Keypad Driver

Keypad Overview

This is the keypad driver which detect key presses, and provide the necessary data to the microcontroller or the main program.
The keypad debounce time, keypad action, and key press time should be in the application side.

Usage

The API functions have the first argument as the strucure instance and next followed by config structure.

Configure keypad pins in keypad driver module open function.

When a key press is detected, an rcb callback function will be called to perform further actions with the pressed keys.

Return codes of API functions are defined in header file.

Application Interface

The below table captures the functions that are to be called from the application layer.

Keypad calls
Function	Description
rs_keypad_open	Function to open the keypad module
rs_keypad_process	Function to process the keypad driver module

Callback Functions
Function	Description
rcb_keypad_action	Callback function gets keypad action and use for further need.

Error Code

Every API’s for the keyad module returns some success or failure values. Please refer below section,

RAPIDSEA ERROR CODES

Keypad driver module Header Details

Documentation from the relevant header as follows:

Keypad Module.

This file contains the APIs for Keypad module

Author
Embien RAPIDSEA Team

Copyright
Embien Technologies India Pvt. Ltd.

Defines

RS_KEYPAD_MAX_NUM_KEYS

Maximum number of keys supported.

RS_KEY_IDLE_STATE

Macros for key state Key is in the idle state, not pressed

RS_KEY_PRESSED

Key is in the pressed state

RS_KEY_LONG_PRESSED

Key has been held down long enough to trigger a long press action

RS_KEY_RELEASED

Key has been released after being pressed

RS_KEY_WAIT_FOR_DEBOUNCE

Key is waiting for debounce time to stabilize the input signal

RS_KEYPAD_ACTION_PRESSED

Macros for key action Action indicating that a key has been pressed

RS_KEYPAD_ACTION_LONG_PRESSED

Action indicating that a key has been long-pressed

RS_KEYPAD_ACTION_RELEASED

Action indicating that a key has been released

RS_LONG_PRESS_TIME_INCREMENT_MS

Time increment in milliseconds for a long press action.

Typedefs

typedef struct tag_rs_key_config rs_key_config_t

Contains configuration information for a key.

typedef struct tag_rs_keypad_config rs_keypad_config_t

Contains information about keypad config.

typedef struct tag_rs_key_info rs_key_info_t

Contains information about keys state.

typedef struct tag_rs_keypad_instance rs_keypad_instance_t

Contains information about keypad instance.

Functions

rs_handle_t rs_keypad_open(rs_keypad_instance_t *ptr_keypad_inst, rs_keypad_config_t *ptr_keypad_config)

Open and initialize the keypad.

This function initializes the keypad instance with the given configuration. It sets up the necessary hardware and software components to make the keypad ready for use.

Open and initialize the keypad.

Parameters:

ptr_keypad_inst – [in] - Pointer to the keypad instance structure

ptr_keypad_config – [in] - Pointer to the keypad configuration structure

Returns:

Handle to the keypad instance or an error code

rs_ret_val_t rs_keypad_process(rs_handle_t keypad_handle)

Process the keypad inputs.

This function processes the current state of the keypad, updating the internal state and handling key presses or idles as needed.

Parameters:

keypad_handle – [in] - Handle to the keypad instance

Returns:

0 on success or error code

rs_ret_val_t rs_keypad_close(rs_handle_t keypad_handle)

Close the keypad instance.

This function closes the keypad instance, releasing any resources and shutting down the keypad.

Parameters:

keypad_handle – [in] - Handle to the keypad instance

Returns:

0 on success or error code

struct tag_rs_key_config

#include <rs_keypad.h>

Contains configuration information for a key.

Public Members

uint16_t port_id_key

Port ID associated with the key.

uint16_t pin_id_key

Pin ID associated with the key.

struct tag_rs_keypad_config

#include <rs_keypad.h>

Contains information about keypad config.

Public Members

uint16_t num_keys

Maximum number of keys used.

uint16_t debounce_time

Debounce Time for inputs in milliseconds.

uint16_t long_press_time

Long press time for keys in milliseconds.

rs_key_config_t key_config[RS_KEYPAD_MAX_NUM_KEYS]

Array holding port and pin information for up to 16 keys.

struct tag_rs_key_info

#include <rs_keypad.h>

Contains information about keys state.

Public Members

uint8_t key_state

Current state of the key (e.g., pressed, released)

uint8_t last_read

Last read state of the key.

uint8_t long_press_count

Times the long key pressed.

uint32_t initial_time

Timestamp when the key was initially pressed.

struct tag_rs_keypad_instance

#include <rs_keypad.h>

Contains information about keypad instance.

Public Members

rs_keypad_config_t *ptr_config

Pointer to the keypad configuration structure.

rs_key_info_t key_info[RS_KEYPAD_MAX_NUM_KEYS]

Array holding information for up to 16 keys.

void *ptr_arg

User Argument.