christian l.
Light detector with simple LDR and LCD display,there exist no calibration
main.cpp@0:f1db4613080a, 2011-02-15 (annotated)
- Committer:
- christian
- Date:
- Tue Feb 15 21:24:10 2011 +0000
- Revision:
- 0:f1db4613080a
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| christian | 0:f1db4613080a | 1 | #include "mbed.h" |
| christian | 0:f1db4613080a | 2 | #include "TextLCD.h" |
| christian | 0:f1db4613080a | 3 | |
| christian | 0:f1db4613080a | 4 | TextLCD lcd(p10, p12, p15, p16, p29, p30); // rs, e, d0-d3 |
| christian | 0:f1db4613080a | 5 | |
| christian | 0:f1db4613080a | 6 | AnalogIn Vin(p20); // 3.3V Vout - 4K7 resistor - pin20 - LDR -100 ohm resistor - GND |
| christian | 0:f1db4613080a | 7 | |
| christian | 0:f1db4613080a | 8 | main() |
| christian | 0:f1db4613080a | 9 | { |
| christian | 0:f1db4613080a | 10 | while(1) { |
| christian | 0:f1db4613080a | 11 | int x = 0; |
| christian | 0:f1db4613080a | 12 | |
| christian | 0:f1db4613080a | 13 | for (int i=0;i<=100;i++){ |
| christian | 0:f1db4613080a | 14 | x = x + 1000*(1-Vin.read()); //build average from 100 values |
| christian | 0:f1db4613080a | 15 | wait (0.01); |
| christian | 0:f1db4613080a | 16 | } |
| christian | 0:f1db4613080a | 17 | x=x/100; |
| christian | 0:f1db4613080a | 18 | lcd.cls(); |
| christian | 0:f1db4613080a | 19 | lcd.printf("light intensity\n"); |
| christian | 0:f1db4613080a | 20 | lcd.printf("%d\n",x); //value x is only relative,maybe anybody could calibrate it ? |
| christian | 0:f1db4613080a | 21 | |
| christian | 0:f1db4613080a | 22 | } |
| christian | 0:f1db4613080a | 23 | } |