/*
* reads TLS230R module
* sends to serial monitor
*/
// setup the TLS230R to Arduion mapping
#define TSL_FREQ_PIN 2 // output use digital pin2 for interrupt
#define TSL_S0 3
#define TSL_S1 4
#define TSL_S2 5
#define TSL_S3 6
#define READ_TM 1000 // milleseconds between frequency calculations
int calcSensitivity;
unsigned long sensitivityHighThresh = 2000;
unsigned long sensitivityLowThresh = 100000;
unsigned long pulseCount = 0;
unsigned long currentTime = millis();
unsigned long startTime = currentTime;
unsigned int tm_diff = 0;
// freq will be modified by the interrupt handler so needs to be volatile
// freq holds the latest frequency calculation
unsigned long frequency;
float uWattCm2;
volatile unsigned long curPulseCount;
unsigned int count = 0;
unsigned int scale; // holds the TLS scale value, see below
void setup() {
Serial.begin(57600);
sensitivity(1);
Serial.print("Sensitivity ");
Serial.println(calcSensitivity, DEC);
Serial.println("Start...");
// attach interrupt to pin2, send output pin of TSL230R to arduino 2
// call handler on each rising pulse
attachInterrupt(0, add_pulse, RISING);
pinMode(TSL_FREQ_PIN, INPUT);
pinMode(TSL_S0, OUTPUT);
pinMode(TSL_S1, OUTPUT);
pinMode(TSL_S2, OUTPUT);
pinMode(TSL_S3, OUTPUT);
digitalWrite(TSL_S2, HIGH); // S2 and S3 HIGH = /100 output scaling
digitalWrite(TSL_S3, HIGH);
scale = 100; // set this to match TSL_S2 and TSL_S3
}
void loop() {
// this is just for debugging
// it shows that you can sample freq whenever you need it
// even though it is calculated once a second
// I am dislplaying it every 2 seconds
// note that the first time that freq is calculated, it is bogus
count++;
Serial.print(count);
Serial.print("\tuW/cm: ");
Serial.print(getUwattCm2(), DEC);
Serial.print("\tfrequency: ");
Serial.println(frequency, DEC);
setSensitivity();
delay(1000);
}
void add_pulse() {
// increase pulse count
pulseCount++;
// DON'T calculate the frequency every READ_TM ms
// just store the pulse count to be used outside of the interrupt
currentTime = millis();
if( currentTime - startTime >= READ_TM )
{
curPulseCount = pulseCount; // use curPulseCount for calculating freq/uW
pulseCount = 0;
startTime = millis();
}
}
long getUwattCm2() {
// copy pulse counter and multiply.
// the multiplication is necessary for the current
// frequency scaling level.
frequency = curPulseCount * scale;
// get uW observed - assume 640nm wavelength
// calc_sensitivity is our divide-by to map to a given signal strength
// for a given sensitivity (each level of greater sensitivity reduces the signal
// (uW) by a factor of 10)
float uw_cm2 = (float) frequency / (float) calcSensitivity;
// extrapolate into entire cm2 area
uWattCm2 = uw_cm2 * ( (float) 1 / (float) 0.0136 );
return(uWattCm2);
}
void setSensitivity()
{
getUwattCm2();
if (uWattCm2 < sensitivityHighThresh)
{
sensitivity(3);
return;
}
if (uWattCm2 > sensitivityLowThresh )
{
sensitivity(1);
return;
}
sensitivity(2);
}
void sensitivity(uint8_t level)
{
switch (level)
{
case 1:
if (calcSensitivity != 10)
{
Serial.println("Now at low sensitivity.");
}
digitalWrite(TSL_S0, HIGH); // S0 HIGH and S1 LOW = 1x sensitivity
digitalWrite(TSL_S1, LOW);
calcSensitivity = 10;
break;
case 2:
if (calcSensitivity != 100)
{
Serial.println("Now at medim sensitivity.");
}
digitalWrite(TSL_S0, LOW); // S0 LOW and S1 HIGH = 10x sensitivity
digitalWrite(TSL_S1, HIGH);
calcSensitivity = 100;
break;
case 3:
if (calcSensitivity != 1000)
{
Serial.println("Now at high sensitivity.");
}
digitalWrite(TSL_S0, HIGH); // S0 HIGH and S1 HIGH = 100x sensitivity
digitalWrite(TSL_S1, HIGH);
calcSensitivity = 1000;
break;
}
return;
}
