first commit
This commit is contained in:
478
libraries/Adafruit_BMP085_Unified/Adafruit_BMP085_U.cpp
Normal file
478
libraries/Adafruit_BMP085_Unified/Adafruit_BMP085_U.cpp
Normal file
@@ -0,0 +1,478 @@
|
||||
/*!
|
||||
* @file Adafruit_BMP085_U.cpp
|
||||
*
|
||||
* @mainpage Adafruit BMP085 Pressure Sensor
|
||||
*
|
||||
* @section intro_sec Introduction
|
||||
*
|
||||
* This is a library for the BMP085 pressure sensor
|
||||
*
|
||||
* Designed specifically to work with the Adafruit BMP085 or BMP180 Breakout
|
||||
* ----> http://www.adafruit.com/products/391
|
||||
* ----> http://www.adafruit.com/products/1603
|
||||
*
|
||||
* These displays use I2C to communicate, 2 pins are required to interface.
|
||||
*
|
||||
* Adafruit invests time and resources providing this open source code,
|
||||
* please support Adafruit andopen-source hardware by purchasing products
|
||||
* from Adafruit!
|
||||
*
|
||||
* @section author Author
|
||||
*
|
||||
* Written by Kevin Townsend for Adafruit Industries.
|
||||
*
|
||||
* @section license License
|
||||
* BSD license, all text above must be included in any redistribution
|
||||
*/
|
||||
|
||||
#if ARDUINO >= 100
|
||||
#include "Arduino.h"
|
||||
#else
|
||||
#include "WProgram.h"
|
||||
#endif
|
||||
|
||||
#ifdef __AVR_ATtiny85__
|
||||
#include "TinyWireM.h"
|
||||
#define Wire TinyWireM
|
||||
#else
|
||||
#include <Wire.h>
|
||||
#endif
|
||||
|
||||
#include <limits.h>
|
||||
#include <math.h>
|
||||
|
||||
#include "Adafruit_BMP085_U.h"
|
||||
|
||||
static bmp085_calib_data
|
||||
_bmp085_coeffs; // Last read accelerometer data will be available here
|
||||
static uint8_t _bmp085Mode;
|
||||
|
||||
#define BMP085_USE_DATASHEET_VALS \
|
||||
(0) //!< Set to 1 for sanity check, when true, will use values from datasheet
|
||||
|
||||
/***************************************************************************
|
||||
PRIVATE FUNCTIONS
|
||||
***************************************************************************/
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Writes an 8 bit value over I2C
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void writeCommand(byte reg, byte value) {
|
||||
Wire.beginTransmission((uint8_t)BMP085_ADDRESS);
|
||||
#if ARDUINO >= 100
|
||||
Wire.write((uint8_t)reg);
|
||||
Wire.write((uint8_t)value);
|
||||
#else
|
||||
Wire.send(reg);
|
||||
Wire.send(value);
|
||||
#endif
|
||||
Wire.endTransmission();
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads an 8 bit value over I2C
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void read8(byte reg, uint8_t *value) {
|
||||
Wire.beginTransmission((uint8_t)BMP085_ADDRESS);
|
||||
#if ARDUINO >= 100
|
||||
Wire.write((uint8_t)reg);
|
||||
#else
|
||||
Wire.send(reg);
|
||||
#endif
|
||||
Wire.endTransmission();
|
||||
Wire.requestFrom((uint8_t)BMP085_ADDRESS, (byte)1);
|
||||
#if ARDUINO >= 100
|
||||
*value = Wire.read();
|
||||
#else
|
||||
*value = Wire.receive();
|
||||
#endif
|
||||
Wire.endTransmission();
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads a 16 bit value over I2C
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void read16(byte reg, uint16_t *value) {
|
||||
Wire.beginTransmission((uint8_t)BMP085_ADDRESS);
|
||||
#if ARDUINO >= 100
|
||||
Wire.write((uint8_t)reg);
|
||||
#else
|
||||
Wire.send(reg);
|
||||
#endif
|
||||
Wire.endTransmission();
|
||||
Wire.requestFrom((uint8_t)BMP085_ADDRESS, (byte)2);
|
||||
#if ARDUINO >= 100
|
||||
*value = (Wire.read() << 8) | Wire.read();
|
||||
#else
|
||||
*value = (Wire.receive() << 8) | Wire.receive();
|
||||
#endif
|
||||
Wire.endTransmission();
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads a signed 16 bit value over I2C
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void readS16(byte reg, int16_t *value) {
|
||||
uint16_t i;
|
||||
read16(reg, &i);
|
||||
*value = (int16_t)i;
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads the factory-set coefficients
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void readCoefficients(void) {
|
||||
#if BMP085_USE_DATASHEET_VALS
|
||||
_bmp085_coeffs.ac1 = 408;
|
||||
_bmp085_coeffs.ac2 = -72;
|
||||
_bmp085_coeffs.ac3 = -14383;
|
||||
_bmp085_coeffs.ac4 = 32741;
|
||||
_bmp085_coeffs.ac5 = 32757;
|
||||
_bmp085_coeffs.ac6 = 23153;
|
||||
_bmp085_coeffs.b1 = 6190;
|
||||
_bmp085_coeffs.b2 = 4;
|
||||
_bmp085_coeffs.mb = -32768;
|
||||
_bmp085_coeffs.mc = -8711;
|
||||
_bmp085_coeffs.md = 2868;
|
||||
_bmp085Mode = 0;
|
||||
#else
|
||||
readS16(BMP085_REGISTER_CAL_AC1, &_bmp085_coeffs.ac1);
|
||||
readS16(BMP085_REGISTER_CAL_AC2, &_bmp085_coeffs.ac2);
|
||||
readS16(BMP085_REGISTER_CAL_AC3, &_bmp085_coeffs.ac3);
|
||||
read16(BMP085_REGISTER_CAL_AC4, &_bmp085_coeffs.ac4);
|
||||
read16(BMP085_REGISTER_CAL_AC5, &_bmp085_coeffs.ac5);
|
||||
read16(BMP085_REGISTER_CAL_AC6, &_bmp085_coeffs.ac6);
|
||||
readS16(BMP085_REGISTER_CAL_B1, &_bmp085_coeffs.b1);
|
||||
readS16(BMP085_REGISTER_CAL_B2, &_bmp085_coeffs.b2);
|
||||
readS16(BMP085_REGISTER_CAL_MB, &_bmp085_coeffs.mb);
|
||||
readS16(BMP085_REGISTER_CAL_MC, &_bmp085_coeffs.mc);
|
||||
readS16(BMP085_REGISTER_CAL_MD, &_bmp085_coeffs.md);
|
||||
#endif
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void readRawTemperature(int32_t *temperature) {
|
||||
#if BMP085_USE_DATASHEET_VALS
|
||||
*temperature = 27898;
|
||||
#else
|
||||
uint16_t t;
|
||||
writeCommand(BMP085_REGISTER_CONTROL, BMP085_REGISTER_READTEMPCMD);
|
||||
delay(5);
|
||||
read16(BMP085_REGISTER_TEMPDATA, &t);
|
||||
*temperature = t;
|
||||
#endif
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
|
||||
*/
|
||||
/**************************************************************************/
|
||||
static void readRawPressure(int32_t *pressure) {
|
||||
#if BMP085_USE_DATASHEET_VALS
|
||||
*pressure = 23843;
|
||||
#else
|
||||
uint8_t p8;
|
||||
uint16_t p16;
|
||||
int32_t p32;
|
||||
|
||||
writeCommand(BMP085_REGISTER_CONTROL,
|
||||
BMP085_REGISTER_READPRESSURECMD + (_bmp085Mode << 6));
|
||||
switch (_bmp085Mode) {
|
||||
case BMP085_MODE_ULTRALOWPOWER:
|
||||
delay(5);
|
||||
break;
|
||||
case BMP085_MODE_STANDARD:
|
||||
delay(8);
|
||||
break;
|
||||
case BMP085_MODE_HIGHRES:
|
||||
delay(14);
|
||||
break;
|
||||
case BMP085_MODE_ULTRAHIGHRES:
|
||||
default:
|
||||
delay(26);
|
||||
break;
|
||||
}
|
||||
|
||||
read16(BMP085_REGISTER_PRESSUREDATA, &p16);
|
||||
p32 = (uint32_t)p16 << 8;
|
||||
read8(BMP085_REGISTER_PRESSUREDATA + 2, &p8);
|
||||
p32 += p8;
|
||||
p32 >>= (8 - _bmp085Mode);
|
||||
|
||||
*pressure = p32;
|
||||
#endif
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Compute B5 coefficient used in temperature & pressure calcs.
|
||||
*/
|
||||
/**************************************************************************/
|
||||
int32_t Adafruit_BMP085_Unified::computeB5(int32_t ut) {
|
||||
int32_t X1 =
|
||||
(ut - (int32_t)_bmp085_coeffs.ac6) * ((int32_t)_bmp085_coeffs.ac5) >> 15;
|
||||
int32_t X2 =
|
||||
((int32_t)_bmp085_coeffs.mc << 11) / (X1 + (int32_t)_bmp085_coeffs.md);
|
||||
return X1 + X2;
|
||||
}
|
||||
|
||||
/***************************************************************************
|
||||
CONSTRUCTOR
|
||||
***************************************************************************/
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Instantiates a new Adafruit_BMP085_Unified class
|
||||
*/
|
||||
/**************************************************************************/
|
||||
Adafruit_BMP085_Unified::Adafruit_BMP085_Unified(int32_t sensorID) {
|
||||
_sensorID = sensorID;
|
||||
}
|
||||
|
||||
/***************************************************************************
|
||||
PUBLIC FUNCTIONS
|
||||
***************************************************************************/
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Setups the HW
|
||||
*/
|
||||
/**************************************************************************/
|
||||
bool Adafruit_BMP085_Unified::begin(bmp085_mode_t mode) {
|
||||
// Enable I2C
|
||||
Wire.begin();
|
||||
|
||||
/* Mode boundary check */
|
||||
if ((mode > BMP085_MODE_ULTRAHIGHRES) || (mode < 0)) {
|
||||
mode = BMP085_MODE_ULTRAHIGHRES;
|
||||
}
|
||||
|
||||
/* Make sure we have the right device */
|
||||
uint8_t id;
|
||||
read8(BMP085_REGISTER_CHIPID, &id);
|
||||
if (id != 0x55) {
|
||||
return false;
|
||||
}
|
||||
|
||||
/* Set the mode indicator */
|
||||
_bmp085Mode = mode;
|
||||
|
||||
/* Coefficients need to be read once */
|
||||
readCoefficients();
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Gets the compensated pressure level in kPa
|
||||
*/
|
||||
/**************************************************************************/
|
||||
void Adafruit_BMP085_Unified::getPressure(float *pressure) {
|
||||
int32_t ut = 0, up = 0, compp = 0;
|
||||
int32_t x1, x2, b5, b6, x3, b3, p;
|
||||
uint32_t b4, b7;
|
||||
|
||||
/* Get the raw pressure and temperature values */
|
||||
readRawTemperature(&ut);
|
||||
readRawPressure(&up);
|
||||
|
||||
/* Temperature compensation */
|
||||
b5 = computeB5(ut);
|
||||
|
||||
/* Pressure compensation */
|
||||
b6 = b5 - 4000;
|
||||
x1 = (_bmp085_coeffs.b2 * ((b6 * b6) >> 12)) >> 11;
|
||||
x2 = (_bmp085_coeffs.ac2 * b6) >> 11;
|
||||
x3 = x1 + x2;
|
||||
b3 = (((((int32_t)_bmp085_coeffs.ac1) * 4 + x3) << _bmp085Mode) + 2) >> 2;
|
||||
x1 = (_bmp085_coeffs.ac3 * b6) >> 13;
|
||||
x2 = (_bmp085_coeffs.b1 * ((b6 * b6) >> 12)) >> 16;
|
||||
x3 = ((x1 + x2) + 2) >> 2;
|
||||
b4 = (_bmp085_coeffs.ac4 * (uint32_t)(x3 + 32768)) >> 15;
|
||||
b7 = ((uint32_t)(up - b3) * (50000 >> _bmp085Mode));
|
||||
|
||||
if (b7 < 0x80000000) {
|
||||
p = (b7 << 1) / b4;
|
||||
} else {
|
||||
p = (b7 / b4) << 1;
|
||||
}
|
||||
|
||||
x1 = (p >> 8) * (p >> 8);
|
||||
x1 = (x1 * 3038) >> 16;
|
||||
x2 = (-7357 * p) >> 16;
|
||||
compp = p + ((x1 + x2 + 3791) >> 4);
|
||||
|
||||
/* Assign compensated pressure value */
|
||||
*pressure = compp;
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads the temperatures in degrees Celsius
|
||||
*/
|
||||
/**************************************************************************/
|
||||
void Adafruit_BMP085_Unified::getTemperature(float *temp) {
|
||||
int32_t UT, B5; // following ds convention
|
||||
float t;
|
||||
|
||||
readRawTemperature(&UT);
|
||||
|
||||
#if BMP085_USE_DATASHEET_VALS
|
||||
// use datasheet numbers!
|
||||
UT = 27898;
|
||||
_bmp085_coeffs.ac6 = 23153;
|
||||
_bmp085_coeffs.ac5 = 32757;
|
||||
_bmp085_coeffs.mc = -8711;
|
||||
_bmp085_coeffs.md = 2868;
|
||||
#endif
|
||||
|
||||
B5 = computeB5(UT);
|
||||
t = (B5 + 8) >> 4;
|
||||
t /= 10;
|
||||
|
||||
*temp = t;
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
Calculates the altitude (in meters) from the specified atmospheric
|
||||
pressure (in hPa), and sea-level pressure (in hPa).
|
||||
|
||||
@param seaLevel Sea-level pressure in hPa
|
||||
@param atmospheric Atmospheric pressure in hPa
|
||||
*/
|
||||
/**************************************************************************/
|
||||
float Adafruit_BMP085_Unified::pressureToAltitude(float seaLevel,
|
||||
float atmospheric) {
|
||||
// Equation taken from BMP180 datasheet (page 16):
|
||||
// http://www.adafruit.com/datasheets/BST-BMP180-DS000-09.pdf
|
||||
|
||||
// Note that using the equation from wikipedia can give bad results
|
||||
// at high altitude. See this thread for more information:
|
||||
// http://forums.adafruit.com/viewtopic.php?f=22&t=58064
|
||||
|
||||
return 44330.0 * (1.0 - pow(atmospheric / seaLevel, 0.1903));
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
Calculates the altitude (in meters) from the specified atmospheric
|
||||
pressure (in hPa), and sea-level pressure (in hPa). Note that this
|
||||
function just calls the overload of pressureToAltitude which takes
|
||||
seaLevel and atmospheric pressure--temperature is ignored. The original
|
||||
implementation of this function was based on calculations from Wikipedia
|
||||
which are not accurate at higher altitudes. To keep compatibility with
|
||||
old code this function remains with the same interface, but it calls the
|
||||
more accurate calculation.
|
||||
|
||||
@param seaLevel Sea-level pressure in hPa
|
||||
@param atmospheric Atmospheric pressure in hPa
|
||||
@param temp Temperature in degrees Celsius
|
||||
*/
|
||||
/**************************************************************************/
|
||||
float Adafruit_BMP085_Unified::pressureToAltitude(float seaLevel,
|
||||
float atmospheric,
|
||||
float temp) {
|
||||
return pressureToAltitude(seaLevel, atmospheric);
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
Calculates the pressure at sea level (in hPa) from the specified altitude
|
||||
(in meters), and atmospheric pressure (in hPa).
|
||||
|
||||
@param altitude Altitude in meters
|
||||
@param atmospheric Atmospheric pressure in hPa
|
||||
*/
|
||||
/**************************************************************************/
|
||||
float Adafruit_BMP085_Unified::seaLevelForAltitude(float altitude,
|
||||
float atmospheric) {
|
||||
// Equation taken from BMP180 datasheet (page 17):
|
||||
// http://www.adafruit.com/datasheets/BST-BMP180-DS000-09.pdf
|
||||
|
||||
// Note that using the equation from wikipedia can give bad results
|
||||
// at high altitude. See this thread for more information:
|
||||
// http://forums.adafruit.com/viewtopic.php?f=22&t=58064
|
||||
|
||||
return atmospheric / pow(1.0 - (altitude / 44330.0), 5.255);
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
Calculates the pressure at sea level (in hPa) from the specified altitude
|
||||
(in meters), and atmospheric pressure (in hPa). Note that this
|
||||
function just calls the overload of seaLevelForAltitude which takes
|
||||
altitude and atmospheric pressure--temperature is ignored. The original
|
||||
implementation of this function was based on calculations from Wikipedia
|
||||
which are not accurate at higher altitudes. To keep compatibility with
|
||||
old code this function remains with the same interface, but it calls the
|
||||
more accurate calculation.
|
||||
|
||||
@param altitude Altitude in meters
|
||||
@param atmospheric Atmospheric pressure in hPa
|
||||
@param temp Temperature in degrees Celsius
|
||||
*/
|
||||
/**************************************************************************/
|
||||
float Adafruit_BMP085_Unified::seaLevelForAltitude(float altitude,
|
||||
float atmospheric,
|
||||
float temp) {
|
||||
return seaLevelForAltitude(altitude, atmospheric);
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Provides the sensor_t data for this sensor
|
||||
*/
|
||||
/**************************************************************************/
|
||||
void Adafruit_BMP085_Unified::getSensor(sensor_t *sensor) {
|
||||
/* Clear the sensor_t object */
|
||||
memset(sensor, 0, sizeof(sensor_t));
|
||||
|
||||
/* Insert the sensor name in the fixed length char array */
|
||||
strncpy(sensor->name, "BMP085", sizeof(sensor->name) - 1);
|
||||
sensor->name[sizeof(sensor->name) - 1] = 0;
|
||||
sensor->version = 1;
|
||||
sensor->sensor_id = _sensorID;
|
||||
sensor->type = SENSOR_TYPE_PRESSURE;
|
||||
sensor->min_delay = 0;
|
||||
sensor->max_value = 1100.0F; // 300..1100 hPa
|
||||
sensor->min_value = 300.0F;
|
||||
sensor->resolution = 0.01F; // Datasheet states 0.01 hPa resolution
|
||||
}
|
||||
|
||||
/**************************************************************************/
|
||||
/*!
|
||||
@brief Reads the sensor and returns the data as a sensors_event_t
|
||||
*/
|
||||
/**************************************************************************/
|
||||
bool Adafruit_BMP085_Unified::getEvent(sensors_event_t *event) {
|
||||
float pressure_kPa;
|
||||
|
||||
/* Clear the event */
|
||||
memset(event, 0, sizeof(sensors_event_t));
|
||||
|
||||
event->version = sizeof(sensors_event_t);
|
||||
event->sensor_id = _sensorID;
|
||||
event->type = SENSOR_TYPE_PRESSURE;
|
||||
event->timestamp = 0;
|
||||
getPressure(&pressure_kPa);
|
||||
event->pressure = pressure_kPa / 100.0F;
|
||||
|
||||
return true;
|
||||
}
|
||||
Reference in New Issue
Block a user