brainiac_rus
Newbie level 5
- Joined
- May 28, 2014
- Messages
- 10
- Helped
- 0
- Reputation
- 0
- Reaction score
- 0
- Trophy points
- 1
- Activity points
- 103
Hi all!
I tryed to calculate a value of sine and cosine functions using cordic algorithm. But it does not work in fixed point system and i wrote it as simple program.
Here is a code:
But it does not work again.
I use this article as source http://andraka.com/files/crdcsrvy.pdf
What is wrong in my code? I think there are some stupied errors, but i can't find it.
this is what i see in console
I tryed to calculate a value of sine and cosine functions using cordic algorithm. But it does not work in fixed point system and i wrote it as simple program.
Here is a code:
Code:
module cordic_test0(
);
real cordic_iter[15:0];
real angle;
integer i = 0;
real xi;
real yi;
real zi;
initial begin
cordic_iter[0] = 45.0;
cordic_iter[1] = 26.56505118;
cordic_iter[2] = 14.03624347;
cordic_iter[3] = 7.125016349;
cordic_iter[4] = 3.576334375;
cordic_iter[5] = 1.789910608;
cordic_iter[6] = 0.89517371;
cordic_iter[7] = 0.447614171;
cordic_iter[8] = 0.2238105;
cordic_iter[9] = 0.111905677;
cordic_iter[10] = 0.055952892;
cordic_iter[11] = 0.027976453;
cordic_iter[12] = 0.013988227;
cordic_iter[13] = 0.006994114;
cordic_iter[14] = 0.003497057;
cordic_iter[15] = 0.001748528;
#100;
angle = 45.0;
zi = angle;
xi = 0.6071;
yi = 0.0;
for(i = 0; i < 16; i = i + 1)
begin
if(zi > 0)
begin
zi = zi - cordic_iter[i];
xi = xi - (yi / 2.0**i);//cos
yi = yi + (xi / 2.0**i);//sin
end
else
begin
zi = zi + cordic_iter[i];
xi = xi + (yi / 2.0**i);
yi = yi - (xi / 2.0**i);
end
$display(i," ", zi);
$display(xi," ", yi);
end
$display("Cos angle is ", xi);
$display("Sin angle is ", yi);
$display("Cos angle is ", xi*0.6071);
$display("Sin angle is ", yi*0.6071);
#100;
$stop;
end
endmoduleBut it does not work again.
I use this article as source http://andraka.com/files/crdcsrvy.pdf
What is wrong in my code? I think there are some stupied errors, but i can't find it.
this is what i see in console
Code:
0 0
0.6071 0.6071
1 26.5651
0.91065 0.151775
2 12.5288
0.872706 0.369952
3 5.40379
0.826462 0.473259
4 1.82746
0.796884 0.523065
5 0.0375464
0.780538 0.547456
6 -0.857627
0.771984 0.559519
7 -0.410013
0.776355 0.553453
8 -0.186203
0.778517 0.550412
9 -0.074297
0.779592 0.54889
10 -0.0183441
0.780128 0.548128
11 0.00963236
0.780396 0.547747
12 -0.00435587
0.780262 0.547937
13 0.00263825
0.780329 0.547842
14 -0.000858809
0.780295 0.54789
15 0.000889719
0.780312 0.547866
Cos angle is 0.780312
Sin angle is 0.547866
Cos angle is 0.473727
Sin angle is 0.332609