19 lines
491 B
C++
19 lines
491 B
C++
#include "pwm.h"
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void pwmSetFrequency(uint32_t freq)
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{
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TCCR0A = _BV(COM0B1) | _BV(WGM00) | _BV(WGM01);
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DDRB |= _BV(PB4);
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uint16_t p_ideal = ceil(float(F_CPU) / (freq * 0x100));
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for(int8_t i = PWM_PRESCALER_COUNT - 1; i >= 0 && PWM_PRESCALERS[i] >= p_ideal; i--)
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TCCR0B = _BV(WGM02) | i; // set prescaler
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if(p_ideal)
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OCR0A = (uint8_t) (float(F_CPU) / (freq * PWM_PRESCALERS[TCCR0B & 0x07]));
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}
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void pwmSetValue(uint8_t value)
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{
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OCR0B = value;
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}
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