Format of VESA SuperVGA mode information: Offset Size Description ) 00h WORD mode attributes (see #00080) 02h BYTE window attributes, window A (see #00081) 03h BYTE window attributes, window B (see #00081) 04h WORD window granularity in KB 06h WORD window size in KB 08h WORD start segment of window A (0000h if not supported) 0Ah WORD start segment of window B (0000h if not supported) 0Ch DWORD -> FAR window positioning function (equivalent to AX=4F05h) 10h WORD bytes per scan line ---remainder is optional for VESA modes in v1.0/1.1, needed for OEM modes--- 12h WORD width in pixels (graphics) or characters (text) 14h WORD height in pixels (graphics) or characters (text) 16h BYTE width of character cell in pixels 17h BYTE height of character cell in pixels 18h BYTE number of memory planes 19h BYTE number of bits per pixel 1Ah BYTE number of banks 1Bh BYTE memory model type (see #00082) 1Ch BYTE size of bank in KB 1Dh BYTE number of image pages (less one) that will fit in video RAM 1Eh BYTE reserved (00h for VBE 1.0-2.0, 01h for VBE 3.0) ---VBE v1.2+ --- 1Fh BYTE red mask size 20h BYTE red field position 21h BYTE green mask size 22h BYTE green field size 23h BYTE blue mask size 24h BYTE blue field size 25h BYTE reserved mask size 26h BYTE reserved mask position 27h BYTE direct color mode info bit 0: color ramp is programmable bit 1: bytes in reserved field may be used by application ---VBE v2.0+ --- 28h DWORD physical address of linear video buffer 2Ch DWORD pointer to start of offscreen memory 30h WORD KB of offscreen memory ---VBE v3.0 --- 32h WORD bytes per scan line in linear modes 34h BYTE number of images (less one) for banked video modes 35h BYTE number of images (less one) for linear video modes 36h BYTE linear modes: size of direct color red mask (in bits) 37h BYTE linear modes: bit position of red mask LSB (e.g. shift count) 38h BYTE linear modes: size of direct color green mask (in bits) 39h BYTE linear modes: bit position of green mask LSB (e.g. shift count) 3Ah BYTE linear modes: size of direct color blue mask (in bits) 3Bh BYTE linear modes: bit position of blue mask LSB (e.g. shift count) 3Ch BYTE linear modes: size of direct color reserved mask (in bits) 3Dh BYTE linear modes: bit position of reserved mask LSB 3Eh DWORD maximum pixel clock for graphics video mode, in Hz 42h 190 BYTEs reserved (0) Note: while VBE 1.1 and higher will zero out all unused bytes of the buffer, v1.0 did not, so applications that want to be backward compatible should clear the buffer before calling