FanPump.h

00001 #ifndef _FILE_FANPUMP_H
00002 #define _FILE_FANPUMP_H
00003 
00004 #include "mbed.h"
00005 
00006 class FanPump{
00007 public:
00008     // Takes Pwmout pin, period (seconds), duty cycle slew rate in second^-1 (1 means duty 0 to 1 occurs over 1 second, 0 means no slew)
00009     // Use slew rate to implement soft start
00010     FanPump(PinName pin, float period, float slew);
00011     void write(float duty);
00012     float read();       // Read the last setpoint
00013     float readRaw();    // Read the raw current duty (may be mid-transition)
00014     void directOff();   // Turn off the channel immediately (no slew)
00015     #ifdef MBED_OPERATORS
00016     operator float() {
00017         return read();
00018     }
00019     FanPump& operator= (float value) {  // Overloaded equals to write function
00020         write(value);
00021         return *(this);
00022     }
00023     #endif
00024     int slew();         // Slew rate callback function
00025 private:
00026     PwmOut pwm;         // mbed PWM out
00027     volatile uint32_t* MR_base;         // pwm channel# match register pointer
00028     volatile uint32_t  period_us;       // pwm period in us, shared by all channels
00029     volatile uint32_t  setPoint_us;     // pwm setpoint (goal) in us
00030     volatile uint32_t  maxChange_us;    // Max pulsewidth change in us allowed for each PWM period to achieve the slew rate
00031 };
00032 
00033 #endif