sine and cosine wave generation

[FPGA]

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

 

[Jon Beniston]

On 14 Jan, 15:36, FPGA <FPGA.unkn...@gmail.com> wrote:

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

Use a look-up table.

Cheers,
Jon

 

[Ralf Hildebrandt]

FPGA schrieb:

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

A very common technique is a look-up table.

Ralf

 

[FPGA]

On Jan 14, 10:43 am, Ralf Hildebrandt <Ralf-Hildebra...@gmx.de> wrote:

FPGA schrieb:

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

A very common technique is a look-up table.

Ralf

Could you please explain in more detail

 

[Kris Vorwerk]

On Jan 14, 7:47 am, FPGA <FPGA.unkn...@gmail.com> wrote:

Could you please explain in more detail

http://www.actel.com/documents/Fusion_Waveform_TB.pdf

K.

 

[comp.arch.fpga]

On 14 Jan., 16:36, FPGA <FPGA.unkn...@gmail.com> wrote:

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

You can build a numerical oscillator:

Initialization:
sin[0] = 1;
cos[0] = 0;

Iteration:
sin[t] = sin[t-1]-cos[t-1]*k;
cos[t] = cos[t-1]+sin[t-1]*k;

The Frequency depends on k. If k is 1/2**k you do not even net a
multiplier.

This only works for a continues sequence of values. If you need values
in random
order you must use a lookup table or CORDIC. Both are available as
cores in ISE.

Kolja Sulimma
cronologic ohg

 

[Symon]

"FPGA" <FPGA.unknown@gmail.com> wrote in message
news:9219f61f-678d-4ed3-801c-3a873f2a467b@k39g2000hsf.googlegroups.com...

Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

library IEEE;
use IEEE.MATH_REAL.all;
signal x,y : real;begin x <= sin;end;HTH., Syms.

 

[Arlet Ottens]

comp.arch.fpga wrote:

On 14 Jan., 16:36, FPGA <FPGA.unkn...@gmail.com> wrote:
Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

You can build a numerical oscillator:

Initialization:
sin[0] = 1;
cos[0] = 0;

Iteration:
sin[t] = sin[t-1]-cos[t-1]*k;
cos[t] = cos[t-1]+sin[t-1]*k;

The Frequency depends on k. If k is 1/2**k you do not even net a
multiplier.

This only works for a continues sequence of values. If you need values
in random
order you must use a lookup table or CORDIC. Both are available as
cores in ISE.

Kolja Sulimma
cronologic ohg

If you slightly modify the iteration, like this:

sin[t] = sin[t-1] - cos[t-1] * k;
cos[t] = cos[t-1] + sin[t] * k;

then the solution doesn't suffer from accumulating rounding errors, at
the cost of some distortion.

 

[FPGA]

On Jan 14, 1:38 pm, Arlet Ottens <usene...@c-scape.nl> wrote:

comp.arch.fpga wrote:
On 14 Jan., 16:36, FPGA <FPGA.unkn...@gmail.com> wrote:
Can anyone give guidelines on how to generate sine and cosine wave in
VHDL?

You can build a numerical oscillator:

Initialization:
sin[0] = 1;
cos[0] = 0;

Iteration:
sin[t] = sin[t-1]-cos[t-1]*k;
cos[t] = cos[t-1]+sin[t-1]*k;

The Frequency depends on k. If k is 1/2**k you do not even net a
multiplier.

This only works for a continues sequence of values. If you need values
in random
order you must use a lookup table or CORDIC. Both are available as
cores in ISE.

Kolja Sulimma
cronologic ohg

If you slightly modify the iteration, like this:

sin[t] = sin[t-1] - cos[t-1] * k;
cos[t] = cos[t-1] + sin[t] * k;

then the solution doesn't suffer from accumulating rounding errors, at
the cost of some distortion.- Hide quoted text -

- Show quoted text -

Thanks all for your help.