#include #include #include uint32_t g_goertzel_omega_per_sample; int32_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() { //XXX XXX NOTE If you are computing the coefficients, you can plug the value in here. g_goertzel_omega_per_sample = (47.0/256) * 3.1415926535*2.0*(1<<29); g_goertzel_coefficient = 2 * cos( g_goertzel_omega_per_sample / (double)(1<<29) ) * (1<<30); g_goertzel_coefficient_s = 2 * sin( g_goertzel_omega_per_sample / (double)(1<<29) ) * (1<<30); const double AomegaPerSample = g_goertzel_omega_per_sample/(double)(1<<29); const int AnumSamples = 256; // enough to go from 0 to 2pi double Acoeff = 2 * cos( AomegaPerSample ) * 65536; double Acoeff_s = 2 * sin( AomegaPerSample ) * 65536; double Asprev = AomegaPerSample * 65536; double Asprev2 = 0; printf( "%d / %d / %d %f / %f / %f\n", g_goertzel_omega_per_sample, g_goertzel_coefficient, g_goertzel_coefficient_s, Acoeff, Acoeff_s, AomegaPerSample ); g_goertzelp = g_goertzel_omega_per_sample>>(29-16); 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; double As; int js = 0; for( js = 0; js < 260/4; 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( AomegaPerSample * (x+js*4) ) * 16384*0; \ \ /* Fixed */ \ goertzel = t + ( ( (((int32_t)(goertzel_coefficient))) * ((((int64_t)goertzelp)<<2)) ) >> 32 ) - goertzelp2; \ goertzelp2 = goertzelp; \ goertzelp = goertzel; \ \ /* Float */ \ As = t + ( Acoeff * Asprev ) / 65536.0 - Asprev2; \ Asprev2 = Asprev; \ Asprev = As; \ \ /*printf( "%d,%d,%d,%d\n", ( ( (int64_t)(goertzel_coefficient) * (int64_t)goertzelp ) >> 32 ) , goertzel_coefficient, goertzelp, goertzelp2 ); */ \ \ {\ int32_t rr = (((int64_t)(g_goertzel_coefficient ) * (int64_t)goertzelp<<1)>>32) - (goertzelp2); \ int32_t ri = (((int64_t)(g_goertzel_coefficient_s) * (int64_t)goertzelp<<1)>>32); \ /*printf( "%3d %10d %10d %10d %10d / %9d %9d %9d * ", js*4+x, rr, ri, goertzelp, goertzelp2, goertzel_coefficient, g_goertzel_omega_per_sample, t );*/ \ /*printf( "%4d %10d %10d (%10d %10d) ", js*4+x, goertzelp, goertzelp2, goertzel_coefficient, g_goertzel_coefficient_s );*/ \ printf( "%4d %10d %10d (%10d %10d) ", js*4+x, goertzelp, goertzelp2, rr, ri ); \ \ float Apower = Asprev*Asprev + Asprev2*Asprev2 - (Acoeff * Asprev * Asprev2); \ double ArR = 0.5 * Acoeff * Asprev / 65536 - Asprev2; \ double ArI = 0.5 * Acoeff_s * Asprev / 65536; \ /*printf( "%14.3f, %14.3f (%14.3f %14.3f)\n", Asprev, Asprev2, Acoeff,Acoeff_s );*/ \ printf( "%14.3f, %14.3f (%14.3f %14.3f %f)\n", Asprev, Asprev2, ArR, ArI, sqrt( ArR*ArR +ArI*ArI ) ); \ } 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; printf( "Constants:\nconst int32_t g_goertzel_omega_per_sample = %d;\nconst int32_t g_goertzel_coefficient = %d;\nconst int32_t g_goertzel_coefficient_s = %d;\n", g_goertzel_omega_per_sample, g_goertzel_coefficient, g_goertzel_coefficient_s ); }