implement wrapper class with agc from library example code

This commit is contained in:
interfisch 2020-11-01 13:25:52 +01:00
parent ecb468cb52
commit ed77d41b7a
2 changed files with 133 additions and 0 deletions

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src/tcs34725_agc.cpp Normal file
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//#include <Wire.h>
//#include "Adafruit_TCS34725.h"
#include "tcs34725_agc.h"
//
// Gain/time combinations to use and the min/max limits for hysteresis
// that avoid saturation. They should be in order from dim to bright.
//
// Also set the first min count and the last max count to 0 to indicate
// the start and end of the list.
//
const tcs34725::tcs_agc tcs34725::agc_lst[] = {
{ TCS34725_GAIN_60X, TCS34725_INTEGRATIONTIME_700MS, 0, 20000 },
{ TCS34725_GAIN_60X, TCS34725_INTEGRATIONTIME_154MS, 4990, 63000 },
{ TCS34725_GAIN_16X, TCS34725_INTEGRATIONTIME_154MS, 16790, 63000 },
{ TCS34725_GAIN_4X, TCS34725_INTEGRATIONTIME_154MS, 15740, 63000 },
{ TCS34725_GAIN_1X, TCS34725_INTEGRATIONTIME_154MS, 15740, 0 }
};
tcs34725::tcs34725() : agc_cur(0), isAvailable(0), isSaturated(0) {
}
// initialize the sensor
boolean tcs34725::begin(void) {
tcs = Adafruit_TCS34725(agc_lst[agc_cur].at, agc_lst[agc_cur].ag);
if ((isAvailable = tcs.begin()))
setGainTime();
return(isAvailable);
}
// Set the gain and integration time
void tcs34725::setGainTime(void) {
tcs.setGain(agc_lst[agc_cur].ag);
tcs.setIntegrationTime(agc_lst[agc_cur].at);
atime = int(agc_lst[agc_cur].at);
atime_ms = ((256 - atime) * 2.4);
switch(agc_lst[agc_cur].ag) {
case TCS34725_GAIN_1X:
againx = 1;
break;
case TCS34725_GAIN_4X:
againx = 4;
break;
case TCS34725_GAIN_16X:
againx = 16;
break;
case TCS34725_GAIN_60X:
againx = 60;
break;
}
}
// Retrieve data from the sensor and do the calculations
void tcs34725::getData(void) {
// read the sensor and autorange if necessary
tcs.getRawData(&r, &g, &b, &c);
while(1) {
if (agc_lst[agc_cur].maxcnt && c > agc_lst[agc_cur].maxcnt)
agc_cur++;
else if (agc_lst[agc_cur].mincnt && c < agc_lst[agc_cur].mincnt)
agc_cur--;
else break;
setGainTime();
delay((256 - atime) * 2.4 * 2); // shock absorber
tcs.getRawData(&r, &g, &b, &c);
break;
}
// DN40 calculations
ir = (r + g + b > c) ? (r + g + b - c) / 2 : 0;
r_comp = r - ir;
g_comp = g - ir;
b_comp = b - ir;
c_comp = c - ir;
cratio = float(ir) / float(c);
saturation = ((256 - atime) > 63) ? 65535 : 1024 * (256 - atime);
saturation75 = (atime_ms < 150) ? (saturation - saturation / 4) : saturation;
isSaturated = (atime_ms < 150 && c > saturation75) ? 1 : 0;
cpl = (atime_ms * againx) / (TCS34725_GA * TCS34725_DF);
maxlux = 65535 / (cpl * 3);
lux = (TCS34725_R_Coef * float(r_comp) + TCS34725_G_Coef * float(g_comp) + TCS34725_B_Coef * float(b_comp)) / cpl;
ct = TCS34725_CT_Coef * float(b_comp) / float(r_comp) + TCS34725_CT_Offset;
}

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src/tcs34725_agc.h Normal file
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//copied from example code: https://github.com/adafruit/Adafruit_TCS34725/blob/master/examples/tcs34725autorange/tcs34725autorange.ino
#ifndef _TCS34725_AGC_H_
#define _TCS34725_AGC_H_
#include <Wire.h>
#include "Adafruit_TCS34725.h"
#define TCS34725_R_Coef 0.136
#define TCS34725_G_Coef 1.000
#define TCS34725_B_Coef -0.444
#define TCS34725_GA 1.0
#define TCS34725_DF 310.0
#define TCS34725_CT_Coef 3810.0
#define TCS34725_CT_Offset 1391.0
// Autorange class for TCS34725
class tcs34725 {
private:
struct tcs_agc {
tcs34725Gain_t ag;
tcs34725IntegrationTime_t at;
uint16_t mincnt;
uint16_t maxcnt;
};
static const tcs_agc agc_lst[];
uint16_t agc_cur;
void setGainTime(void);
Adafruit_TCS34725 tcs;
public:
tcs34725(void);
boolean begin(void);
void getData(void);
boolean isAvailable, isSaturated;
uint16_t againx, atime, atime_ms;
uint16_t r, g, b, c;
uint16_t ir;
uint16_t r_comp, g_comp, b_comp, c_comp;
uint16_t saturation, saturation75;
float cratio, cpl, ct, lux, maxlux;
};
#endif