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VPICD_IRQ_Descriptor  STRUC
    VID_IRQ_Number       dw   ?
    VID_Options          dw   0
    VID_Hw_Int_Proc      dd   ?
    VID_Virt_Int_Proc    dd   0
    VID_EOI_Proc         dd   0
    VID_Mask_Change_Proc dd   0
    VID_IRET_Proc        dd   0
    VID_IRET_Time_Out    dd   500
VPICD_IRQ_Descriptor  ENDS
 
The VPICD_IRQ_Descriptor structure contains information about a virtualized
IRQ.
 
Member                Description
────────────────────────────────────────────────────────────────────────────
 
VID_IRQ_Number        Specifies the number of the IRQ to virtualize.
 
VID_Options           Specifies the options for virtualizing the IRQ. It can
                      be a combination of the following values:
 
                      Value                  Meaning
                      ──────────────────────────────────────────────────────
                      VPICD_Opt_Read_Hw_IRR  Reads the hardware interrupt
                                             register.
 
                      VPICD_Opt_Can_Share    Virtual IRQ can be shared.
 
VID_Hw_Int_Proc       Points to the callback procedure that handles hardware
                      interrupts for this IRQ.
 
VID_Virt_Int_Proc     Points to the callback procedure that handles virtual
                      interrupts for this IRQ.
 
VID_EOI_Proc          Points to the callback procedure that handles
                      end-of-interrupt commands for this IRQ.
 
VID_Mask_Change_Proc  Points to the callback procedure that handles changes
                      to the IRQ mask for this IRQ.
 
VID_IRET_Proc         Points to the callback procedure that handles iret
                      instructions for this IRQ.
 
VID_IRET_Time_Out     Specifies the maximum amount of time in milliseconds
                      that the virtual PIC device allows before the time-out
                      occurs.
 
Comments
 
Time-outs are very important to prevent 386 enhanced mode Windows from
hanging while simulating a hardware interrupt.
 
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