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Honored Contributor
Honored ContributorLookup Table of 12bits in VHDL
Hi all,
I need to do a lookup table of 12 bits. Can anyone help me how to do? I'm doing DDS (Direct Digital Synthesis) with Fo=10KHz and Fs=100MHz. Thanks a lot!Forum Discussion
3 Replies
Altera_ForumI assume the LUT is for a sine wave, where the amplitude is quantized to 12 bits. How many look up points do you need? If it isn't many you can build the full sine wave (1 period) in a lut array: http://stackoverflow.com/questions/21976749/design-of-a-vhdl-lut-module
If you want more resolution, you can create half period lut arrays (t = [0: pi]) or quarter period (t = [0:pi/2]) lut arrays. But then you would need more logic to infer values outside of the lut array range.- Altera_Forum
There is a direct vhdl LUT here:
http://www.alteraforum.com/forum/showthread.php?t=26594&highlight=sine+cosine+table - Altera_Forum
Thank you very much for the information.
