Rev Author Line No. Line
2202 kaklik 1 // I2C Light Sensor
2  
3 #include <Wire.h>
2237 kaklik 4 #include <math.h>
2202 kaklik 5  
6 #define address 0x44 // A0 = L
2235 kaklik 7 #define SENSE_VIS 0
8 #define SENSE_IR 1
2202 kaklik 9  
2238 kaklik 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
2202 kaklik 15  
2238 kaklik 16  
2202 kaklik 17 void setup()
18 {
19 Wire.begin(); // join i2c bus (address optional for master)
2435 kaklik 20 // I2C pins PC4 - , PC5 -
2202 kaklik 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;
2237 kaklik 28 int light_sensor_setup;
2202 kaklik 29  
2234 kaklik 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  
2235 kaklik 39 int set_light_sensor(int mode)
2234 kaklik 40 {
2235 kaklik 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 }
2234 kaklik 56  
2235 kaklik 57 default:
58 return 3;
59 }
60  
61 // Setup device
62 Wire.beginTransmission(address);
63 Wire.send(0x00); // sends address
64 Wire.send(command); // setup (eye light sensing; one time measurement; measurement range 1)
65 Wire.endTransmission(); // stop transmitting
2236 kaklik 66  
67  
68 // Connect to device and set register address
69 Wire.beginTransmission(address);
70 Wire.send(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.receive())
77 {
78 return 4;
79 Serial.print(data, BIN);
80 }
81 Wire.endTransmission(); // stop transmitting
2237 kaklik 82 light_sensor_setup=command;
2234 kaklik 83 }
84  
2237 kaklik 85 float get_light_measurement()
2234 kaklik 86 {
2237 kaklik 87 int ret=0;
2234 kaklik 88  
89 // Connect to device and set register address
90 Wire.beginTransmission(address);
91 Wire.send(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);
2237 kaklik 97 ret = Wire.receive();
2234 kaklik 98 Wire.endTransmission(); // stop transmitting
99  
100 // Connect to device and set register address
101 Wire.beginTransmission(address);
102 Wire.send(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);
2237 kaklik 108 ret +=256 * Wire.receive();
2234 kaklik 109 Wire.endTransmission(); // stop transmitting
110  
2237 kaklik 111 return (1000.0/pow(2.0,16)*ret);
2234 kaklik 112 }
113  
2202 kaklik 114 void loop()
115 {
2236 kaklik 116 int lux=0;
2202 kaklik 117  
2236 kaklik 118 set_light_sensor(SENSE_VIS); //setup sensor for visible measuring
119 led_blink(); // Delay for measurement
120 Serial.print("lux=");
2237 kaklik 121 Serial.println(get_light_measurement(),2);
2202 kaklik 122  
2236 kaklik 123 set_light_sensor(SENSE_IR); // setup sensor for infrared measuring
124 led_blink(); // Delay for measurement
125 Serial.print("luxIR=");
2237 kaklik 126 Serial.println(get_light_measurement(), 2); // data print
2202 kaklik 127 }
128