2020-02-17 17:22:11 +01:00

86 lines
1.4 KiB
C++

//
// FILE: ML8511.cpp
// AUTHOR: Rob.Tillaart@gmail.com
// VERSION: 0.1.1
// PURPOSE: ML8511 - UV sensor - library for Arduino
//
// HISTORY:
// 0.1.0 2020-02-03 - initial version
// 0.1.1 2020-02-17 - added _voltPerStep() to support more boards
//
#include "ML8511.h"
/////////////////////////////////////////////////////
//
// PUBLIC
//
ML8511::ML8511(uint8_t analogPin, uint8_t enablePin)
{
_analogPin = analogPin;
_voltsPerStep = 5.0/1023;
if (enablePin >= 0)
{
_enablePin = enablePin;
pinMode(_enablePin, OUTPUT);
_enabled = false;
enable();
}
else
{
_enabled = true;
}
};
float ML8511::getUV(uint8_t energyMode)
{
if (!_enabled)
{
enable();
// datasheet page 5 states wait for max 1 millisecond
uint32_t start = micros();
while (micros() - start < 1000)
{
yield();
}
}
float voltage = analogRead(_analogPin) * _voltsPerStep;
if (energyMode == LOW)
{
disable();
}
// see datasheet - page 4
// mW/cm2 @ 365 nm
// @ 25 Celcius
// formula estimated on graph
if (voltage <= 1.0)
{
return 0.0;
}
voltage -= 1.0; // subtract for zero point.
float mW = voltage * (15.0 / 1.8);
return mW;
}
void ML8511::setVoltsPerStep(float voltage, uint32_t steps)
{
if (voltage > 0.0) _voltsPerStep = voltage / steps;
}
void ML8511::enable()
{
digitalWrite(_enablePin, HIGH);
_enabled = true;
};
void ML8511::disable()
{
digitalWrite(_enablePin, LOW);
_enabled = false;
};
// END OF FILE