KEYSCAN - Keyboard Scan

Description

Keyscan (KEYSCAN) Peripheral API.

This module contains functions to control the KEYSCAN peripheral of Silicon Labs 32-bit MCUs and SoCs. The KEYSCAN module connects through rows and columns of GPIOs to an external mechanical keypad.

Data Structures

struct sl_keyscan_config_t
KEYSCAN configuration structure.

Functions

void sl_keyscan_init (const sl_keyscan_config_t *p_config)
Initializes KEYSCAN module.
void sl_keyscan_enable (void)
Enables KEYSCAN module.
void sl_keyscan_disable (void)
Disables KEYSCAN module.
void sl_keyscan_wait_ready (void)
Waits for the KEYSCAN to complete reseting or disabling procedure.
void sl_keyscan_wait_sync (void)
Waits for the KEYSCAN to complete all synchronization of register changes and commands.
void sl_keyscan_start_scan (void)
Starts KEYSCAN scan.
void sl_keyscan_stop_scan (void)
Stops the KEYSCAN scan.
void sl_keyscan_reset (void)
Restores KEYSCAN to its reset state.
uint32_t sl_keyscan_get_status (void)
Gets KEYSCAN STATUS register value.
void sl_keyscan_enable_interrupts (uint32_t flags)
Enables one or more KEYSCAN interrupts.
void sl_keyscan_disable_interrupts (uint32_t flags)
Disables one or more KEYSCAN interrupts.
void sl_keyscan_clear_interrupts (uint32_t flags)
Clears one or more pending KEYSCAN interrupts.
uint32_t sl_keyscan_get_interrupts (void)
Gets pending KEYSCAN interrupt flags.
uint32_t sl_keyscan_get_enabled_interrupts (void)
Gets enabled and pending KEYSCAN interrupt flags.
void sl_keyscan_set_interrupts (uint32_t flags)
Sets one or more pending KEYSCAN interrupts from Software.

Macros

#define KEYSCAN_CONFIG_DEFAULT
Suggested default values for KEYSCAN configuration structure.

Enumerations

enum sl_keyscan_delay_t {
SL_KEYSCAN_DELAY_2MS = 0,
SL_KEYSCAN_DELAY_4MS ,
SL_KEYSCAN_DELAY_6MS ,
SL_KEYSCAN_DELAY_8MS ,
SL_KEYSCAN_DELAY_10MS ,
SL_KEYSCAN_DELAY_12MS ,
SL_KEYSCAN_DELAY_14MS ,
SL_KEYSCAN_DELAY_16MS ,
SL_KEYSCAN_DELAY_18MS ,
SL_KEYSCAN_DELAY_20MS ,
SL_KEYSCAN_DELAY_22MS ,
SL_KEYSCAN_DELAY_24MS ,
SL_KEYSCAN_DELAY_26MS ,
SL_KEYSCAN_DELAY_28MS ,
SL_KEYSCAN_DELAY_30MS ,
SL_KEYSCAN_DELAY_32MS
}
KEYSCAN configuration delay values.

Function Documentation

sl_keyscan_init()

void sl_keyscan_init ( const sl_keyscan_config_t * p_config )

Initializes KEYSCAN module.

Parameters
[in] p_config A pointer to the KEYSCAN initialization structure variable.

sl_keyscan_enable()

void sl_keyscan_enable ( void )

Enables KEYSCAN module.

sl_keyscan_disable()

void sl_keyscan_disable ( void )

Disables KEYSCAN module.

Note
The disabling of the module could take some time. This function will not wait for the disabling to finish before returning. Use the function sl_keyscan_wait_ready to wait for the module to be fully disable.

sl_keyscan_wait_ready()

void sl_keyscan_wait_ready ( void )
inline

Waits for the KEYSCAN to complete reseting or disabling procedure.

sl_keyscan_wait_sync()

void sl_keyscan_wait_sync ( void )
inline

Waits for the KEYSCAN to complete all synchronization of register changes and commands.

sl_keyscan_start_scan()

void sl_keyscan_start_scan ( void )
inline

Starts KEYSCAN scan.

Note
This function will send a start command to the KEYSCAN peripheral. The sl_keyscan_wait_sync function can be used to wait for the start command to be executed.
This function requires the KEYSCAN to be enabled.

sl_keyscan_stop_scan()

void sl_keyscan_stop_scan ( void )
inline

Stops the KEYSCAN scan.

Note
This function will send a stop command to the KEYSCAN peripheral. The sl_keyscan_wait_sync function can be used to wait for the stop command to be executed.
This function requires the KEYSCAN to be enabled.

sl_keyscan_reset()

void sl_keyscan_reset ( void )

Restores KEYSCAN to its reset state.

Note
The resetting of the module could take some time. This function will not wait for the resetting to finish before returning. Use the function sl_keyscan_wait_ready to wait for the module to be fully reset.
The register STATUS get reset value after enabling the module because it is of type RSYNC

sl_keyscan_get_status()

uint32_t sl_keyscan_get_status ( void )
inline

Gets KEYSCAN STATUS register value.

Returns
Current STATUS register value.

sl_keyscan_enable_interrupts()

void sl_keyscan_enable_interrupts ( uint32_t flags )
inline

Enables one or more KEYSCAN interrupts.

Note
Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. To ignore a pending interrupt, consider using sl_keyscan_clear_interrupts prior to enabling the interrupt.
Parameters
[in] flags KEYSCAN interrupt sources to enable. Use a set of interrupt flags OR-ed together to set multiple interrupt sources.

sl_keyscan_disable_interrupts()

void sl_keyscan_disable_interrupts ( uint32_t flags )
inline

Disables one or more KEYSCAN interrupts.

Parameters
[in] flags KEYSCAN interrupt sources to disable. Use a set of interrupt flags OR-ed together to disable multiple interrupt sources.

sl_keyscan_clear_interrupts()

void sl_keyscan_clear_interrupts ( uint32_t flags )
inline

Clears one or more pending KEYSCAN interrupts.

Parameters
[in] flags KEYSCAN interrupt sources to clear. Use a set of interrupt flags OR-ed together to clear multiple interrupt sources.

sl_keyscan_get_interrupts()

uint32_t sl_keyscan_get_interrupts ( void )
inline

Gets pending KEYSCAN interrupt flags.

Note
Event bits are not cleared by using this function.
Returns
Pending KEYSCAN interrupt sources. Returns a set of interrupt flags OR-ed together for multiple interrupt sources.

sl_keyscan_get_enabled_interrupts()

uint32_t sl_keyscan_get_enabled_interrupts ( void )
inline

Gets enabled and pending KEYSCAN interrupt flags.

Useful for handling more interrupt sources in the same interrupt handler.

Note
Interrupt flags are not cleared by using this function.
Returns
Pending and enabled KEYSCAN interrupt sources. The return value is the bitwise AND of
  • the enabled interrupt sources in KEYSCAN_IEN and
  • the pending interrupt flags KEYSCAN_IF.

sl_keyscan_set_interrupts()

void sl_keyscan_set_interrupts ( uint32_t flags )
inline

Sets one or more pending KEYSCAN interrupts from Software.

Parameters
[in] flags KEYSCAN interrupt sources to set to pending. Use a set of interrupt flags OR-ed together to set multiple interrupt sources.

Macro Definition Documentation

KEYSCAN_CONFIG_DEFAULT

#define KEYSCAN_CONFIG_DEFAULT
Value:
{ \
0x1387F, /* Clock divider default value = 79999. */ \
3u, /* 3 columns by default. */ \
6u, /* 6 rows by default. */ \
SL_KEYSCAN_DELAY_2MS, /* value 0 = 2ms Scan Delay*/ \
SL_KEYSCAN_DELAY_2MS, /* value 0 = 2ms Debounce Delay */ \
SL_KEYSCAN_DELAY_2MS, /* value 0 = 2ms Row Stable Delay */ \
false, /* Multi-press by default.*/ \
false, /* No auto-start by default. */ \
}

Suggested default values for KEYSCAN configuration structure.

Enumeration Type Documentation

sl_keyscan_delay_t

KEYSCAN configuration delay values.

Enumerator
SL_KEYSCAN_DELAY_2MS

2 ms delay.

SL_KEYSCAN_DELAY_4MS

4 ms delay.

SL_KEYSCAN_DELAY_6MS

6 ms delay.

SL_KEYSCAN_DELAY_8MS

8 ms delay.

SL_KEYSCAN_DELAY_10MS

10 ms delay.

SL_KEYSCAN_DELAY_12MS

12 ms delay.

SL_KEYSCAN_DELAY_14MS

14 ms delay.

SL_KEYSCAN_DELAY_16MS

16 ms delay.

SL_KEYSCAN_DELAY_18MS

18 ms delay.

SL_KEYSCAN_DELAY_20MS

20 ms delay.

SL_KEYSCAN_DELAY_22MS

22 ms delay.

SL_KEYSCAN_DELAY_24MS

24 ms delay.

SL_KEYSCAN_DELAY_26MS

26 ms delay.

SL_KEYSCAN_DELAY_28MS

28 ms delay.

SL_KEYSCAN_DELAY_30MS

30 ms delay.

SL_KEYSCAN_DELAY_32MS

32 ms delay.