File content as of revision 24:1063cfc311e5:

// INTERFACING ADXL345 ACCELEROMETER USING I2C 

/*
NOTE :

ACTIVITY   :  ACCELEROMETER IS ACCELERATING AND ITS VALUES ARE GREATER THAN THE ACTIVITY THRESHOLD
INACTIVITY :  ACCELEROMETER IS NOT IN ACCELERATION OR ACCELERATING VERY SLIGHTLY THAT ITS VALUES ARE BELOW THE INACTIVITY THRESHOLD  
DOUBLE TAP :  SUDDEN JERK CONDITION (IDENIFIED BY SUDDEN VARIATIONS IN THE ACCELERATION VALUES)


Due to communication speed limitations, the maximum output
data rate when using 400 kHz I2C is 800 Hz and scales linearly with
a change in the I2C communication speed

*/
/*
#include "Accelerometer.h"

#define DOUBLE_TAP_INTERRUPT        0x20
#define ACTIVITY_INTERRUPT          0x10
#define INACTIVITY_INTERRUPT        0x08

#define TAP_THRESHOLD               75 
#define ACTIVITY_THRESHOLD          64      // THRES_ACT register value 62.5mg/LSB , therfore value 32 indicates 2g activity
#define INACTIVITY_THRESHOLD        50

#define DUR_TIME                    0x15    // DUR Register value providing maximum time to be held to generate an interrupt
#define LATENT_TIME                 0x15    // The interrupt latency
#define WINDOW_TIME                 0x45    // The time of the interrupt window in which the next tap will be detected 
#define INACTIVITY_VALIDATION_TIME  5       // The time until which the acceleration must be held below the inactivity threshold to generate an inactvity interrupt
                                            // Here the value 5 indicates literally 5 secs
#define X_AXIS_OFFSET               0x7F
#define Y_AXIS_OFFSET               0x7F
#define Z_AXIS_OFFSET               0x05


I2C i2c(PB_9, PB_8);
RawSerial DEBUG_UART1(PA_9, PA_10);//USART1_TX->PA_9,USART1_RX->PA_10

InterruptIn activity(PB_0); 
InterruptIn inactivity(PA_4); // As for now only this is used
DigitalOut led(LED1);

const int slave_address_acc = 0xA6;
char axis_data[6] = {0,0,0,0,0,0};

char interrupt_source[2];
char axis_data_start_address[2] = {0x32, 0};
char intr_source_address[2] = {0x30, 0};
char all_interrupt_clear_command[2] = {0x2E, 0x00};
char all_interrupt_enable_command[2] = {0x2E, 0x38};
char activity_interrupt_disable_command[2] = {0x2E, 0x08};
char inactivity_interrupt_disable_command[2] = {0x2E, 0x30};
char accelerometer_status_registered = 0;
unsigned int interrupt_source_duplicate;

char threshold_offset_command[5];
char act_inact_time_config_command[8];
char interrupt_enable_command[3];
char tap_axis_enable_command[2];
char baud_rate_command[2];
char data_format_command[2];
char measure_bit_on_command[2];


char previous_state = 0;
char current_state = 0;

unsigned char vehicle_speed = 25;                                       // Kmph
unsigned char current_speed, previous_speed, speed_threshold = 10;      // Kmph

unsigned char x_axis, y_axis, z_axis;

unsigned char Motion_Detect_Status = FALSE;
uint8 Accelerometer_Interrupt_Generated = FALSE;
unsigned char Motion_Type_Detected = MOTION_TYPE_UNKNOWN;    //By default set motion type as unknown
void Accelerometer_Process_thread(void const *args) ;

//----------------------------------------------------------------------------------------------------------

// CONVERTS THE CHAR DATA TO UNSIGNED INTERGER DATA

void char_to_int(char data_fetched)
{
    unsigned int shifter;
    interrupt_source_duplicate = 0x00;
    for(shifter = 0; shifter < 8; shifter++)
    {
        interrupt_source_duplicate |= (((data_fetched >> shifter) & 0x01) << shifter); // Converts char data into unsigned int
    }   
}

//----------------------------------------------------------------------------------------------------------

// LEAVE THIS ROUTINE COMMENTED (IT JUST PRINTS THE DATA IN BINARY FORMAT)

void print_data_bits(char data_fetched)
{
    unsigned int shifter;
    for(shifter = 0; shifter < 8; shifter++)
    {
        DEBUG_UART1.printf("%d",((data_fetched&0x80)>>7));
        data_fetched = data_fetched << 1;
    }
    DEBUG_UART1.printf("\r\n\r\n");       
}

//----------------------------------------------------------------------------------------------------------

void get_vehicle_speed(void)
{
    // PASS OBD COMMAND "010D<CR>" AND FETCH THE VEHICLE SPEED AT THIS POINT
}
   

void interrupt_activity_inactivity()
{   
    i2c.write(slave_address_acc, all_interrupt_clear_command, 2);  
    Motion_Detect_Status = TRUE; 
}

//----------------------------------------------------------------------------------------------------------
 //this thread is to send lora packets periodically.
 void Accelerometer_Process_thread(void const *args) 
 {    
    DEBUG_UART1.baud(115200);
    DEBUG_UART1.printf("    Hello\n");
    inactivity.rise(interrupt_activity_inactivity); // Attach the address of interrupt_activity_inactivity function to rising edge
    
    // THE FOLLOWING GROUP OF COMMAND VARIABLES STORES THE CONFIGURATION VALUES TO BE WRITTEN TO THE ADXL345 ACCELEROMETER    
    threshold_offset_command[0] = 0x1D;                 // Threshold Tap Register address
    threshold_offset_command[1] = TAP_THRESHOLD;                   // Threshold tap Register value
    threshold_offset_command[2] = X_AXIS_OFFSET;        // Offset - X axis
    threshold_offset_command[3] = Y_AXIS_OFFSET;        // Offset - Y axis
    threshold_offset_command[4] = Z_AXIS_OFFSET;        // Offset - Z axis
    
    act_inact_time_config_command[0] = 0x21;     // DUR Register address
    act_inact_time_config_command[1] = DUR_TIME;     
    act_inact_time_config_command[2] = LATENT_TIME;     
    act_inact_time_config_command[3] = WINDOW_TIME;     
    act_inact_time_config_command[4] = ACTIVITY_THRESHOLD;       
    act_inact_time_config_command[5] = INACTIVITY_THRESHOLD;        // THRES_INACT Register 
    act_inact_time_config_command[6] = INACTIVITY_VALIDATION_TIME;  // TIME_INACT Register, making inactivity detection time = 5 secs
    act_inact_time_config_command[7] = 0x77;                        // Activity, Inactivity detection enabled for all axis
    
    interrupt_enable_command[0] = 0x2E;     // INT Enable Register address
    interrupt_enable_command[1] = 0x38;     // Enabling Double tap (sudden jerk), Activity & Inactivity Interrupts
    interrupt_enable_command[2] = 0xFF;     // Double tap (sudden jerk), Activity & inactivity interrupts are mapped to INT2 pin
     
    tap_axis_enable_command[0] = 0x2A;     // Address of the TAP_AXES Register
    tap_axis_enable_command[1] = 0x07;     // X, Y & Z axis participate in tap detection
    
    baud_rate_command[0] = 0x2C;     // Address of the BW RATE register
    baud_rate_command[1] = 0x0D;     // Increased the data rate to 800Hz, default is 0x0A indicating 100Hz
            
    data_format_command[0] = 0x31;    // Data format register address
    data_format_command[1] = 0x04;    // Making the acceleration data as left justified
    
    measure_bit_on_command[0] = 0x2D;      // Post the Register address of the slave (Have to write this into slave)
    measure_bit_on_command[1] = 0x08;      // Turn ON the Measure Bit
    
    i2c.write(slave_address_acc, threshold_offset_command, 5);
    i2c.write(slave_address_acc, act_inact_time_config_command, 8);
    i2c.write(slave_address_acc, interrupt_enable_command, 3);
    i2c.write(slave_address_acc, tap_axis_enable_command, 2);
    i2c.write(slave_address_acc, baud_rate_command, 2);
    i2c.write(slave_address_acc, data_format_command, 2);
    i2c.write(slave_address_acc, measure_bit_on_command, 2);
  
    DEBUG_UART1.printf("    ACCELEROMETER DATA LOG \r\n\r\n");
    
    while (1)
    {
        if(Motion_Detect_Status)
        {
            // The following statement disables all interrupts since no other interrupts must disturb at this point 
            i2c.write(slave_address_acc, intr_source_address, 1);
            i2c.read(slave_address_acc, interrupt_source, 1);       // Reads the Interrupt Source Register
            char_to_int(interrupt_source[0]);   // Coverts intr_source(char) to int & stores in intr_source_duplicate
            
            Motion_Detect_Status = FALSE;
            Motion_Type_Detected = MOTION_TYPE_UNKNOWN;
            // USE THE FOLLOWING BLOCK TO READ THE DATA IN X-AXIS, Y-AXIS & Z-AXIS
            //---------------------------------------------------------------------------------------------------------------------------------
            if(interrupt_source_duplicate & DOUBLE_TAP_INTERRUPT)   // Check whether it is double tap (sudden jerk) interrupt
            {
                // ATTACH YOUR SUDDEN JERK EXECUTION ROUTINE HERE
                i2c.write(slave_address_acc, inactivity_interrupt_disable_command, 2);  // Disables Inactivity interrupt & enables Double Tap & Activity interrupt
                DEBUG_UART1.printf("ENTERED SUDDEN JERK CONDITION \r\n\r\n");    // To be removed
                interrupt_source_duplicate = 0x00;  // Sudden jerk also comes with activity interrupt triggered, hence this statements makes the activity check fail
                Motion_Type_Detected = MOTION_TYPE_TAP;
                Accelerometer_Interrupt_Generated = TRUE;
            }
            //---------------------------------------------------------------------------------------------------------------------------------   
            // VERIFY WHETHER THE INTERRUPT IS BECAUSE OF ACTIVITY 
 
            if(interrupt_source_duplicate & ACTIVITY_INTERRUPT)
            {
                i2c.write(slave_address_acc, activity_interrupt_disable_command, 2); // Disables Activity interrupt & enables Inactivity interrupt
                get_vehicle_speed();
                previous_speed = vehicle_speed;
                wait(5);
                get_vehicle_speed();
                current_speed = vehicle_speed;
                if((current_speed > previous_speed) && (current_speed > speed_threshold))
                {
                    Motion_Type_Detected = MOTION_TYPE_STOP_TO_START;
                    Accelerometer_Interrupt_Generated = TRUE;
                    DEBUG_UART1.printf("VEHICLE HAS STARTED (STOP TO START) \r\n");
                    // ATTACH UR STOP TO START ROUTINE HERE
                }
            }
            //---------------------------------------------------------------------------------------------------------------------------------
  
            // VERIFY WHETHER THE INTERRUPT IS BECAUSE OF INACTIVITY 
            if(interrupt_source_duplicate & INACTIVITY_INTERRUPT) 
            {
                i2c.write(slave_address_acc, inactivity_interrupt_disable_command, 2);  // Disables Inactivity interrupt & enables Activity interrupt
                get_vehicle_speed();
                if(vehicle_speed == 0)
                {
                    Motion_Type_Detected = MOTION_TYPE_START_TO_STOP;
                    Accelerometer_Interrupt_Generated = TRUE;
                    // ATTACH YOUR START TO STOP PROCESS OVERFLOW HERE
                    DEBUG_UART1.printf("VEHICLE HAS STOPPED (START TO STOP) \r\n");
                }
            }      
            wait(0.25);
            i2c.write(slave_address_acc, axis_data_start_address, 1);
            i2c.read(slave_address_acc, axis_data, 6);
                   
            x_axis = axis_data[1];  // Puts MSB data into respective axes
            y_axis = axis_data[3];
            z_axis = axis_data[5];
        }
        Thread::wait(200);  //wait for 100msec
    }
 }*/


/*

// INTERFACING ADXL345 ACCELEROMETER USING I2C 

/*
NOTE :

ACTIVITY   :  ACCELEROMETER IS ACCELERATING AND ITS VALUES ARE GREATER THAN THE ACTIVITY THRESHOLD
INACTIVITY :  ACCELEROMETER IS NOT IN ACCELERATION OR ACCELERATING VERY SLIGHTLY THAT ITS VALUES ARE BELOW THE INACTIVITY THRESHOLD  
DOUBLE TAP :  SUDDEN JERK CONDITION (IDENIFIED BY SUDDEN VARIATIONS IN THE ACCELERATION VALUES)


Due to communication speed limitations, the maximum output
data rate when using 400 kHz I2C is 800 Hz and scales linearly with
a change in the I2C communication speed

*/

/*

//----------------------------------------------------------------------------------------------------------

// CONVERTS THE CHAR DATA TO UNSIGNED INTERGER DATA

void char_to_int(char data_fetched)
{
    unsigned int shifter;
    interrupt_source_duplicate = 0x00;
    for(shifter = 0; shifter < 8; shifter++)
    {
        interrupt_source_duplicate |= (((data_fetched >> shifter) & 0x01) << shifter); // Converts char data into unsigned int
    }   
}

//----------------------------------------------------------------------------------------------------------

// LEAVE THIS ROUTINE COMMENTED (IT JUST PRINTS THE DATA IN BINARY FORMAT)

void print_data_bits(char data_fetched)
{
    unsigned int shifter;
    for(shifter = 0; shifter < 8; shifter++)
    {
        DEBUG_UART1.printf("%d",((data_fetched&0x80)>>7));
        data_fetched = data_fetched << 1;
    }
    DEBUG_UART1.printf("\r\n\r\n");       
}

//----------------------------------------------------------------------------------------------------------

void get_vehicle_speed(void)
{
    // PASS OBD COMMAND "010D<CR>" AND FETCH THE VEHICLE SPEED AT THIS POINT
}
   

//void interrupt_activity_inactivity()
//{   
    //i2c.write(slave_address_acc, all_interrupt_clear_command, 2);  
    //DEBUG_UART1.printf("    A");
  //  Motion_Detect_Status = TRUE; 
//}

//----------------------------------------------------------------------------------------------------------
 //this thread is to send lora packets periodically.
 void Accelerometer_Process_thread()//void const *args) 
 {    
    DEBUG_UART1.baud(115200);
   // inactivity.rise(interrupt_activity_inactivity); // Attach the address of interrupt_activity_inactivity function to rising edge
    
    // THE FOLLOWING GROUP OF COMMAND VARIABLES STORES THE CONFIGURATION VALUES TO BE WRITTEN TO THE ADXL345 ACCELEROMETER 
    threshold_offset_command[0] = 0x1D;                 // Threshold Tap Register address
    threshold_offset_command[1] = TAP_THRESHOLD;                   // Threshold tap Register value
    threshold_offset_command[2] = X_AXIS_OFFSET;        // Offset - X axis
    threshold_offset_command[3] = Y_AXIS_OFFSET;        // Offset - Y axis
    threshold_offset_command[4] = Z_AXIS_OFFSET;        // Offset - Z axis
    
    act_inact_time_config_command[0] = 0x21;     // DUR Register address
    act_inact_time_config_command[1] = DUR_TIME;     
    act_inact_time_config_command[2] = LATENT_TIME;     
    act_inact_time_config_command[3] = WINDOW_TIME;     
    act_inact_time_config_command[4] = ACTIVITY_THRESHOLD;       
    act_inact_time_config_command[5] = INACTIVITY_THRESHOLD;        // THRES_INACT Register 
    act_inact_time_config_command[6] = INACTIVITY_VALIDATION_TIME;  // TIME_INACT Register, making inactivity detection time = 5 secs
    act_inact_time_config_command[7] = 0x77;                        // Activity, Inactivity detection enabled for all axis
    
    interrupt_enable_command[0] = 0x2E;     // INT Enable Register address
    interrupt_enable_command[1] = 0x38;     // Enabling Double tap (sudden jerk), Activity & Inactivity Interrupts
    interrupt_enable_command[2] = 0xFF;     // Double tap (sudden jerk), Activity & inactivity interrupts are mapped to INT2 pin
     
    tap_axis_enable_command[0] = 0x2A;     // Address of the TAP_AXES Register
    tap_axis_enable_command[1] = 0x07;     // X, Y & Z axis participate in tap detection
    
    baud_rate_command[0] = 0x2C;     // Address of the BW RATE register
    baud_rate_command[1] = 0x0D;     // Increased the data rate to 800Hz, default is 0x0A indicating 100Hz
            
    data_format_command[0] = 0x31;    // Data format register address
    data_format_command[1] = 0x04;    // Making the acceleration data as left justified
    
    measure_bit_on_command[0] = 0x2D;      // Post the Register address of the slave (Have to write this into slave)
    measure_bit_on_command[1] = 0x08;      // Turn ON the Measure Bit
    
    i2c.write(slave_address_acc, threshold_offset_command, 5);
    i2c.write(slave_address_acc, act_inact_time_config_command, 8);
    i2c.write(slave_address_acc, interrupt_enable_command, 3);
    i2c.write(slave_address_acc, tap_axis_enable_command, 2);
    i2c.write(slave_address_acc, baud_rate_command, 2);
    i2c.write(slave_address_acc, data_format_command, 2);
    i2c.write(slave_address_acc, measure_bit_on_command, 2);
  
    DEBUG_UART1.printf("    ACCELEROMETER DATA LOG \r\n\r\n");
    
    while (1)
    {
        if(Motion_Detect_Status)
        {
            // The following statement disables all interrupts since no other interrupts must disturb at this point 
            i2c.write(slave_address_acc, intr_source_address, 1);
            i2c.read(slave_address_acc, interrupt_source, 1);       // Reads the Interrupt Source Register
            char_to_int(interrupt_source[0]);   // Coverts intr_source(char) to int & stores in intr_source_duplicate
            
            Motion_Detect_Status = FALSE;
            Motion_Type_Detected = MOTION_TYPE_UNKNOWN;
            DEBUG_UART1.printf("Motion detected");
            DEBUG_UART1.putc(interrupt_source_duplicate);
            // USE THE FOLLOWING BLOCK TO READ THE DATA IN X-AXIS, Y-AXIS & Z-AXIS
            //---------------------------------------------------------------------------------------------------------------------------------
            if(interrupt_source_duplicate & DOUBLE_TAP_INTERRUPT)   // Check whether it is double tap (sudden jerk) interrupt
            {
                // ATTACH YOUR SUDDEN JERK EXECUTION ROUTINE HERE
                i2c.write(slave_address_acc, inactivity_interrupt_disable_command, 2);  // Disables Inactivity interrupt & enables Double Tap & Activity interrupt
                DEBUG_UART1.printf("ENTERED SUDDEN JERK CONDITION \r\n\r\n");    // To be removed
                interrupt_source_duplicate = 0x00;  // Sudden jerk also comes with activity interrupt triggered, hence this statements makes the activity check fail
                Motion_Type_Detected = MOTION_TYPE_TAP;
                Accelerometer_Interrupt_Generated = TRUE;
            }
            //---------------------------------------------------------------------------------------------------------------------------------   
            / VERIFY WHETHER THE INTERRUPT IS BECAUSE OF ACTIVITY 
 
            if(interrupt_source_duplicate & ACTIVITY_INTERRUPT)
            {
                i2c.write(slave_address_acc, activity_interrupt_disable_command, 2); // Disables Activity interrupt & enables Inactivity interrupt
                get_vehicle_speed();
                previous_speed = vehicle_speed;
                wait(5);
                get_vehicle_speed();
                current_speed = vehicle_speed;
                if((current_speed > previous_speed) && (current_speed > speed_threshold))
                {
                    Motion_Type_Detected = MOTION_TYPE_STOP_TO_START;
                    Accelerometer_Interrupt_Generated = TRUE;
                    DEBUG_UART1.printf("VEHICLE HAS STARTED (STOP TO START) \r\n");
                    // ATTACH UR STOP TO START ROUTINE HERE
                }
            }
            //---------------------------------------------------------------------------------------------------------------------------------

            // VERIFY WHETHER THE INTERRUPT IS BECAUSE OF INACTIVITY 
            if(interrupt_source_duplicate & INACTIVITY_INTERRUPT) 
            {
                i2c.write(slave_address_acc, inactivity_interrupt_disable_command, 2);  // Disables Inactivity interrupt & enables Activity interrupt
                get_vehicle_speed();
                if(vehicle_speed == 0)
                {
                    Motion_Type_Detected = MOTION_TYPE_START_TO_STOP;
                    Accelerometer_Interrupt_Generated = TRUE;
                    // ATTACH YOUR START TO STOP PROCESS OVERFLOW HERE
                    DEBUG_UART1.printf("VEHICLE HAS STOPPED (START TO STOP) \r\n");
                }
            }      
            wait(0.25);
            i2c.write(slave_address_acc, axis_data_start_address, 1);
            i2c.read(slave_address_acc, axis_data, 6);
                   
            x_axis = axis_data[1];  // Puts MSB data into respective axes
            y_axis = axis_data[3];
            z_axis = axis_data[5];
        }
        Thread::wait(200);  //wait for 100msec
    }
 }


*/