gistfile1.txt

#define VBE_DISPI_IOPORT_INDEX 0x01CE
#define VBE_DISPI_IOPORT_DATA  0x01CF
#define VBE_DISPI_INDEX_ID              0x0
#define VBE_DISPI_INDEX_XRES            0x1
#define VBE_DISPI_INDEX_YRES            0x2
#define VBE_DISPI_INDEX_BPP             0x3
#define VBE_DISPI_INDEX_ENABLE          0x4
#define VBE_DISPI_INDEX_BANK            0x5
#define VBE_DISPI_INDEX_VIRT_WIDTH      0x6
#define VBE_DISPI_INDEX_VIRT_HEIGHT     0x7
#define VBE_DISPI_INDEX_X_OFFSET        0x8
#define VBE_DISPI_INDEX_Y_OFFSET        0x9

#define VBE_DISPI_DISABLED              0x00
#define VBE_DISPI_ENABLED               0x01
#define VBE_DISPI_GETCAPS               0x02
#define VBE_DISPI_8BIT_DAC              0x20
#define VBE_DISPI_LFB_ENABLED           0x40
#define VBE_DISPI_NOCLEARMEM            0x80

void vbe_write(USHORT index, USHORT value)
{
   WRITE_PORT_USHORT(VBE_DISPI_IOPORT_INDEX, index);
   WRITE_PORT_USHORT(VBE_DISPI_IOPORT_DATA, value);
}


void vbe_set(USHORT xres, USHORT yres, USHORT bpp)
{
   vbe_write(VBE_DISPI_INDEX_ENABLE, VBE_DISPI_DISABLED);
   vbe_write(VBE_DISPI_INDEX_XRES, xres);
   vbe_write(VBE_DISPI_INDEX_YRES, yres);
   vbe_write(VBE_DISPI_INDEX_BPP, bpp);
   vbe_write(VBE_DISPI_INDEX_ENABLE, VBE_DISPI_ENABLED | VBE_DISPI_LFB_ENABLED);   
}