view miscprog/osmo2psi.c @ 408:14302e075f37 default tip

hr-bits: further conditionalize SID-1-diff
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 22 Jul 2024 10:06:38 +0000
parents 63c5bb42eca5
children
line wrap: on
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/*
 * This test program seeks to help figure out the mapping between OsmocomBB's
 * AFC_SLOPE constant and the Psi constants used by TI's AFC implementation,
 * as our fc-rfcal-vcxo tool would compute them from CMU200 measurements.
 */

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

main(argc, argv)
	char **argv;
{
	int afc_slope;
	float lin_a;
	float Psi_sta, Psi_st;

	if (argc != 2) {
		fprintf(stderr, "usage: %s osmo-afc-slope\n", argv[0]);
		exit(1);
	}
	afc_slope = atoi(argv[1]);
	lin_a = (float)afc_slope / 32768.0f * 898.0f;

	/* Psi computations */
	Psi_sta = 2.0f * (float)M_PI * lin_a / 270833.0f;
	Psi_st = Psi_sta * 0.8f;

	printf("Psi_sta_inv = %u\n", (unsigned)(1.0f / Psi_sta));
	printf("Psi_st = %u\n", (unsigned)(Psi_st * 65536.0f));
	printf("Psi_st_32 = %u\n", (unsigned)(Psi_st * 65536.0f * 65536.0f));
	printf("Psi_st_inv = %u\n", (unsigned)(1.0f / Psi_st));
	exit(0);
}