IO_DES structure (cfgmgr32.h)

The IO_DES structure is used for specifying either a resource list or a resource requirements list that describes I/O port usage for a device instance. For more information about resource lists and resource requirements lists, see Hardware Resources.

Syntax

typedef struct IO_Des_s {
  DWORD     IOD_Count;
  DWORD     IOD_Type;
  DWORDLONG IOD_Alloc_Base;
  DWORDLONG IOD_Alloc_End;
  DWORD     IOD_DesFlags;
} IO_DES, *PIO_DES;

Members

IOD_Count

For a resource list:

Zero.

For a resource requirements list:

The number of elements in the IO_RANGE array that is included in the IO_RESOURCE structure.

IOD_Type

Must be set to the constant value IOType_Range.

IOD_Alloc_Base

For a resource list:

The lowest-numbered of a range of contiguous I/O port addresses allocated to the device.

For a resource requirements list:

Zero.

IOD_Alloc_End

For a resource list:

The highest-numbered of a range of contiguous I/O port addresses allocated to the device.

For a resource requirements list:

Zero.

IOD_DesFlags

One bit flag from each of the flag sets described in the following table.

	Flag	Definition
Port Type Flags
	fIOD_IO	The device is accessed in I/O address space.
	fIOD_Memory	The device is accessed in memory address space.
	fIOD_PortType	Bitmask for the bits within IOD_DesFlags that specify the port type value.
Decode Flags
	fIOD_10_BIT_DECODE	The device decodes 10 bits of the port address.
	fIOD_12_BIT_DECODE	The device decodes 12 bits of the port address.
	fIOD_16_BIT_DECODE	The device decodes 16 bits of the port address.
	fIOD_POSITIVE_DECODE	The device uses "positive decode" instead of "subtractive decode."
	fIOD_DECODE	Bitmask for the bits within IOD_DesFlags that specify the decode value.

Requirements

Requirement	Value
Header	cfgmgr32.h (include Cfgmgr32.h)

See also

IO_RANGE

IO_RESOURCE