PI8042_KEYBOARD_ISR callback function (ntdd8042.h)

Article
02/22/2024

A PI8042_KEYBOARD_ISR-typed callback routine customizes the operation of the I8042prt keyboard ISR.

Syntax

PI8042_KEYBOARD_ISR Pi8042KeyboardIsr;

BOOLEAN Pi8042KeyboardIsr(
  [in]  PVOID IsrContext,
  [in]  PKEYBOARD_INPUT_DATA CurrentInput,
  [in]  POUTPUT_PACKET CurrentOutput,
  [in]  UCHAR StatusByte,
  [in]  PUCHAR Byte,
  [out] PBOOLEAN ContinueProcessing,
  [in]  PKEYBOARD_SCAN_STATE ScanState
)
{...}

Parameters

[in] IsrContext

Pointer to the filter device object of the driver that supplies a callback.

[in] CurrentInput

Pointer to the input KEYBOARD_INPUT_DATA structure that is being constructed by the ISR.

[in] CurrentOutput

Pointer to an OUTPUT_PACKET structure, which specifies an array of bytes that is being written to the hardware device.

[in] StatusByte

Specifies the status byte that is read from I/O port 60 when an interrupt occurs.

[in] Byte

Specifies the data byte that is read from I/O port 64 when an interrupt occurs.

[out] ContinueProcessing

Specifies, if TRUE, that processing in the I8042prt keyboard ISR will continue after this callback completes. Otherwise, processing does not continue.

[in] ScanState

Pointer to a KEYBOARD_SCAN_STATE enumeration value, which identifies the keyboard scan state.

Return value

A PI8042_KEYBOARD_ISR callback returns TRUE if the I8042prt keyboard ISR should continue; otherwise it returns FALSE.

Remarks

A PI8042_KEYBOARD_ISR callback is not needed if the default operation of the I8042prt keyboard ISR is sufficient.

An optional, vendor-supplied, upper-level keyboard filter driver can provide a PI8042_KEYBOARD_ISR callback. The I8042prt ISR calls the callback after it validates the interrupt and reads the scan code.

The PI8042_KEYBOARD_ISR callback runs in kernel mode at the IRQL of the I8042prt keyboard ISR.

Requirements

Requirement	Value
Target Platform	Desktop
Header	ntdd8042.h (include Ntdd8042.h)
IRQL	See Remarks section.