Welcome to Arduino-Atmel-sPWM Discussions!

[Irev-Dev]

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[gjvengu]

Hello Sir

[Ronald101101]

Can i generate 1khz sine wave using this if so how?

[Irev-Dev]

From memory the switching frequency is about 20khz, so it would only be 20 pulses per cycle which is probably too few/course.

Have you watched the video? https://www.youtube.com/watch?v=Pf2Jx5LMXH0
Might give you a better idea of what would need to change to get a decent 1khz wave.

Bare in mind arduinos have 16mhz crystal, which is not terribly fast.

[T31328]

Hello Sir
I am having an issue understanding the code for switching frequency and how to increase the switching frequency. Kindly help me to understand the formula given in the code for the period and its relation with Switching frequency.

[Irev-Dev]

Sorry mate, your question is very vague, hard to know where to start. Is there anything specific you don't understand about the code?

And for completeness's sake, Are you aware there are videos on youtube explaining the code?
https://www.youtube.com/watch?v=Pf2Jx5LMXH0

[T31328]

Yes, Sir, I have watched the video. My question is simply related to the Switching frequency how can I increase the switching frequency by using this code? Secondly, there is a period calculated in this code what is that period related with the switching frequency

[ProgArtDaVinci]

The last code of the interrupt service program in the article does not work correctly. After lookUp[99]-A, lookUp[0]-A is performed. And then the channel is switched to B and lookUp[1]-B is performed. LookUp[0]-B is skipped. Further, such a defect also occurs with channel A. And this can be seen on the oscilloscope in practice. Redundant signal.
I suggest a simpler code:

ISR( TIMER1_OVF_vect ) {
	static int num;
	if( num >= SinDivisions/2 )
	{
		TCCR1A ^= 0b10100000;	// Toggle connect and disconnect of compare output A and B.
		num = 0;                // Reset num
	}
	OCR1A = lookUp[ num ];
	OCR1B = lookUp[ num ];
	num++;
}