Diff: FastPWM_common.cpp

Revision:

4:a7b9f778c4b4

Child:

6:0f57969697b6

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/FastPWM_common.cpp	Tue Aug 13 16:54:06 2013 +0000
@@ -0,0 +1,106 @@
+#include "FastPWM.h"
+
+FastPWM::FastPWM(PinName pin, int prescaler) : PwmOut(pin) {
+    initFastPWM();
+    this->prescaler(prescaler);
+    
+    //Set duty cycle on 0%, period on 20ms
+    _duty=0; 
+    period(0.02);
+    
+
+}
+
+void FastPWM::period(double seconds) {
+    if (dynamicPrescaler)
+        calcPrescaler((uint64_t)(seconds * (double) SystemCoreClock));
+
+     period_ticks(seconds * dticks + 0.5);
+    pulsewidth_ticks(getPeriod() * _duty);
+}
+
+void FastPWM::period_ms(int ms) {
+    if (dynamicPrescaler)
+        calcPrescaler(ms * (SystemCoreClock / 1000));
+        
+    period_ticks(ms * iticks_ms);
+    pulsewidth_ticks(getPeriod() * _duty);
+}
+
+void FastPWM::period_us(int us) {
+    if (dynamicPrescaler)
+        calcPrescaler(us * (SystemCoreClock / 1000000));
+    
+    period_ticks(us * iticks_us);
+    pulsewidth_ticks(getPeriod() * _duty);
+}
+
+void FastPWM::period_us(double us) {
+    if (dynamicPrescaler)
+        calcPrescaler((uint64_t)(us * (double)(SystemCoreClock / 1000000)));
+        
+    period_ticks(us * dticks_us + 0.5);
+    pulsewidth_ticks(getPeriod() * _duty);
+}
+
+void FastPWM::pulsewidth(double seconds) {
+    pulsewidth_ticks(seconds * dticks + 0.5);
+}
+
+void FastPWM::pulsewidth_ms(int ms) {
+    pulsewidth_ticks(ms * iticks_ms);
+}
+
+void FastPWM::pulsewidth_us(int us) {
+    pulsewidth_ticks(us * iticks_us);
+}
+
+void FastPWM::pulsewidth_us(double us) {
+    pulsewidth_ticks(us * dticks_us + 0.5);
+}
+
+void FastPWM::write(double duty) {
+    _duty=duty;
+    pulsewidth_ticks(duty*getPeriod());
+}
+
+double FastPWM::read( void ) {
+    return _duty;
+    }
+    
+FastPWM & FastPWM::operator= (double value) {
+    write(value);
+    return(*this);
+    }
+    
+FastPWM::operator double() {
+    return _duty;
+}
+
+int FastPWM::prescaler(int value) {
+    int retval;
+    if (value == -1) {
+        dynamicPrescaler = true;
+        value = 0;
+    }
+    else
+        dynamicPrescaler = false;
+    
+    retval = setPrescaler(value);
+    updateTicks(retval);
+    return retval;
+}
+
+void FastPWM::updateTicks( uint32_t prescaler ) {
+    dticks = SystemCoreClock / (double)prescaler;
+    dticks_us = SystemCoreClock / (double)prescaler / 1000000.0f;
+    iticks_ms = SystemCoreClock / prescaler / 1000;
+    iticks_us = SystemCoreClock / prescaler / 1000000;
+}
+
+int FastPWM::calcPrescaler(uint64_t clocks) {
+    uint32_t scale = (clocks >> bits) + 1;
+    uint32_t retval = setPrescaler(scale);
+    updateTicks(retval);
+    return retval;
+}     
\ No newline at end of file