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cnlohr
2024-06-23 01:10:57 -04:00
parent 9bbca912a0
commit 17b7d3fdcb
2 changed files with 189 additions and 23 deletions
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ch32v/ch32v203-fft/goertzel/ttest/ttest.c
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#include <stdio.h>
#include <math.h>
#include <stdint.h>
uint32_t g_goertzel_omega_per_sample;
uint32_t g_goertzel_coefficient;
int32_t g_goertzel_coefficient_s;
uint32_t g_goertzel_samples;
uint32_t g_goertzel_outs;
int32_t g_goertzelp, g_goertzelp2;
int32_t g_goertzelp_store, g_goertzelp2_store;
int main()
{
g_goertzel_omega_per_sample = 1.0/128 * 3.14159*2.0*65536;
g_goertzel_coefficient = 2 * cos( g_goertzel_omega_per_sample / 65536.0 ) * 65536;
g_goertzel_coefficient_s = 2 * sin( g_goertzel_omega_per_sample / 65536.0 ) * 65536;
g_goertzelp = g_goertzel_omega_per_sample;
int32_t goertzel_coefficient = g_goertzel_coefficient;
int32_t goertzelp2 = g_goertzelp2;
int32_t goertzelp = g_goertzelp;
uint32_t goertzel_samples = g_goertzel_samples;
uint32_t adc_tail;
int js = 0;
for( js = 0; js < 256/4; js++ )
{
int32_t t; // 1/2 of 4096, to try to keep our numbers reasonable.
// Here is where the magic happens.
int32_t goertzel;
#define ITERATION(x) \
t = sin( (x+js*4) ) * 65536; \
goertzel = t + ( ( (int64_t)(goertzel_coefficient) * goertzelp ) >> 16 ) - goertzelp2; \
goertzelp2 = goertzelp; \
goertzelp = goertzel; \
\
/*printf( "%d,%d,%d,%d\n", ( ( (int64_t)(goertzel_coefficient) * (int64_t)goertzelp ) >> 32 ) , goertzel_coefficient, goertzelp, goertzelp2 ); */ \
\
{\
float coeff_s = /* 2 * sin( g_goertzel_omega_per_sample/65536.0f ); */ 65536; \
int32_t rr = ((g_goertzel_coefficient/2 * (int64_t)goertzelp)>>16) - g_goertzelp2; \
int32_t ri = ((g_goertzel_coefficient_s/2 * (int64_t)goertzelp)>>16); \
printf( "%3d %9d %9d %9d %9d / %9d %9d %9d\n", js, rr, ri, goertzelp, goertzelp2, goertzel_coefficient, g_goertzel_omega_per_sample, t ); \
}
ITERATION( 0 );
ITERATION( 1 );
ITERATION( 2 );
ITERATION( 3 );
adc_tail+=4;
goertzel_samples+=4;
// if( adc_tail == adc_buffer_top ) adc_tail = adc_buffer;
if( goertzel_samples == 128 )
{
g_goertzelp_store = goertzelp;
g_goertzelp2_store = goertzelp2;
goertzelp = 0;
goertzelp2 = 0;
g_goertzel_outs++;
goertzel_samples = 0;
}
}
g_goertzelp2 = goertzelp2;
g_goertzelp = goertzelp;
g_goertzel_samples = goertzel_samples;
}