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NdisImmediateWritePortUchar function

Note   NDIS 5. x has been deprecated and is superseded by NDIS 6. x. For new NDIS driver development, see Network Drivers Starting with Windows Vista. For information about porting NDIS 5. x drivers to NDIS 6. x, see Porting NDIS 5.x Drivers to NDIS 6.0.

NdisImmediateWritePortUchar writes a byte to a given bus-relative I/O port.

Syntax

VOID NdisImmediateWritePortUchar(
  _In_ NDIS_HANDLE WrapperConfigurationContext,
  _In_ ULONG       Port,
  _In_ UCHAR       Data
);

Parameters

  • WrapperConfigurationContext [in]
    Specifies the handle input to MiniportInitialize.

  • Port [in]
    Specifies the bus-relative I/O port address.

  • Data [in]
    Specifies the caller-supplied byte value to write to the I/O port.

Return value

None

Remarks

NdisImmediateWritePortUchar determines how the host accesses the given I/O port, maps the bus-relative port address, and then writes the given byte to the device.

A miniport driver can call NdisImmediateWritePortUchar during initialization to write data to 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 NdisImmediateWritePortUchar in a Plug and Play environment.

Requirements

Target platform

Universal

Version

Not supported for NDIS 6.0 drivers in Windows Vista. Supported for NDIS 5.1 drivers in Windows Vista and Windows XP. 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 NdisWritePortUcharinstead.

Header

Ndis.h (include Ndis.h)

Library

Ndis.lib

IRQL

PASSIVE_LEVEL

See also

MiniportInitialize

NdisImmediateReadPortUchar

NdisImmediateWritePortUlong

NdisImmediateWritePortUshort

NdisMRegisterIoPortRange

NdisRawWritePortUchar

NdisWritePortUchar

 

 

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