mirror of
https://github.com/RobTillaart/Arduino.git
synced 2024-09-20 00:55:58 -04:00
99 lines
2.3 KiB
C++
99 lines
2.3 KiB
C++
//
|
|
// FILE: TSL235R.cpp
|
|
// AUTHOR: Rob Tillaart
|
|
// VERSION: 0.1.1
|
|
// PURPOSE: library fot the TSL235R light to frequency convertor
|
|
//
|
|
// HISTORY:
|
|
// 0.1.0 2020-05-29 initial version
|
|
// 0.1.1 2020-06-03 add irradiance_HS()
|
|
|
|
|
|
#include "TSL235R.h"
|
|
|
|
|
|
TSL235R::TSL235R(float voltage)
|
|
{
|
|
_voltage = voltage;
|
|
calculateFactor();
|
|
}
|
|
|
|
|
|
float TSL235R::irradiance(uint32_t Hz)
|
|
{
|
|
return Hz * _factor;
|
|
}
|
|
|
|
|
|
float TSL235R::irradiance(uint32_t pulses, uint32_t milliseconds)
|
|
{
|
|
return (pulses * 1000.0 * _factor) / milliseconds;
|
|
}
|
|
|
|
float TSL235R::irradiance_HS(uint32_t pulses, uint32_t microseconds)
|
|
{
|
|
return (pulses * 1000000.0 * _factor) / microseconds;
|
|
}
|
|
|
|
|
|
void TSL235R::setWavelength(uint16_t wavelength)
|
|
{
|
|
_waveLength = wavelength;
|
|
calculateFactor();
|
|
}
|
|
|
|
|
|
void TSL235R::setVoltage(float voltage)
|
|
{
|
|
_voltage = voltage;
|
|
calculateFactor();
|
|
}
|
|
|
|
void TSL235R::calculateFactor()
|
|
{
|
|
// figure 1 datasheet
|
|
// 1 Khz crosses the line at 35/230 between 1 and 10.
|
|
// so the correctiion factor is 10^0.15217 = 1.419659 = 1.42
|
|
// as the graph is in kHz we need to correct a factor 1000
|
|
// as the irradiance function gets Hz
|
|
const float cf = 0.00142;
|
|
_waveLengthFactor = calcWLF(_waveLength);
|
|
|
|
_voltageFactor = 0.988 + (_voltage - 2.7) * (0.015 / 2.8);
|
|
_factor = cf * _waveLengthFactor * _voltageFactor;
|
|
}
|
|
|
|
|
|
float TSL235R::calcWLF(uint16_t _waveLength)
|
|
{
|
|
// figure 2 datasheet
|
|
// 635 nm is reference 1.000
|
|
// remaining is linear interpolated between points in the graph
|
|
float in[] = { 300, 350, 400, 500, 600, 635, 700, 750, 800, 850, 900, 1000, 1100};
|
|
float out[] = { 0.1, 0.35, 0.5, 0.75, 0.93, 1.00, 1.15, 1.20, 1.15, 1.10, 0.95, 0.40, 0.10};
|
|
return 1.0 / multiMap(_waveLength, in, out, 13);
|
|
}
|
|
|
|
|
|
float TSL235R::multiMap(float val, float * _in, float * _out, uint8_t size)
|
|
{
|
|
// take care the value is within range
|
|
// val = constrain(val, _in[0], _in[size-1]);
|
|
if (val <= _in[0]) return _out[0];
|
|
if (val >= _in[size-1]) return _out[size-1];
|
|
|
|
// search right interval
|
|
uint8_t pos = 1; // _in[0] allready tested
|
|
while(val > _in[pos]) pos++;
|
|
|
|
// this will handle all exact "points" in the _in array
|
|
if (val == _in[pos]) return _out[pos];
|
|
|
|
// interpolate in the right segment for the rest
|
|
return (val - _in[pos-1]) * (_out[pos] - _out[pos-1]) / (_in[pos] - _in[pos-1]) + _out[pos-1];
|
|
}
|
|
|
|
|
|
|
|
// -- END OF FILE --
|