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NdisImmediateReadPortUshort

This function is obsolete for Windows XP and later. Windows XP supports this function for legacy drivers; however, the Windows XP DDK will not build an NDIS driver that calls this function. Drivers should call NdisReadPortUshort instead.

NdisImmediateReadPortUshort reads a USHORT from a given bus-relative I/O port.

VOID
  NdisImmediateReadPortUshort(
    IN NDIS_HANDLE  WrapperConfigurationContext,
    IN ULONG  Port,
    OUT PUSHORT  Data
    );

Parameters

WrapperConfigurationContext
Specifies the handle input to MiniportInitialize.
Port
Specifies the bus-relative I/O port address.
Data
Pointer to a caller-supplied variable in which this function returns the value read from the I/O port.

Headers

Declared in Ndis.h. Include Ndis.h.

Comments

NdisImmediateReadPortUshort determines how the host accesses the given I/O port, maps the bus-relative port address, and then reads a USHORT-type value from the device.

A miniport driver can call NdisImmediateReadPortUshort during initialization to read data from a device I/O port when that driver has not yet called NdisMRegisterIoPortRange to obtain mapped device memory ranges. After its call to NdisMRegisterIoPortRange, the driver uses the faster NdisRawXxx functions to communicate with its NIC.

A miniport driver should not call NdisImmediateReadPortUshort in a Plug and Play environment.

Callers of NdisImmediateReadPortUshort run at IRQL = PASSIVE_LEVEL.

See Also

MiniportInitialize, NdisImmediateReadPortUchar, NdisImmediateReadPortUlong, NdisImmediateWritePortUshort, NdisMRegisterIoPortRange, NdisRawReadPortUshort NdisReadPortUshort