Geofrey Marcel / FastPWM

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Fork of FastPWM by Erik -

FastPWM_common.cpp@4:a7b9f778c4b4, 2013-08-13 (annotated)

Committer:
Sissors
Date:
Tue Aug 13 16:54:06 2013 +0000
Revision:
4:a7b9f778c4b4
Child:
6:0f57969697b6
v2.0

; Added KL25Z/LPC11u24 support

; Added prescalers

; Direct tick changes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sissors 4:a7b9f778c4b4 1 #include "FastPWM.h"
Sissors 4:a7b9f778c4b4 2
Sissors 4:a7b9f778c4b4 3 FastPWM::FastPWM(PinName pin, int prescaler) : PwmOut(pin) {
Sissors 4:a7b9f778c4b4 4 initFastPWM();
Sissors 4:a7b9f778c4b4 5 this->prescaler(prescaler);
Sissors 4:a7b9f778c4b4 6
Sissors 4:a7b9f778c4b4 7 //Set duty cycle on 0%, period on 20ms
Sissors 4:a7b9f778c4b4 8 _duty=0;
Sissors 4:a7b9f778c4b4 9 period(0.02);
Sissors 4:a7b9f778c4b4 10
Sissors 4:a7b9f778c4b4 11
Sissors 4:a7b9f778c4b4 12 }
Sissors 4:a7b9f778c4b4 13
Sissors 4:a7b9f778c4b4 14 void FastPWM::period(double seconds) {
Sissors 4:a7b9f778c4b4 15 if (dynamicPrescaler)
Sissors 4:a7b9f778c4b4 16 calcPrescaler((uint64_t)(seconds * (double) SystemCoreClock));
Sissors 4:a7b9f778c4b4 17
Sissors 4:a7b9f778c4b4 18 period_ticks(seconds * dticks + 0.5);
Sissors 4:a7b9f778c4b4 19 pulsewidth_ticks(getPeriod() * _duty);
Sissors 4:a7b9f778c4b4 20 }
Sissors 4:a7b9f778c4b4 21
Sissors 4:a7b9f778c4b4 22 void FastPWM::period_ms(int ms) {
Sissors 4:a7b9f778c4b4 23 if (dynamicPrescaler)
Sissors 4:a7b9f778c4b4 24 calcPrescaler(ms * (SystemCoreClock / 1000));
Sissors 4:a7b9f778c4b4 25
Sissors 4:a7b9f778c4b4 26 period_ticks(ms * iticks_ms);
Sissors 4:a7b9f778c4b4 27 pulsewidth_ticks(getPeriod() * _duty);
Sissors 4:a7b9f778c4b4 28 }
Sissors 4:a7b9f778c4b4 29
Sissors 4:a7b9f778c4b4 30 void FastPWM::period_us(int us) {
Sissors 4:a7b9f778c4b4 31 if (dynamicPrescaler)
Sissors 4:a7b9f778c4b4 32 calcPrescaler(us * (SystemCoreClock / 1000000));
Sissors 4:a7b9f778c4b4 33
Sissors 4:a7b9f778c4b4 34 period_ticks(us * iticks_us);
Sissors 4:a7b9f778c4b4 35 pulsewidth_ticks(getPeriod() * _duty);
Sissors 4:a7b9f778c4b4 36 }
Sissors 4:a7b9f778c4b4 37
Sissors 4:a7b9f778c4b4 38 void FastPWM::period_us(double us) {
Sissors 4:a7b9f778c4b4 39 if (dynamicPrescaler)
Sissors 4:a7b9f778c4b4 40 calcPrescaler((uint64_t)(us * (double)(SystemCoreClock / 1000000)));
Sissors 4:a7b9f778c4b4 41
Sissors 4:a7b9f778c4b4 42 period_ticks(us * dticks_us + 0.5);
Sissors 4:a7b9f778c4b4 43 pulsewidth_ticks(getPeriod() * _duty);
Sissors 4:a7b9f778c4b4 44 }
Sissors 4:a7b9f778c4b4 45
Sissors 4:a7b9f778c4b4 46 void FastPWM::pulsewidth(double seconds) {
Sissors 4:a7b9f778c4b4 47 pulsewidth_ticks(seconds * dticks + 0.5);
Sissors 4:a7b9f778c4b4 48 }
Sissors 4:a7b9f778c4b4 49
Sissors 4:a7b9f778c4b4 50 void FastPWM::pulsewidth_ms(int ms) {
Sissors 4:a7b9f778c4b4 51 pulsewidth_ticks(ms * iticks_ms);
Sissors 4:a7b9f778c4b4 52 }
Sissors 4:a7b9f778c4b4 53
Sissors 4:a7b9f778c4b4 54 void FastPWM::pulsewidth_us(int us) {
Sissors 4:a7b9f778c4b4 55 pulsewidth_ticks(us * iticks_us);
Sissors 4:a7b9f778c4b4 56 }
Sissors 4:a7b9f778c4b4 57
Sissors 4:a7b9f778c4b4 58 void FastPWM::pulsewidth_us(double us) {
Sissors 4:a7b9f778c4b4 59 pulsewidth_ticks(us * dticks_us + 0.5);
Sissors 4:a7b9f778c4b4 60 }
Sissors 4:a7b9f778c4b4 61
Sissors 4:a7b9f778c4b4 62 void FastPWM::write(double duty) {
Sissors 4:a7b9f778c4b4 63 _duty=duty;
Sissors 4:a7b9f778c4b4 64 pulsewidth_ticks(duty*getPeriod());
Sissors 4:a7b9f778c4b4 65 }
Sissors 4:a7b9f778c4b4 66
Sissors 4:a7b9f778c4b4 67 double FastPWM::read( void ) {
Sissors 4:a7b9f778c4b4 68 return _duty;
Sissors 4:a7b9f778c4b4 69 }
Sissors 4:a7b9f778c4b4 70
Sissors 4:a7b9f778c4b4 71 FastPWM & FastPWM::operator= (double value) {
Sissors 4:a7b9f778c4b4 72 write(value);
Sissors 4:a7b9f778c4b4 73 return(*this);
Sissors 4:a7b9f778c4b4 74 }
Sissors 4:a7b9f778c4b4 75
Sissors 4:a7b9f778c4b4 76 FastPWM::operator double() {
Sissors 4:a7b9f778c4b4 77 return _duty;
Sissors 4:a7b9f778c4b4 78 }
Sissors 4:a7b9f778c4b4 79
Sissors 4:a7b9f778c4b4 80 int FastPWM::prescaler(int value) {
Sissors 4:a7b9f778c4b4 81 int retval;
Sissors 4:a7b9f778c4b4 82 if (value == -1) {
Sissors 4:a7b9f778c4b4 83 dynamicPrescaler = true;
Sissors 4:a7b9f778c4b4 84 value = 0;
Sissors 4:a7b9f778c4b4 85 }
Sissors 4:a7b9f778c4b4 86 else
Sissors 4:a7b9f778c4b4 87 dynamicPrescaler = false;
Sissors 4:a7b9f778c4b4 88
Sissors 4:a7b9f778c4b4 89 retval = setPrescaler(value);
Sissors 4:a7b9f778c4b4 90 updateTicks(retval);
Sissors 4:a7b9f778c4b4 91 return retval;
Sissors 4:a7b9f778c4b4 92 }
Sissors 4:a7b9f778c4b4 93
Sissors 4:a7b9f778c4b4 94 void FastPWM::updateTicks( uint32_t prescaler ) {
Sissors 4:a7b9f778c4b4 95 dticks = SystemCoreClock / (double)prescaler;
Sissors 4:a7b9f778c4b4 96 dticks_us = SystemCoreClock / (double)prescaler / 1000000.0f;
Sissors 4:a7b9f778c4b4 97 iticks_ms = SystemCoreClock / prescaler / 1000;
Sissors 4:a7b9f778c4b4 98 iticks_us = SystemCoreClock / prescaler / 1000000;
Sissors 4:a7b9f778c4b4 99 }
Sissors 4:a7b9f778c4b4 100
Sissors 4:a7b9f778c4b4 101 int FastPWM::calcPrescaler(uint64_t clocks) {
Sissors 4:a7b9f778c4b4 102 uint32_t scale = (clocks >> bits) + 1;
Sissors 4:a7b9f778c4b4 103 uint32_t retval = setPrescaler(scale);
Sissors 4:a7b9f778c4b4 104 updateTicks(retval);
Sissors 4:a7b9f778c4b4 105 return retval;
Sissors 4:a7b9f778c4b4 106 }