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Renamed STATUS to MPLSTATUS because of incompatibility with ... #6

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43 changes: 21 additions & 22 deletions src/SparkFunMPL3115A2.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -6,15 +6,15 @@
License: This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).

This library allows an Arduino to read from the MPL3115A2 low-cost high-precision pressure sensor.

If you have feature suggestions or need support please use the github support page: https://github.com/sparkfun/MPL3115A2_Breakout

Hardware Setup: The MPL3115A2 lives on the I2C bus. Attach the SDA pin to A4, SCL to A5. Use inline 10k resistors
if you have a 5V board. If you are using the SparkFun breakout board you *do not* need 4.7k pull-up resistors
if you have a 5V board. If you are using the SparkFun breakout board you *do not* need 4.7k pull-up resistors
on the bus (they are built-in).

Link to the breakout board product:

Software:
.begin() Gets sensor on the I2C bus.
.readAltitude() Returns float with meters above sealevel. Ex: 1638.94
Expand All @@ -28,9 +28,9 @@
.setModeActive() Start taking measurements!
.setOversampleRate(byte) Sets the # of samples from 1 to 128. See datasheet.
.enableEventFlags() Sets the fundamental event flags. Required during setup.

Updated by PaulZC: October 19th, 2019

*/

#include <Wire.h>
Expand Down Expand Up @@ -61,7 +61,7 @@ float MPL3115A2::readAltitude()

//Wait for PDR bit, indicates we have new pressure data
int counter = 0;
while( (IIC_Read(STATUS) & (1<<1)) == 0)
while( (IIC_Read(MPLSTATUS) & (1<<1)) == 0)
{
if(++counter > 600) return(-999); //Error out after max of 512ms for a read
delay(1);
Expand All @@ -82,8 +82,8 @@ float MPL3115A2::readAltitude()

// The least significant bytes l_altitude and l_temp are 4-bit,
// fractional values, so you must cast the calulation in (float),
// shift the value over 4 spots to the right and divide by 16 (since
// there are 16 values in 4-bits).
// shift the value over 4 spots to the right and divide by 16 (since
// there are 16 values in 4-bits).
float tempcsb = (lsb>>4)/16.0;

float altitude = (float)( (msb << 8) | csb) + tempcsb;
Expand All @@ -103,11 +103,11 @@ float MPL3115A2::readAltitudeFt()
float MPL3115A2::readPressure()
{
//Check PDR bit, if it's not set then toggle OST
if(IIC_Read(STATUS) & (1<<2) == 0) toggleOneShot(); //Toggle the OST bit causing the sensor to immediately take another reading
if(IIC_Read(MPLSTATUS) & (1<<2) == 0) toggleOneShot(); //Toggle the OST bit causing the sensor to immediately take another reading

//Wait for PDR bit, indicates we have new pressure data
int counter = 0;
while(IIC_Read(STATUS) & (1<<2) == 0)
while(IIC_Read(MPLSTATUS) & (1<<2) == 0)
{
if(++counter > 600) return(-999); //Error out after max of 512ms for a read
delay(1);
Expand All @@ -125,7 +125,7 @@ float MPL3115A2::readPressure()
msb = _i2cPort->read();
csb = _i2cPort->read();
lsb = _i2cPort->read();

toggleOneShot(); //Toggle the OST bit causing the sensor to immediately take another reading

// Pressure comes back as a left shifted 20 bit number
Expand All @@ -143,11 +143,11 @@ float MPL3115A2::readPressure()

float MPL3115A2::readTemp()
{
if(IIC_Read(STATUS) & (1<<1) == 0) toggleOneShot(); //Toggle the OST bit causing the sensor to immediately take another reading
if(IIC_Read(MPLSTATUS) & (1<<1) == 0) toggleOneShot(); //Toggle the OST bit causing the sensor to immediately take another reading

//Wait for TDR bit, indicates we have new temp data
int counter = 0;
while( (IIC_Read(STATUS) & (1<<1)) == 0)
while( (IIC_Read(MPLSTATUS) & (1<<1)) == 0)
{
if(++counter > 600) return(-999); //Error out after max of 512ms for a read
delay(1);
Expand Down Expand Up @@ -176,20 +176,20 @@ float MPL3115A2::readTemp()
{
foo = ~((msb << 8) + lsb) + 1; //2’s complement
msb = foo >> 8;
lsb = foo & 0x00F0;
lsb = foo & 0x00F0;
negSign = true;
}

// The least significant bytes l_altitude and l_temp are 4-bit,
// fractional values, so you must cast the calulation in (float),
// shift the value over 4 spots to the right and divide by 16 (since
// there are 16 values in 4-bits).
// shift the value over 4 spots to the right and divide by 16 (since
// there are 16 values in 4-bits).
float templsb = (lsb>>4)/16.0; //temp, fraction of a degree

float temperature = (float)(msb + templsb);

if (negSign) temperature = 0 - temperature;

return(temperature);
}

Expand Down Expand Up @@ -236,14 +236,14 @@ void MPL3115A2::setModeActive()
}

//Call with a rate from 0 to 7. See page 33 for table of ratios.
//Sets the over sample rate. Datasheet calls for 128 but you can set it
//Sets the over sample rate. Datasheet calls for 128 but you can set it
//from 1 to 128 samples. The higher the oversample rate the greater
//the time between data samples.
void MPL3115A2::setOversampleRate(byte sampleRate)
{
if(sampleRate > 7) sampleRate = 7; //OS cannot be larger than 0b.0111
sampleRate <<= 3; //Align it for the CTRL_REG1 register

byte tempSetting = IIC_Read(CTRL_REG1); //Read current settings
tempSetting &= 0xc7; // B11000111; //Clear out old OS bits
tempSetting |= sampleRate; //Mask in new OS bits
Expand All @@ -254,7 +254,7 @@ void MPL3115A2::setOversampleRate(byte sampleRate)
//test against them. This is recommended in datasheet during setup.
void MPL3115A2::enableEventFlags()
{
IIC_Write(PT_DATA_CFG, 0x07); // Enable all three pressure and temp event flags
IIC_Write(PT_DATA_CFG, 0x07); // Enable all three pressure and temp event flags
}

//Clears then sets the OST bit which causes the sensor to immediately take another reading
Expand Down Expand Up @@ -290,4 +290,3 @@ void MPL3115A2::IIC_Write(byte regAddr, byte value)
_i2cPort->write(value);
_i2cPort->endTransmission(true);
}

18 changes: 9 additions & 9 deletions src/SparkFunMPL3115A2.h
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Original file line number Diff line number Diff line change
@@ -1,18 +1,18 @@
/*
/*
MPL3115A2 Barometric Pressure Sensor Library
By: Nathan Seidle
SparkFun Electronics
Date: September 24th, 2013
License: This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).

Get pressure, altitude and temperature from the MPL3115A2 sensor.

Updated by PaulZC: October 19th, 2019

*/
#ifndef _SPARKFUN_MPL3115A2_H_
#define _SPARKFUN_MPL3115A2_H_

#ifndef _SPARKFUN_MPL3115A2_H_
#define _SPARKFUN_MPL3115A2_H_

#include <Arduino.h>

Expand All @@ -21,7 +21,7 @@
// Define MPL3115A2 registers
enum mpl3115a2_regs
{
STATUS = 0x00,
MPLSTATUS = 0x00,
OUT_P_MSB = 0x01,
OUT_P_CSB = 0x02,
OUT_P_LSB = 0x03,
Expand Down Expand Up @@ -66,7 +66,7 @@ enum mpl3115a2_regs
CTRL_REG5 = 0x2A,
OFF_P = 0x2B,
OFF_T = 0x2C,
OFF_H = 0x2D
OFF_H = 0x2D
};


Expand Down