Pointing Device Interface Operation; Keyboard/Pointing Device Interface Programming - HP dx7300 Technical Reference Manual

Command
Set Keys—Make/Brake
Set Keys—Make
Set Keys—
Typematic/Make/Brake
Set Type Key—Typematic
Set Type Key—Make/Brake
Set Type Key—Make
Resend
Reset
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.
Technical Reference Guide
Table 5-13. (Continued)
8042-To-Keyboard Commands
Value Description
F8h Clears keyboard buffer and sets default scan code set. [1]
F9h Clears keyboard buffer and sets default scan code set. [1]
FAh Clears keyboard buffer and sets default scan code set. [1]
FBh Clears keyboard buffer and prepares to receive key ID. [1]
FCh Clears keyboard buffer and prepares to receive key ID. [1]
FDh Clears keyboard buffer and prepares to receive key ID. [1]
FEh 8042 detected error in keyboard transmission.
FFh Resets program, runs keyboard BAT, defaults to Mode 2.
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Input/Output Interfaces
5-17