28 lines
755 B
C++
28 lines
755 B
C++
// Bit bang low frequency PWM.
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//
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// Parameters:
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// outputPin (byte) - Pin number to output PWM.
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// dutyCycle (byte) - PWM period from 0 - 100.
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void slowPWM(byte outputPin, byte dutyCycle, unsigned long period)
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{
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static byte outputState = LOW;
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static unsigned long lastSwitchTime = 0;
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unsigned long onTime = (dutyCycle * period) / 100;
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unsigned long offTime = period - onTime;
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unsigned long currentTime = millis();
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if (outputState == HIGH && (currentTime - lastSwitchTime >= onTime))
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{
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lastSwitchTime = currentTime;
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outputState = LOW;
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}
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if (outputState == LOW && (currentTime - lastSwitchTime >= offTime))
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{
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lastSwitchTime = currentTime;
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outputState = HIGH;
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}
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digitalWrite(outputPin, outputState);
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}
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