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sine wave generation in vhdl

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matt2011

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I am very new to vlsi......
I want to generate a sine wave using vhdl.
i stored all the samples in a rom and fetch one by one to generate it.my main aim is to change the phase of the sine wave for 45,90 degrees...pls help
 

treqer

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determine the frequency. In any case. to generate a sine with a frequency of 1 MHz with an accuracy of 100 points for the period necessary to touch these points at 100 megahertz.

See DDS synthesizer on FPGA

---------- Post added at 11:14 ---------- Previous post was at 11:12 ----------

jumps to address its ROM. Get an instant jump in the phase
 

BradtheRad

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To advance 90 degrees, you skip ahead ninety 360ths ( or 25 percent ) of a cycle.

The amount of samples you should skip depends on how many divisions you use per cycle.

Example, if you use 1000 divisions for a cycle, then skip ahead 250.

If your units are radians, then a full cycle is 2*Pi. The proportion is calculated the same way. 90 degrees is Pi/2 radians.
 

jimwu88

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dpaul

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I had used Taylor series expansion to generate sine & cosine waves. You can select the no. of terms to give a accurate looking waveform in the simulator!
 

jimwu88

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Check the "VHDL functions" section in this "Memory Initialization Methods" blog

I am very new to vlsi......
I want to generate a sine wave using vhdl.
i stored all the samples in a rom and fetch one by one to generate it.my main aim is to change the phase of the sine wave for 45,90 degrees...pls help
 

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