Specifications

208 AMD Geode™ GeodeROM Functional Specification
Video BIOS Support
32087C
13.2.17 Function 15h: VBE Display Data Channel
Description:
This optional function provides a mechanism to extract data from attached display devices on the VESA communica-
tion channel.
Passed:
Returns:
13.2.18 Function 16h: Graphics System Configuration (GC)
The video BIOS does not implement this function.
13.2.19 VBE Data Structures
VbeinfoBlock struc
VbeSignature db ‘VESA’ ;VBE Signature
Vbe Version dw 0200h ;VBE Version
OemStringPtr dd ? ;Pointer to OEM String
Capabilities db 4 dup (?);Capabilities of graphics controller
VideoMode Ptr dd ? ;Pointer to Video Mode List
TotalMemory dw ? ;Number of 64 KB memory blocks
;Added for VBE 2.0
OemSoftwareRev dw ? ;VBE implementation Software revision
OemVendorNamePtr dd ? ;Pointer to Vendor Name String
OemProductNamePtr dd ? ;Pointer to Product Name String
OemProductRevPtr dd ? ;Pointer to Product Revision String
Reserved db 222 dup (?);Reserved for VBE implementation scratch area
OemData db 256 dup (?);Data Area for OEM Strings
VbeInfoBlock ends
Parameter Description
AH 4F14h
AL 15h
BL Subfunction
CX Controller ID (00h = Primary controller)
DX Block number (00h in version)
ES:DI Pointer to 128-byte buffer (if BL = 01h, 02h)
Parameter Description
AX VBE Return Status
BH Approximate time in seconds to transfer EDID
BL DDC level supported