xBF, 0x1F
 db 0x00, 0x4F, 0x0D, 0x0E, 0x00, 0x00, 0x00, 0x50
 db 0x9C, 0x0E, 0x8F, 0x28, 0x1F, 0x96, 0xB9, 0xA3
 db 0xFF
;GC
 db 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x0E, 0x00
 db 0xFF
;AC
 db 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x14, 0x07
 db 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F
 db 0x0C, 0x00, 0x0F, 0x08, 0x00

vga.mode.text_80x50:
;MISC
 db 0x67
;SEQ
 db 0x03, 0x00, 0x03, 0x00, 0x02
;CRTC
 db 0x5F, 0x4F, 0x50, 0x82, 0x55, 0x81, 0xBF, 0x1F
 db 0x00, 0x47, 0x06, 0x07, 0x00, 0x00, 0x01, 0x40
 db 0x9C, 0x8E, 0x8F, 0x28, 0x1F, 0x96, 0xB9, 0xA3
 db 0xFF
;GC
 db 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x0E, 0x00
 db 0xFF
;AC
 db 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x14, 0x07
 db 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F
 db 0x0C, 0x00, 0x0F, 0x08, 0x00

vga.mode.graphic_320x200x256:
;MISC
 db 0x63
;SEQ
 db 0x03, 0x01, 0x0F, 0x00, 0x0E
;CRTC
 db 0x5F, 0x4F, 0x50, 0x82, 0x54, 0x80, 0xBF, 0x1F
 db 0x00, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 db 0x9C, 0x0E, 0x8F, 0x28, 0x40, 0x96, 0xB9, 0xA3
 db 0xFF
;GC
 db 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x05, 0x0F
 db 0xFF
;AC
 db 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07
 db 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F
 db 0x41, 0x00, 0x0F, 0x00, 0x00

vga.mode.graphic_640x480x16:
;MISC
 db 0xE3
;SEQ
 db 0x03, 0x01, 0x08, 0x00, 0x06
;CRTC
 db 0x5F, 0x4F, 0x50, 0x82, 0x54, 0x80, 0x0B, 0x3E
 db 0x00, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 db 0xEA, 0x0C, 0xDF, 0x28, 0x00, 0xE7, 0x04, 0xE3
 db 0xFF
;GC
 db 0x00, 0x00, 0x00, 0x00, 0x03, 0x00, 0x05, 0x0F
 db 0xFF
;AC
 db 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x14, 0x07
 db 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F
 db 0x01, 0x00, 0x0F, 0x00, 0x00

You just have to call it now:

Code: Select all

mov edi, vga.mode.graphic_320x200x256
call vga.set_registers

Posted: **Fri Feb 29, 2008 3:13 am**

Thank you! I'll have a look on it.
But i should have told you that i don't want to use asm where i don't have to. I want to get it work in C or Cpp... So i'm really interested in having a look on lukem's code

Posted: **Sun Mar 02, 2008 5:11 pm**

just look at chris giese's code:

http://my.execpc.com/~geezer/osd/graphics/modes.c

Posted: **Sun Mar 02, 2008 7:45 pm**

lukem_95 wrote:just look at chris giese's code:

http://my.execpc.com/~geezer/osd/graphics/modes.c

Yes, this was the one I "stole" it from. :3

Posted: **Mon Mar 03, 2008 3:14 am**

looks very nice. exactly what i need

but because I've not some functions, i made it

Code: Select all

byte peekb(void *S, short O)
{
	byte *mm = (byte *)S;
	return mm[O];
}

void pokeb(void *S, short O, byte V)
{
	byte *mm = (byte *)S;
	mm[O] = V;
}

void pokew(void *S, short O, word V)
{
	word *mm = (word *)S;
	mm[O] = V;
}

void _vmemwr(void *DS,short DO, const void *S, int N)
{
    const char *sp = (const char *)S;
    char *dpn = (char *)DS;
	char *dp = dpn[DO];
    for(; N != 0; N--) *dp++ = *sp++;
}

but this seems to have problems.

have anyone figure out this functions ?

Posted: **Mon Mar 03, 2008 4:10 am**

in my functions is a problem....
u, guys, how did it get to work in this problem?

Posted: **Mon Mar 03, 2008 4:59 am**

You bumped the thread after waiting less than an hour. Impatience generally doesn't get results - you're on a forum, not everyone is in your timezone, and not everyone is able to answer your question even if they are online.

As for your question, we can't read your mind. What are the specific problems you are having? We can't help you unless we know what the problem is

.

Posted: **Mon Mar 03, 2008 5:25 am**

I get modes.c from the site and i made some changes, because i've not yet implemented some functions. i made some function as i described. the problem is that it get to the video mode but if i want to plot a pixel, there isn't anything on the screen. but for mode 320x200x256 i get something nice

I think there is a problem with my functions(peekb, pokeb, pokew, and _vmemwr)

Code: Select all

byte peekb(void *S, short O)
{
	byte *mm = (byte *)S;
	return mm[O];
}

void pokeb(void *S, short O, byte V)
{
	byte *mm = (byte *)S;
	mm[O] = V;
}

void pokew(void *S, short O, word V)
{
	word *mm = (word *)S;
	mm[O] = V;
}

void _vmemwr(void *DS,short DO, const void *S, int N)
{
    const char *sp = (const char *)S;
    char *dpn = (char *)DS;
	char *dp = dpn[DO];
    for(; N != 0; N--) *dp++ = *sp++;
}

Now works fine, after i used direct memory plotting(VGA_MEM[offset]=color)

Posted: **Mon Mar 03, 2008 8:50 am**

I think somebody plugged 16-bit code directly into 32-bit gcc.

Posted: **Mon Mar 03, 2008 4:57 pm**

this may be what your looking for, but your method works better anyway.

Code: Select all

void _farpokeb(unsigned short selector,
	 unsigned long offset,
	 unsigned char value)
{
  __asm__ __volatile__ ("movw %w0,%%fs\n"
      "	.byte 0x64 \n"
      "	movb %b1,(%k2)"
      :
      : "rm" (selector), "qi" (value), "r" (offset));
}

unsigned char
_farpeekb(unsigned short selector,
	 unsigned long offset)
{
  unsigned char result;
  __asm__ __volatile__ ("movw %w1,%%fs \n"
      "	.byte 0x64 \n"
      "	movb (%k2),%b0"
      : "=q" (result)
      : "rm" (selector), "r" (offset));
  return result;
}

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i gotz VGA =]

multitasking