Description

This page describes the Keyboard interface which provides access to the keyboard.

A module that implements this interface must map scancodes to virtual keys and these virtual keys to characters.

To do so, the module must use mapping tables from a module that implements the KbdLayout interface.

Besides that, the module must control keyboard leds (CapsLock, NumLock, ScrollLock).

Structures

typedef struct {
    unsigned int type;
    unsigned short charCode;
    unsigned char vKey;
    unsigned char reserved;
    unsigned int flags;
    unsigned int reserved2[5];
} Keyboard_Event;

type values between 0x00-0x0f are reserved for keyboard.

Currently this types are defined:

scancode is the value read from the keyboard, charCode is the character code in Unicode, zero if it doesn't exist and flags has shifts states (ctrl, shift, alt, etc) and will be the sum of:

• 0x001 - Scrolllock on
• 0x002 - Numlock on
• 0x004 - Capslock on
• 0x008 - Left shift pressed
• 0x010 - Right shift pressed
• 0x020 - Left ctrl pressed
• 0x040 - Right ctrl pressed
• 0x080 - Left alt pressed
• 0x100 - Right alt pressed
• 0x200 - Macro pressed

vKey is a virtual key, which can be:

Many virtual keys have a different meaning depending on the keyboard layout.

typedef struct {
    unsigned short interSize;
    unsigned short impSize;
    char names[1];
} Keyboard_LayoutInfo;

Where interSize it's the size of the name of the interface including the terminating zero, impSize it's the size of the name of the implementation including the terminating zero and names it's the area where the names are, first the name of the interface followed by the name of the implementation.

Configuration

This interface defines the following groups and keys available using the CfgManager interface:

These functions are exclusive for system modules.

0x00 - GetLayout

Syntax

const char *Keyboard_GetLayout(void);

Properties

• System
• Phase 1

Description

This function gets the name of the implementation of the KbdLayout interface that is been used by the keyboard.

Return value

The name of the implementation or NULL in case of error.

0x01 - SetLayout

Syntax

int Keyboard_SetLayout(const char *imp);

Properties

• System
• Phase 1

Description

This function sets the keyboard layout to imp, which is the name of a KbdLayout interface implementation.

Return value

• E_OK - Success
• E_BAD_VALUE - Invalid argument
• E_MODULE - Error using module imp
• E_NO_MEMORY - Not enough memory available

These functions were designed for user modules.

0x02 - UGetLayout

Syntax

int Keyboard_UGetLayout(Keyboard_LayoutInfo *info, unsigned int size);

Properties

User modules

Description

This function gets informations about the implementation of the KbdLayout interface that is been used by the keyboard.

size it's the total size of info.

In case of success, info will be filled with the informations.

Return value

• E_OK - Success
• E_BAD_VALUE - Invalid argument
• E_NOT_REGISTERED - No output device registered
• E_TOO_BIG - The size of info is not enough
• E_FAULT - Memory access violation

0x03 - USetLayout

Syntax

int Keyboard_USetLayout(const char *imp);

Properties

User modules

Description

This function sets the keyboard layout to imp, which is the name of a KbdLayout interface implementation.

Return value

• E_OK - Success
• E_BAD_VALUE - Invalid argument
• E_NOT_REGISTERED - No output device registered
• E_FAULT - Memory access violation
• E_MODULE - Error using module imp
• E_NO_MEMORY - Not enough memory available