common/applications/sensors/prox_gesture/main.c File Reference

Common Sensor Service Proximity Sensor Gesture Recognition Example.

Copyright (c) 2012-2018 Microchip Technology Inc. and its subsidiaries.

#include <stdio.h>
#include <asf.h>
#include <led.h>

Macros
#define	CHAN_1   0x01
#define	CHAN_2   0x02
#define	CHAN_3   0x04
#define	CHAN_NONE   0x00
#define	DOWN_LED   LED1
#define	ERR_BLINK_COUNT   (2) /* Number of times to blink LEDs on error */
#define	LEFT_LED   LED2
#define	PROX_CURRENT_mA   (150) /* Current for proximity sensor LEDs (mA) */
#define	PROX_SAMPLE_RATE   (100) /* Proximity sensor sample rate (Hz) */
#define	PROX_THRESHOLD   (100) /* Manual prox sensor threshold for "near" */
#define	RIGHT_LED   LED3
#define	SET_PROX_CURRENT   (true) /* If true, manually set proximity current */
#define	SET_PROX_THRESHOLD
#define	UP_LED   LED0
#define	USE_PRINTF

Enumerations
enum	direction_t {   UNK = 0,   UP = 1,   DOWN = 2,   LEFT = 3,   RIGHT = 4 }
	Direction code values. More...

Functions
int	main (void)
	Proximity Sensor gesture recognition demo application entry. More...
static void	prox_event_handler (volatile sensor_event_data_t *event_data, volatile void *arg)
	Proximity event handler. More...
static int8_t	test_channels (sensor_data_t *data)
	Proximity value test. More...

Variables
static const char *const	channel_labels [8]
	Strings to indicate which channels detected proximity. More...
direction_t	dir_tbl [8][8]
	Direction lookup table of start_channels (rows) x end_channels (columns) More...
static const char *const	direction_labels [5]
	Strings to display based on gesture direction. More...
sensor_data_t	prox_data = { .scaled = true }
sensor_t	prox_dev
bool	prox_event_occurred = false

#define CHAN_1   0x01

Referenced by test_channels().

#define CHAN_2   0x02

Referenced by test_channels().

#define CHAN_3   0x04

Referenced by test_channels().

#define CHAN_NONE   0x00

Referenced by main(), and test_channels().

#define DOWN_LED   LED1

Referenced by main().

#define ERR_BLINK_COUNT   (2) /* Number of times to blink LEDs on error */

Referenced by main().

#define LEFT_LED   LED2

Referenced by main().

#define PROX_CURRENT_mA   (150) /* Current for proximity sensor LEDs (mA) */

Referenced by main().

#define PROX_SAMPLE_RATE   (100) /* Proximity sensor sample rate (Hz) */

Referenced by main().

#define PROX_THRESHOLD   (100) /* Manual prox sensor threshold for "near" */

Referenced by main().

#define RIGHT_LED   LED3

Referenced by main().

#define SET_PROX_CURRENT   (true) /* If true, manually set proximity current */

#define SET_PROX_THRESHOLD

Value:

(true) /* If true, manually set proximity
                                * threshold */

#define UP_LED   LED0

Referenced by main().

#define USE_PRINTF

Value:

(true) /* If true, output results via serial
                                * terminal */

enum direction_t

Direction code values.

Enumerator
UNK
UP
DOWN
LEFT
RIGHT

int main

(

void

)

Proximity Sensor gesture recognition demo application entry.

This application uses a 3-channel proximity sensor to recognize simple gestures. When a proximity event occurs, the routine will wake up from a low-power sleep mode and begin repeatedly sampling the proximity sensor, until the proximity of the object is no longer detected. Then the beginning and ending sensor readings are compared, and the overall direction of the object's movement is determined based on a lookup table.

Once the direction is determined, it is indicate by turning on one of the LEDs on the controller board and (optionally) by serial output to a terminal device. If the direction cannot be determined, all indicator LEDs will be blinked rapidly.

The application then resets by returning to a low-power sleep mode until the next proximity event is detected.

References sensor_device_t::caps, CHAN_NONE, channel_labels, delay_ms, dir_tbl, direction_labels, DOWN, DOWN_LED, sensor_desc::drv, sensor_desc::err, ERR_BLINK_COUNT, LEFT, LEFT_LED, sensor_caps_t::name, PROX_CURRENT_mA, prox_event_handler(), prox_event_occurred, PROX_SAMPLE_RATE, PROX_THRESHOLD, RIGHT, RIGHT_LED, sensor_add_event(), sensor_attach(), SENSOR_CHANNEL_ALL, sensor_device_id(), sensor_disable_event(), sensor_enable_event(), SENSOR_EVENT_NEAR_PROXIMITY, sensor_get_proximity(), sensor_platform_init(), sensor_set_channel(), sensor_set_current(), sensor_set_sample_rate(), sensor_set_threshold(), SENSOR_THRESHOLD_NEAR_PROXIMITY, SENSOR_TYPE_PROXIMITY, sleepmgr_enter_sleep(), sleepmgr_init(), sleepmgr_lock_mode(), test_channels(), UP, and UP_LED.

static void prox_event_handler ( volatile sensor_event_data_t *  event_data, volatile void *  arg  )

static

Proximity event handler.

This routine will be called when a near-proximity event occurs. It simply copies the proximity data to the sensor_data_t structure specified during the sensor_add_event function call.

This routine executes as part of the interrupt service routine for the sensor interrupt.

References sensor_event_data_t::data, and prox_event_occurred.

Referenced by main().

static int8_t test_channels ( sensor_data_t *  data )

static

Proximity value test.

This routine examines the data fields in the sensor_data_t structure and returns a single value summarizing which channels have a reported proximity value (i.e. the value is not PROXIMITY_NONE).

Parameters

data	Address of sensor_data_t struct containing prox data

Returns

int8_t Encoded with bits set per channel over threshold

References CHAN_1, CHAN_2, CHAN_3, CHAN_NONE, sensor_data_t::proximity, and PROXIMITY_NONE.

Referenced by main().

const char* const channel_labels[8]

static

Initial value:

= {
    "none ",                
    "1    ",                
    "2    ",                
    "1+2  ",                
    "3    ",                
    "1+3  ",                
    "2+3  ",                
    "1+2+3"                 
}

Strings to indicate which channels detected proximity.

Referenced by main().

direction_t dir_tbl[8][8]

Initial value:

=
    
    
    {{  UNK,   UNK,   UNK,    UNK,   UNK,   UNK,   UNK,   UNK   },   
     {  UNK,   UNK,   RIGHT,  UNK,   DOWN,  UNK,   DOWN,  DOWN  },   
     {  UNK,   LEFT,  UNK,    UNK,   LEFT,  LEFT,  UNK,   LEFT  },   
     {  UNK,   UNK,   UNK,    UNK,   DOWN,  UNK,   DOWN,  UNK   },   
     {  UNK,   UP,    RIGHT,  UP,    UNK,   UNK,   RIGHT, UP    },   
     {  UNK,   UP,    RIGHT,  RIGHT, DOWN,  UNK,   RIGHT, RIGHT },   
     {  UNK,   UP,    RIGHT,  UP,    LEFT,  LEFT,  UNK,   UNK   },   
     {  UNK,   UP,    RIGHT,  UNK,   DOWN,  LEFT,  UNK,   UNK   }}

Direction lookup table of start_channels (rows) x end_channels (columns)

Referenced by main().

const char* const direction_labels[5]

static

Initial value:

= {
    "Unknown",
    "Up     ",
    "Down   ",
    "Left   ",
    "Right  "
}

Strings to display based on gesture direction.

Referenced by main().

sensor_data_t prox_data = { .scaled = true }

Referenced by main(), and sfh7770_calibrate().

sensor_t prox_dev

Referenced by main().

bool prox_event_occurred = false

Referenced by main(), prox_event(), and prox_event_handler().