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)
20 // I2C pins PC4 - , PC5 -
21 //
22 pinMode(3, OUTPUT); // LED pro blikani, aby bylo videt, ze to neco dela
23 pinMode(5, OUTPUT); // LED pro blikani, aby bylo videt, ze to neco dela
24 Serial.begin(9600); // Zmerena intenzita osvetleni se bude vypisovat na seriovou linku
25 }
26  
27 int data = 0;
28 int light_sensor_setup;
29  
30 void led_blink()
31 {
32 digitalWrite(3, HIGH); // set the LED on
33 delay(500);
34 digitalWrite(3, LOW); // set the LED off
35 delay(500);
36 }
37  
38  
39 int set_light_sensor(int mode)
40 {
41 int command;
42  
43 switch (mode)
44 {
45 case SENSE_VIS:
46 {
47 command=0b11000000; // setup (eye light sensing; one time measurement; measurement range 1)
48 break;
49 }
50  
51 case SENSE_IR:
52 {
53 command=0b11100000; // setup (eye light sensing; measurement range 2 [4000 lx])
54 break;
55 }
56  
57 default:
58 return 3;
59 }
60  
61 // Setup device
62 Wire.beginTransmission(address);
63 Wire.write(0x00); // sends address
64 Wire.write(command); // setup (eye light sensing; one time measurement; measurement range 1)
65 Wire.endTransmission(); // stop transmitting
66  
67  
68 // Connect to device and set register address
69 Wire.beginTransmission(address);
70 Wire.write(0x00); // sends address (command register)
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 {
87 int ret=0;
88  
89 // Connect to device and set register address
90 Wire.beginTransmission(address);
91 Wire.write(0x01); // sends address of LSB reagister
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);
102 Wire.write(0x02); // sends address of MSB register
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  
111 return (1000.0/pow(2.0,16)*ret);
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
120 Serial.print("lux=");
121 Serial.println(get_light_measurement(),2);
122  
123 set_light_sensor(SENSE_IR); // setup sensor for infrared measuring
124 led_blink(); // Delay for measurement
125 Serial.print("luxIR=");
126 Serial.println(get_light_measurement(), 2); // data print
127 }
128