HP dx7300 5.6.2 Pointing Device Interface Operation, 5.6.3 Keyboard/Pointing Device Interface Programming, 8042 Configuration, Table 5-13. (Continued)

			Input/Output Interfaces
	Table 5-13. (Continued)
	8042-To-Keyboard Commands
Command	Value	Description
Set Keys—Make/Brake	F8h	Clears keyboard buffer	and sets default scan code set. [1]
Set Keys—Make	F9h	Clears keyboard buffer	and sets default scan code set. [1]
Set Keys—	FAh	Clears keyboard buffer	and sets default scan code set. [1]
Typematic/Make/Brake
Set Type Key—Typematic	FBh	Clears keyboard buffer and prepares to receive key ID. [1]
Set Type Key—Make/Brake	FCh	Clears keyboard buffer and prepares to receive key ID. [1]
Set Type Key—Make	FDh	Clears keyboard buffer and prepares to receive key ID. [1]
Resend	FEh	8042 detected error in keyboard transmission.
Reset	FFh	Resets program, runs keyboard BAT, defaults to Mode 2.

Note: [1] Used in Mode 3 only.

5.6.2 Pointing Device Interface Operation

The pointing device (typically a mouse) connects to a 6-pin DIN-type connector that is identical to the keyboard connector both physically and electrically. The operation of the interface (clock and data signal control) is the same as for the keyboard. The pointing device interface uses the IRQ12 interrupt.

5.6.3 Keyboard/Pointing Device Interface Programming

Programming the keyboard interface consists of configuration, which occurs during POST, and control, which occurs during runtime.

8042 Configuration

The keyboard/pointing device interface must be enabled and configured for a particular speed before it can be used. Enabling and speed parameters of the 8042 logic are affected through the PnP configuration registers of the SCH5317 I/O controller. Enabling and speed control are automatically set by the BIOS during POST but can also be accomplished with the Setup utility and other software.

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