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PMInfoBlock struc
Signature db 'PMID' ; PM Info Block Signature
EntryPoint dw ? ; Offset of PM entry point within BIOS
PMInitialize dw ? ; Offset of PM initialization entry point
BIOSDataSel dw 0 ; Selector to BIOS data area emulation block
A0000Sel dw A000h ; Selector to access A0000h physical mem
B0000Sel dw B000h ; Selector to access B0000h physical mem
B8000Sel dw B800h ; Selector to access B8000h physical mem
CodeSegSel dw C000h ; Selector to access code segment as data
InProtectMode db 0 ; Set to 1 when in protected mode
Checksum db ? ; Checksum byte for structure
PMInfoBlock ends

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MULTIBOOT_PAGE_ALIGN   equ 1<<0
MULTIBOOT_MEMORY_INFO   equ 1<<1
MULTIBOOT_VIDEO_INFO   equ 1<<2
;MULTIBOOT_AOUT_KLUDGE   equ 1<<16
MULTIBOOT_HEADER_MAGIC   equ 0x1BADB002
MULTIBOOT_HEADER_FLAGS   equ MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_VIDEO_INFO
MULTIBOOT_CHECKSUM   equ -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)

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ALIGN 4
mboot:
   dd MULTIBOOT_HEADER_MAGIC
   dd MULTIBOOT_HEADER_FLAGS
   dd MULTIBOOT_CHECKSUM
; aout kludge. These must be PHYSICAL addresses
   dd mboot
   dd _code
   dd _bss
   dd _end
   dd entry
   dd 0
   dd 800
   dd 600
   dd 32

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    char font_a[]={00111100b,
                        011001100b,
                        11000011b,
                        11000011b,
                        11111111b,
                        11000011b,
                        11000011b};
   int RGBA_white = 0xFFFFFFFF;
   show_character(char *font, char *VRAM, int color, int rowlength) {
       int i, j;
       for (i=0;i<CHAR_HEIGHT;i++,VRAM+=rowlength) {
           char *row=VRAM;
           for (j=1<<CHAR_WIDTH;j!=0;j=j>>1) {
              if (font[i]&j) *row=color;
              row++;
           }
        }
    }

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#define CHAR_HEIGHT 7
#define CHAR_WIDTH 8

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extern unsigned long mboot_info;

char font_a[]=???{0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x78, /* 01111000 */
???0x0c, /* 00001100 */
???0x7c, /* 01111100 */
???0xcc, /* 11001100 */
???0xcc, /* 11001100 */
???0xcc, /* 11001100 */
???0x76, /* 01110110 */
???0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x00, /* 00000000 */
???0x00};
unsigned long  RGBA_black = 0x00000000;
#define CHAR_HEIGHT    16
#define CHAR_WIDTH     8
unsigned long *framebuffer;
SVGAMODEINFO *vbe_mode_info;

void show_character(char *font, unsigned long *VRAM, unsigned long color, int rowlength);

int vbe_init()
{
    multiboot_info_t *mbi;
    union flags_info flags;
    char *image;
    int len = 32*1024, i, j;
    int done = 0;
    image = (char *) kmalloc(len);
    memcpy(image, biosimage, len);
    kprintf("init VBE ... ");
    mbi = (multiboot_info_t *)mboot_info;
    flags.flags = mbi->flags;
    if(flags.bits.bit11 == 1){
???done = 1;
    ???
???vbe_mode_info = (SVGAMODEINFO *)mbi->vbe_mode_info;
???framebuffer = (unsigned long *)vbe_mode_info->physbaseptr;
???if(framebuffer != NULL)
???{
???    int offset = 0;
???    for(j=0; j < 600; j++){
??????for(i=0; i < 800; i++){
??????    offset = 800*j + i;
??????    framebuffer[offset] = RGBA_black;
??????}
???    }
???    show_character(font_a,framebuffer,0xFFFFFFFF, 800);
???}
    }
    return 0;
}

void show_character(char *font, unsigned long *VRAM, unsigned long color, int rowlength) {
      int i, j;
      for (i=0;i<CHAR_HEIGHT;i++,VRAM+=rowlength) {
          unsigned long *row=VRAM;
          for (j=1<<CHAR_WIDTH;j!=0;j=j>>1) {
              if (font[i]&j) *row=color;
              row++;
          }
      }
}

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struct console {
    char width, height;
    int rowstart, currpos;
    char attr;
    short *buffer;

}

/** poor implementation: do not handle lines wider than 
 *  console correctly
 */
putch(struct console *con, char c) {
    if (c=='\n') {
       rowstart+=width;
       currpos=rowstart;
    } else {
        buffer[currpos]=(attr<<8)|c;
        currpos++;
    }
}

long colors[]={
    0x00000000, 0x00004000, 0x00400000, 0x00404000,
    ...
}

/**
 * 
 */
redraw(console*, long *fb) {
  for (int j=0; j<console->height;j++) {
    for (int i=0; i<console->width;i++) {
        if (buffer[j*console->width+i]==0xFFFF) continue;
        clear_character(fb,colors[buffer[...]>>12],i,j);
        draw_character(fb,(colors[buffer[...]>>8)&0x0f, font[buffer[...]&0xff]);
        buffer[...]=0xffff;
    }
  }
}