SensorInterface.cpp

/*Joseph Picard, Brandeis University; Ashton-Graybiel Spatial Orientation Lab

 Purpose: General purpose accelerometer/gyroscope to tactor effect controller.

 Email: jcpicard32@gmail.com

 Rights: Copyright (C) 2019 Joseph Picard
 License is GPL-3.0, included in License.txt of this project.

Circuit:
MPU6000 sensor attached to pins 10 - 13:
CSB: pin 10
MOSI: pin 11
MISO: pin 12
SCK: pin 13 2019/08/09*/

//this should work on all boards, so there is no preprocessor directive here

//includes the libraries of code necessary to make this one work
#include <SensorInterface.h>

//Creates a new SensorInterface object
SensorInterface::SensorInterface() {
}

//Initializes the class, can't always be done at same time as constructor
void SensorInterface::begin() {

 //pins used for the connection with the sensor
 chipSelectPin = 10;
 //the other you need are controlled by the SPI library):
 //dataReadyPin = 6;
	
	pinMode(chipSelectPin, OUTPUT);
 digitalWrite(chipSelectPin, HIGH);
	MPU6000_Init();
}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getXAccelerometerCounts(void) {
 int tempData_HI,tempData_LO;
 //Read the data
 tempData_HI = readRegister(ACCEL_XOUT_H);
 tempData_LO = readRegister(ACCEL_XOUT_L );
 return ((tempData_HI << 8)+ tempData_LO) ;

}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getYAccelerometerCounts(void) {
 int tempData_HI,tempData_LO;
 tempData_HI = readRegister(ACCEL_YOUT_H);
 tempData_LO = readRegister(ACCEL_YOUT_L );
 return ((tempData_HI << 8) + tempData_LO);

}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getZAccelerometerCounts(void) {
 int tempData_HI,tempData_LO;
 tempData_HI = readRegister(ACCEL_ZOUT_H );
 tempData_LO = readRegister(ACCEL_ZOUT_L );
 return ((tempData_HI << 8) + tempData_LO);

}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getXGyroCounts(void) {
 int tempData_HI,tempData_LO;
 tempData_HI = readRegister(GYRO_XOUT_H );
 tempData_LO = readRegister(GYRO_XOUT_L );
 return ((tempData_HI << 8) + tempData_LO);

}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getYGyroCounts(void) {
 int tempData_HI,tempData_LO;
 tempData_HI = readRegister(GYRO_YOUT_H);
 tempData_LO = readRegister(GYRO_YOUT_L );
 return ((tempData_HI << 8) + tempData_LO);

}

//TODO: EXPLAIN WHAT METHOD DOES
int SensorInterface::getZGyroCounts(void) {
 int tempData_HI,tempData_LO;
 tempData_HI = readRegister(GYRO_ZOUT_H);
 tempData_LO = readRegister(GYRO_ZOUT_L);
 return ((tempData_HI << 8) + tempData_LO);

}
unsigned int SensorInterface::getTemperature(void){
 int tempData_HI,tempData_LO;

 tempData_HI = readRegister(TEMP_OUT_H + READ_FLAG);
 tempData_LO = readRegister(TEMP_OUT_L + READ_FLAG);

 return ((tempData_HI << 8) + tempData_LO);
}

// MPU6000 Initialization and configuration
void SensorInterface::MPU6000_Init(void) {
 // MPU6000 chip select setup
 // pinMode(MPU6000_CHIP_SELECT_PIN, OUTPUT);
 // writeRegister(MPU6000_CHIP_SELECT_PIN, HIGH);
 // SPI initialization
 SPI.begin();
 SPI.setClockDivider(SPI_CLOCK_DIV16); // SPI at 1Mhz (on 16Mhz clock)
 delay(10);
 // Chip reset
 writeRegister(MPUREG_PWR_MGMT_1, BIT_H_RESET);
 delay(100);
 // Wake up device and select GyroZ clock (better performance)
 writeRegister(MPUREG_PWR_MGMT_1, MPU_CLK_SEL_PLLGYROZ);
 delay(1);
 // Disable I2C bus (recommended on datasheet)
 writeRegister(MPUREG_USER_CTRL, BIT_I2C_IF_DIS);
 delay(1);
 // SAMPLE RATE
 //MPU6000_SPI_write(MPUREG_SMPLRT_DIV,0x04); // Sample rate = 200Hz Fsample= 1Khz/(4+1) = 200Hz
 writeRegister(MPUREG_SMPLRT_DIV,19); // Sample rate = 50Hz Fsample= 1Khz/(19+1) = 50Hz
 delay(1);
 // FS & DLPF FS=2000º/s, DLPF = 20Hz (low pass filter)
 writeRegister(MPUREG_CONFIG, BITS_DLPF_CFG_20HZ);
 delay(1);
 writeRegister(MPUREG_GYRO_CONFIG,BITS_FS_2000DPS); // Gyro scale 2000º/s
 delay(1);
 writeRegister(MPUREG_ACCEL_CONFIG,0x08); // Accel scale 4g (4096LSB/g)
 delay(1);
 // INT CFG => Interrupt on Data Ready
 //writeRegister(MPUREG_INT_ENABLE,BIT_RAW_RDY_EN); // INT: Raw data ready
 //delay(1);
 //writeRegister(MPUREG_INT_PIN_CFG,BIT_INT_ANYRD_2CLEAR); // INT: Clear on any read
 //delay(1);
 // Oscillator set
 writeRegister(MPUREG_PWR_MGMT_1,MPU_CLK_SEL_PLLGYROZ);
 delay(1);
 // MPU_INT is connected to INT 0. Enable interrupt on INT0
 // attachInterrupt(0,MPU6000_data_int,RISING);

}


//Read from or write to register
unsigned int SensorInterface::readRegister(byte thisRegister) {
 unsigned int result = 0; // result to return
 byte addr = thisRegister + 0x80;
 // Serial.print(thisRegister, BIN);
 // byte dataToSend = thisRegister ;
 //Serial.println(thisRegister, BIN);
 // take the chip select low to select the device:
 digitalWrite(chipSelectPin, LOW);
 // send the device the register you want to read:
 SPI.transfer(addr);
 // send a value of 0 to read the first byte returned:
 result = SPI.transfer(0x00);
 // take the chip select high to de-select:
 digitalWrite(chipSelectPin, HIGH);
 // return the result:
 return(result);

}

//Sends a write command
void SensorInterface::writeRegister(byte thisRegister, byte thisValue) {
 thisRegister = thisRegister ;
 // now combine the register address and the command into one byte:
 byte dataToSend = thisRegister;
 // take the chip select low to select the device:
 digitalWrite(chipSelectPin, LOW);
 SPI.transfer(dataToSend); //Send register location
 SPI.transfer(thisValue); //Send value to record into register
 // take the chip select high to de-select:
 digitalWrite(chipSelectPin, HIGH);

}