Rev Author Line No. Line
2436 kaklik 1 // I2C Light Sensor
2  
3 #include <Wire.h>
4 #include <math.h>
5  
6 #define address 0x44 // A0 = L
7 #define SENSE_VIS 0
8 #define SENSE_IR 1
9  
10 #define LIGHT_AUTORANGE 0
11 #define LIGHT_RANGE1 1
12 #define LIGHT_RANGE2 2
13 #define LIGHT_RANGE3 3
14 #define LIGHT_RANGE4 4
15  
16  
17 void setup()
18 {
19 Wire.begin(); // join i2c bus (address optional for master)
2441 kaklik 20 // I2C pins PC4 - SDA , PC5 - SCL
2436 kaklik 21 //
22 pinMode(3, OUTPUT); // LED pro blikani, aby bylo videt, ze to neco dela
23 Serial.begin(9600); // Zmerena intenzita osvetleni se bude vypisovat na seriovou linku
2441 kaklik 24 Serial.println("LABduino luxmeter demo - (c) MLAB.cz, kakl 2012");
2436 kaklik 25 }
26  
27 int data = 0;
28 int light_sensor_setup;
29  
30 void led_blink()
31 {
2441 kaklik 32 digitalWrite(3, HIGH); // set the LED on
2440 kaklik 33 delay(100);
2441 kaklik 34 digitalWrite(3, LOW); // set the LED off
2440 kaklik 35 delay(700);
2436 kaklik 36 }
37  
38  
39 int set_light_sensor(int mode)
40 {
41 int command;
42  
43 switch (mode)
44 {
45 case SENSE_VIS:
46 {
2438 kaklik 47 command=0b11000001; // setup (eye light sensing; measurement range 2)
2436 kaklik 48 break;
49 }
50  
51 case SENSE_IR:
52 {
2438 kaklik 53 command=0b11100001; // setup (eye light sensing; measurement range 2 [4000 lx])
2436 kaklik 54 break;
55 }
56  
57 default:
2438 kaklik 58 return 3;
2436 kaklik 59 }
60  
61 // Setup device
62 Wire.beginTransmission(address);
2438 kaklik 63 Wire.write(byte(0x00)); // sends address
64 Wire.write(byte(command)); // setup (eye light sensing; one time measurement; measurement range 1)
2436 kaklik 65 Wire.endTransmission(); // stop transmitting
66  
67  
68 // Connect to device and set register address
69 Wire.beginTransmission(address);
2438 kaklik 70 Wire.write(byte(0x00)); // sends address (command register)
2436 kaklik 71 Wire.endTransmission(); // stop transmitting
72  
73 // verify written command byte
74 Wire.beginTransmission(address);
75 Wire.requestFrom(address, 1);
76 if (command != Wire.read())
77 {
78 return 4;
79 Serial.print(data, BIN);
80 }
81 Wire.endTransmission(); // stop transmitting
82 light_sensor_setup=command;
83 }
84  
85 float get_light_measurement()
86 {
2438 kaklik 87 unsigned int ret=0;
2436 kaklik 88  
89 // Connect to device and set register address
90 Wire.beginTransmission(address);
2438 kaklik 91 Wire.write(byte(0x01)); // sends address of LSB reagister
2436 kaklik 92 Wire.endTransmission(); // stop transmitting
93  
94 // Connect to device and request one byte
95 Wire.beginTransmission(address);
96 Wire.requestFrom(address, 1);
97 ret = Wire.read();
98 Wire.endTransmission(); // stop transmitting
99  
100 // Connect to device and set register address
101 Wire.beginTransmission(address);
2438 kaklik 102 Wire.write(byte(0x02)); // sends address of MSB register
2436 kaklik 103 Wire.endTransmission(); // stop transmitting
104  
105 // Connect to device and request one byte
106 Wire.beginTransmission(address);
107 Wire.requestFrom(address, 1);
108 ret +=256 * Wire.read();
109 Wire.endTransmission(); // stop transmitting
110  
2438 kaklik 111 return (4000.0/pow(2.0,16)*ret);
2436 kaklik 112 }
113  
114 void loop()
115 {
116 int lux=0;
117  
118 set_light_sensor(SENSE_VIS); //setup sensor for visible measuring
119 led_blink(); // Delay for measurement
2438 kaklik 120 Serial.print("luxVIS\t");
121 Serial.print(get_light_measurement(),1);
122 Serial.print("\t");
2436 kaklik 123  
124 set_light_sensor(SENSE_IR); // setup sensor for infrared measuring
125 led_blink(); // Delay for measurement
2438 kaklik 126 Serial.print("luxIR\t");
127 Serial.println(get_light_measurement(),1); // data print
2436 kaklik 128 }
129