Collaboration diagram for Keypad driver:

Data Structures
struct	key_repeat_t
	The structure defines key repeat parameters. More...

struct	key_combi_t
	The structure defines combi key parameters. Note that it is possible to define individual debounce time for each group. Thus it is also the way to define an individual key with debouncing which differs from default KEY_PRELL_TIME : just define a "group of 1 key. More...

Enumerations

Functions called from application programs
void	StartKeyScan (void)
	Start Keys scanning. More...

void	KeyInterruptCb (void)
	This callback function must be called when a key interrupt is received by the platform. More...

void	KeyDebounceTimeSet (uint16_t Time)
	Sets key debounce time. Default time is KEY_PRELL_TIME. More...

bool	KeyStatusGet (uint8_t KeyIndex)
	Returns status of debounced key. More...

Application' keypad configuration and supplied functions.
The following is the keypad driver setup for application's board.h and board.c files.
struct key_repeat_t	ConfigKeyRepeat [NUMBER_OF_REPEAT_KEYS]
	User defined array of key_repeat_t structures defines key repeat parameters.

struct key_combi_t	ConfigKeyCombi [NUMBER_OF_COMBI_GROUPS]
	User defined array of key_combi_t structures defines combi key groups parameters.

static __inline uint32_t	ReadKeyInput (void)
	Application supplied board-specific callback function for reading key inputs. More...

void	KeyInterruptEnable (bool Enable)
	Application supplied board-specific callback function to enable or disable HW interrupts for all keys. More...

#define	KEY_ENABLED true/false

#define	KEYS_HAVE_NO_INTERRUPT true/false

#define	REPEAT_KEY_ENABLED true/false

#define	REPEAT_KEY_STEP2_ENABLED true/false

#define	COMBI_KEYS_ENABLED true/false

#define	COMBI_KEY_RELEASE_ENABLED true/false

#define	NUMBER_OF_KEYS <N>

#define	NUMBER_OF_REPEAT_KEYS <N>

#define	NUMBER_OF_COMBI_GROUPS <N>

#define	KEY_SIGNAL_RECEIVER <struct process *p>

#define	SCAN_KEY_INTERVAL <T>

#define	KEY_PRELL_TIME <T>

Detailed Description

This driver supports key debounce functionality if KEY_ENABLED is set true. The function KeyInterruptEnable() must be called to enables interrupts for all keys.

The number of scanned keys is given by NUMBER_OF_KEYS. Key debounce time is given by KEY_PRELL_TIME. When debouncing the interval is given by SCAN_KEY_INTERVAL. The keys are read by the inline function ReadKeyInput().

The following events are sent:

The event KEY_PRESSED with keynumber (indexed from 0) is sent when a key is detected pressed
The event KEY_RELEASED with keynumber (indexed from 0) is sent when a key is detected released and a combi event has not been sent which involves this key.
The event COMBI_KEY_RELEASED with keynumber (indexed from 0) is sent when a key is detected released and a combi event has been sent which involves this key, and COMBI_KEY_RELEASE_ENABLED = TRUE.

It is possible to send a repeated event when a key has been pressed for a given time. The event can be repeated at a given interval. This functionality is enabled if REPEAT_KEY_ENABLED is set true: The number of repeated keys is given by NUMBER_OF_REPEAT_KEYS. Repeat function is configured in table "struct key_repeat_t ConfigKeyRepeat[]" in Board.c The following events are sent:

After key has been pressed in "Step1Time" time, the event KEY_REPEAT1 with keynumber (indexed from 0) is sent each "RepeatTime" time
The following function is enabled if REPEAT_KEY_STEP2_ENABLED is set true:
After key has been pressed in "Step2Time" time, the event KEY_REPEAT2 with keynumber (indexed from 0) is sent each "RepeatTime" time

It is possible to send a event when a combination of one or more keys have been pressed for a given time. This functionality is enabled if COMBI_KEYS_ENABLED is set true: The number of combi keys groups is given by NUMBER_OF_COMBI_GROUPS. Combi function is configured in table "struct key_combi_t ConfigKeyCombi[]" in Board.c The following events are sent:

After given time the event COMBI_KEY_PRESSED with combi key group number (indexed from 0) is sent

All events are sent to process defined by KEY_SIGNAL_RECEIVER

Enumeration Type Documentation

enum key_events_t

Event numbers being sent to the application process. Event's void *data field contains key number.

Enumerator
KEY_PRESSED	Key was pressed.
KEY_RELEASED	Key was released.
KEY_REPEAT1	Key press repeat after Step1Time.
KEY_REPEAT2	Key press repeat after Step2Time.
COMBI_KEY_PRESSED	Key combination was pressed.
COMBI_KEY_RELEASED	Key combination was released.
EVENT_KEY__LAST	Gives the size of allocated event numbers.

Definition at line 118 of file key.h.

Function Documentation

void StartKeyScan ( void )

Start Keys scanning.

Only used if KEYS_HAVE_NO_INTERRUPT = true

void KeyInterruptCb ( void )

This callback function must be called when a key interrupt is received by the platform.

Only used if KEYS_HAVE_NO_INTERRUPT == false

void KeyDebounceTimeSet ( uint16_t Time )

Sets key debounce time. Default time is KEY_PRELL_TIME.

Parameters

Time	New debounce time in ms

bool KeyStatusGet ( uint8_t KeyIndex )

Returns status of debounced key.

Parameters

KeyIndex key number from 0 to (NUMBER_OF_KEYS - 1)

Returns: true if key pressed, else false

static __inline uint32_t ReadKeyInput ( void )

static

Application supplied board-specific callback function for reading key inputs.

The driver calls this function in order to get current keys status. It is an application responsibility to map actual internal GPIO or GPIO extender port pins to an int32_t array of bits used as key status in the driver.

Example for 2 inverted keys (pressing connects to ground) supporting press/release event generation:

 #define KEY0 0
 #define KEY1 1
 uint32_t LastReadKeyInput;
 static __inline uint32_t ReadKeyInput(void)
 {
   uint32_t KeyInput, KeyData;
   LastReadKeyInput = KeyInput = ~GpioPortGet(); // Pins are inverted!
   KeyData  = ((KeyInput >> KEY0_PIN_NUMBERn) & 1) << KEY0;
   KeyData |= ((KeyInput >> KEY1_PIN_NUMBERn) & 1) << KEY1;
   return KeyData;
 }

Returns: Keys bitmask. Each bit represents a key and settled if the key is currently pressed, cleared if released.

void KeyInterruptEnable ( bool Enable )

Application supplied board-specific callback function to enable or disable HW interrupts for all keys.

This function must be called by application to enable interrupts in interrupt mode (KEYS_HAVE_NO_INTERRUPT == false) before the driver starts to work.

While working the driver uses the function. When a key is pressed/released, the key interrupt will disable further key interrupts, and starts the key debounce scheduler. The interrupts will be re-enabled again when the scheduler is not active.

Only used if KEYS_HAVE_NO_INTERRUPT = false.

Example for 2 inverted keys (pressing connects to ground) supporting press/release event generation:

 uint32_t LastReadKeyInput;
 void KeyInterruptEnable(bool Enable)
 {
   enum irq_mode_t NewMode;
   NewMode = (LastReadKeyInput & (1 << KEY0_PIN_NUMBERn)) ? IRQ_MODE_RISING : IRQ_MODE_FALLING;
   IrqEnableInternal(KEY0_PIN_NUMBERn, Enable ? NewMode : IRQ_MODE_DISABLED);
   NewMode = (LastReadKeyInput & (1 << KEY1_PIN_NUMBERn)) ? IRQ_MODE_RISING : IRQ_MODE_FALLING;
   IrqEnableInternal(KEY1_PIN_NUMBERn, Enable ? NewMode : IRQ_MODE_DISABLED);
 }

Parameters

Enable true to enable interrupts, false to disable interrupts

Data Structures

Enumerations

Functions called from application programs

Application' keypad configuration and supplied functions.

Detailed Description

Enumeration Type Documentation

Function Documentation