EAX = VDD_SET_BUSY_FLAG_ADDR equate (89H)
EBX = Magic Number
CX = the bitmask (set to 1) for the BUSY bit within the byte.
SI:DI = Selector:Offset address of byte containing the DIB engine BUSY bit in the display driver's PDEVICE structure.
Nothing returned.
This function is for internal use by GDI only. Any other use will cause Windows and the display subsytem to become unstable.
This function calls no mini-VDD functions.