PI8042_SYNCH_WRITE_PORT function pointer

The PI8042_SYNCH_READ_PORT-typed callback routine does a synchronized write to an i8042 port. I8042prt supplies this routine.

Syntax


typedef NTSTATUS ( *PI8042_SYNCH_WRITE_PORT)(
  _In_  PVOID Context,
  _In_  UCHAR Value,
  _In_  BOOLEAN WaitForACK
);

Parameters

Context [in]

Pointer to a context supplied by I8042prt.

Value [in]

Specifies the UCHAR value to write to an i8042 port.

WaitForACK [in]

Specifies, if TRUE, that the routine waits until the write is acknowledged by the i8042 port. Otherwise, the routine returns without waiting for an acknowledgment from the port.

Return value

The PI8042_SYNCH_WRITE_PORT callback returns one of the following status values:

Return codeDescription
STATUS_SUCCESS

The routine successfully wrote a byte to an i8042 port.

STATUS_IO_TIMEOUT

The hardware was not ready for a write access.

 

Remarks

The PI8042_SYNCH_READ_PORT callback can only be used in a PI8042_KEYBOARD_INITIALIZATION_ROUTINE callback. I8042prt specifies the write port callback in the WritePort parameter that I8042prt inputs to a keyboard initialization routine.

The routine polls the hardware until a read is returned by the hardware or an internal time-out occurs.

Requirements

Header

Ntdd8042.h (include Ntdd8042.h)

IRQL

PASSIVE_LEVEL

See also

PI8042_KEYBOARD_INITIALIZATION_ROUTINE
PI8042_SYNCH_READ_PORT

 

 

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