PWMAverage.cpp

00001 #include "PWMAverage.h"
00002 
00003 #define PWMA_PCLK 96000000
00004 
00005 
00006 PWMAverage * PWMAverage::instance;
00007 
00008 
00009 void PWMAverage::_tisr()
00010 {
00011     //printf(".");
00012     int cr0 = LPC_TIM2->CR0;
00013     int cr1 = LPC_TIM2->CR1;
00014     
00015     LPC_TIM2->IR = 0x3F;
00016     
00017     LPC_TIM2->TCR = 3;
00018     LPC_TIM2->TCR = 1;
00019     
00020     //LPC_NVIC->ICPR0 |= (1<<3)
00021     
00022     if(!instance->starting)
00023     {
00024     instance->total += cr1 + 82;
00025     instance->totalup += cr0 + 82;
00026     instance->count_++;
00027     }
00028     else instance->starting = false;
00029 
00030     }
00031 
00032 PWMAverage::PWMAverage(PinName cap0, PinName cap1)
00033 {
00034     prescaler_point = 0x0;
00035     configure();
00036     stop();
00037     
00038     timeMult = (1/PWMA_PCLK)*(prescaler_point+1);
00039     timeDiv = PWMA_PCLK/(prescaler_point+1);
00040     instance = this;
00041 }
00042 
00043 void PWMAverage::reset()
00044 {
00045     count_ = 0;
00046     total = 0;
00047     totalup = 0;
00048     LPC_TIM2->TCR = 2;
00049     LPC_TIM2->TCR = 0;
00050 }
00051 
00052 void PWMAverage::start()
00053 {
00054     //reset();
00055     starting = true;
00056     enable(true);
00057     NVIC_EnableIRQ(TIMER2_IRQn);
00058 }
00059 
00060 void PWMAverage::stop()
00061 {
00062     enable(false);
00063     NVIC_DisableIRQ(TIMER2_IRQn);
00064 }
00065 
00066 float PWMAverage::read()
00067 {
00068     if(period() != 0) return float(avg_up()/period());
00069     else return 0;
00070 }
00071 
00072 double PWMAverage::avg_up()
00073 {
00074     if(count_!= 0)    return (double(totalup)/timeDiv)/double(count_);
00075     else return 0;
00076     
00077 }
00078 
00079 float PWMAverage::avg_UP()
00080 {
00081     if(count_!= 0)    return float((double(totalup)/timeDiv)/double(count_));
00082     else return 0;
00083 }
00084 
00085 double PWMAverage::avg_down()
00086 {
00087     if(count_!= 0)    return (double(total-totalup)/timeDiv)/double(count_);
00088     else return 0;
00089 }
00090 
00091 double PWMAverage::period()
00092 {
00093     if(count_!= 0)    return (double(total)/timeDiv)/double(count_);
00094     else return 0;
00095 }
00096 
00097 int PWMAverage::count()
00098 {
00099     return count_;
00100 }
00101 
00102 void PWMAverage::enable(bool yn)
00103 {
00104     LPC_TIM2->TCR = yn;
00105 }
00106 
00107 void PWMAverage::configure()
00108 {
00109     //Power Periferal
00110     
00111     LPC_SC->PCONP |= (1<<22);
00112     
00113     //Setup Pins
00114     
00115     LPC_PINCON->PINSEL0 |= (0x3<<8);
00116     LPC_PINCON->PINSEL0 |= (0x3<<10);
00117     
00118     //Setup clock source
00119     
00120     LPC_SC->PCLKSEL1 |= (0x1<<12);
00121 
00122     //Setup PC
00123     
00124     LPC_TIM2->PR = prescaler_point;
00125     
00126     //Setup CAP0 - Store on fall
00127     
00128     LPC_TIM2->CCR |= 0x2; 
00129     
00130     //Setup CAP1 - Store on rise, interrupt
00131     
00132     LPC_TIM2->CCR |= 0x5<<3;
00133     
00134     //Setup IRQs
00135     NVIC_DisableIRQ(TIMER2_IRQn);
00136     NVIC_SetVector(TIMER2_IRQn, (uint32_t)&_tisr);
00137     NVIC_EnableIRQ(TIMER2_IRQn);
00138     //
00139 }