INF2004_Project/frtos/magnetometer/magnetometer_init.h

125 lines
3.2 KiB
C

/**
* @file magnetometer_init.h
* @author Woon Jun Wei
* @brief Initialise the magnetometer sensor and
* calculate the direction of the car
*
* @details This file contains the function prototypes for the
* magnetometer sensor and the function to calculate
* the direction of the car based on the magnetometer sensor data
*/
#ifndef MAGNETOMETER_INIT_H
#define MAGNETOMETER_INIT_H
#include <stdio.h>
#include <math.h>
#include "pico/stdlib.h"
#include "hardware/i2c.h"
#include "pico/binary_info.h"
#include "FreeRTOS.h"
#include "task.h"
#include "message_buffer.h"
#include "semphr.h"
#include "magnetometer_config.h"
#include "LSM303DLHC_register.h"
// Semaphores
SemaphoreHandle_t g_direction_sem = NULL;
direction_t g_direction = {
.roll = 0,
.pitch = 0,
.yaw = 0,
.orientation = NORTH,
.roll_angle = LEFT,
.pitch_angle = UP
};
/**
* @brief Initialise the LSM303DLHC sensor (Accelerometer and Magnetometer)
* @details
* Accelerometer - Normal power mode, all axes enabled, 10 Hz,
* Full Scale +-2g, continuous update
*
* Magnetometer - Continuous-conversion mode, Gain = +/- 1.3,
* Enable temperature sensor, 220 Hz
*
* @return None
*/
static void
LSM303DLHC_init() {
/**
* Accelerometer Setup
*/
// 0x20 = CTRL_REG1_A
// Normal power mode, all axes enabled, 10 Hz
uint8_t buf[2] = {LSM303_CTRL_REG1_A, 0x27};
i2c_write_blocking(i2c_default, ACCEL_ADDR, buf, 2, false);
// Reboot memory content (0x40 = CTRL_REG4_A)
// Full Scale +-2g, continuous update (0x00 = 0b0000 0000)
buf[0] = LSM303_CTRL_REG4_A;
buf[1] = 0x00;
i2c_write_blocking(i2c_default, ACCEL_ADDR, buf, 2, false);
/**
* Magnetometer Setup
*/
// MR_REG_M (0x02) - Continuous-conversion mode (0x00 -> 00000000)
buf[0] = LSM303_MR_REG_M;
buf[1] = 0x00;
i2c_write_blocking(i2c_default, MAG_ADDR, buf, 2, false);
// CRB_REG_M (0x01) - Gain = +/- 1.3 (0x20 -> 00100000)
buf[0] = LSM303_CRB_REG_M;
buf[1] = 0x20;
i2c_write_blocking(i2c_default, MAG_ADDR, buf, 2, false);
// CRA_REG_M (0x00), 0x9C = 0b1001 1100
// Enable temperature sensor (0x80 -> 1000 0000)
// 220 Hz (0x1C -> 0001 1100)
buf[0] = LSM303_CRA_REG_M;
buf[1] = 0x9C;
i2c_write_blocking(i2c_default, MAG_ADDR, buf, 2, false);
}
/**
* @brief Initialise the Magnetometer Sensor
* @details Initialise the I2C Port, SDA and SCL Pins, and the LSM303DLHC Sensor
*/
void
magnetometer_init()
{
i2c_init(I2C_PORT, 400 * 1000);
gpio_set_function(I2C_SDA, GPIO_FUNC_I2C);
gpio_set_function(I2C_SCL, GPIO_FUNC_I2C);
gpio_pull_up(I2C_SDA);
gpio_pull_up(I2C_SCL);
LSM303DLHC_init();
// Semaphore
g_direction_sem = xSemaphoreCreateBinary();
}
/**
* @brief Timer Interrupt Handler To calculate the direction of the car
* @param repeatingTimer The timer handler
* @return True (To keep the timer running)
*/
bool
h_direction_timer_handler(repeating_timer_t *repeatingTimer) {
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
xSemaphoreGiveFromISR(g_direction_sem,
&xHigherPriorityTaskWoken);
portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
return true;
}
#endif