ACS712.h

00001 #ifndef ACS712_H
00002 #define ACS712_H
00003 
00004 /****
00005     This class calculates the current drawn by the robot. It requires that EVERYTHING else is turned off when
00006     calibration is in progress.
00007     Requirement: Turn off mouse sensors somehow.
00008 */
00009 
00010 #include "mbed.h"
00011 //#include "robot.h"
00012 
00013 #define HIGH_CURRENT 130       //increase of current when switch is turned on [mA]
00014 #define LOW_CURRENT 36          //current draw when everything is turned off [mA]
00015 #define SWITCH_PIN PTB18//HIGH_CURRENT_SWITCH
00016 #define SENSOR_PIN PTC2//CURRENTSENSOR_PIN
00017 
00018 #define CALIBRATION_SAMPLES 50 //the number of samples taken for the calibration
00019 
00020 class ACS712
00021 {
00022 private:
00023 
00024     AnalogIn sensor;            //reads the value from current sensor
00025     DigitalOut currentSwitch;   //turn this on to send current through a resistor
00026     
00027     float b;        //offset
00028     float m;        //slope
00029     float current;  //[mA]
00030     float sensor_val;   //[% of 3.3V]
00031     
00032 public:
00033     
00034     ACS712();
00035     void calibrate();          //calculates m and b
00036     float get_current();        //returns the current [mA]
00037     float read_sensor();        //reads sensor [% of 3.3V]
00038     float read_sensor(int n, int t);    //reads sensor <n> times and returns the average
00039 };
00040 
00041 
00042 
00043 #endif