Hi,
I'm trying to use DPI-C to import sin function, but it doesn't work, as a workround i had used a sin approximative function which finally give a static value of 2.5 (the offset value) i think that the instanciation of the sin in the code does not work, and i did not know why, any help would be appreciable:
package math_pkg;
//import dpi task C Name = SV function name
//import "DPI-C" pure function real sin (input real rTheta);
`define PI 3.14159265
function real sin;
input x;
real x;
real x1,y,y2,y3,y5,y7,sum,sign;
begin
sign = 1.0;
x1 = x;
if (x1<0)
begin
x1 = -x1;
sign = -1.0;
end
while (x1 > `PI/2.0)
begin
x1 = x1 - `PI;
sign = -1.0*sign;
end
y = x1*2/`PI;
y2 = y*y;
y3 = y*y2;
y5 = y3*y2;
y7 = y5*y2;
sum = 1.570794*y - 0.645962*y3 +
0.079692*y5 - 0.004681712*y7;
sin = sign*sum;
end
endfunction // sin
endpackage : math_pkg
module sv_ams_sin_voltage_gen(output real sine_out);
import math_pkg::*;
parameter sampling_time = 5;
const real pi = 3.1416;
real time_us, time_s ;
bit sampling_clock;
real freq = 20;
real offset = 2.5;
real ampl = 2.5;
always sampling_clock = #(sampling_time) ~sampling_clock;
always @(sampling_clock) begin
time_us = $time/1000;
time_s = time_us/1000000;
end
assign sine_out = offset + (ampl * sin(2*pi*freq));
endmodule