Int 1A Fn B18C - Intel PCi BIOS V2.0c - Write Configuration Word (32-bit [X] AX = B18Ch BL = bus number BH = device/function number (bits 7-3 device, bits 2-0 function) DI = register number (multiple of 2 less than 0100h) CX = word to write Return: as for AX=B10Ch See Also: AX=B10Ch