comparison rfcal/vcxo-manual/genparams.c @ 182:9099a35a705f

manual VCXO calibration code: fc-vcxo-param utility written
author Mychaela Falconia <falcon@freecalypso.org>
date Wed, 12 Apr 2017 07:33:38 +0000
parents
children b8599a1d5813
comparison
equal deleted inserted replaced
181:dcab0be3f67a 182:9099a35a705f
1 #include <math.h>
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include "meas.h"
5
6 struct meas meas[4];
7 float lin_a, lin_b, lin_a2, lin_b2;
8 float dac_min, dac_max, dac_init;
9 float Psi_sta, Psi_st;
10
11 write_output(filename)
12 char *filename;
13 {
14 FILE *outf;
15
16 if (filename) {
17 outf = fopen(filename, "w");
18 if (!outf) {
19 perror(filename);
20 exit(1);
21 }
22 } else
23 outf = stdout;
24
25 fputs("rf_table afcparams\n\n", outf);
26 /* Psi parameters */
27 fprintf(outf, "%10u\t# Psi_sta_inv\n", (unsigned)(1.0f / Psi_sta));
28 fprintf(outf, "%10u\t# Psi_st\n", (unsigned)(Psi_st * 65536.0f));
29 fprintf(outf, "%10u\t# Psi_st_32\n",
30 (unsigned)(Psi_st * 65536.0f * 65536.0f));
31 fprintf(outf, "%10u\t# Psi_st_inv\n\n", (unsigned)(1.0f / Psi_st));
32 /* DAC settings */
33 fprintf(outf, "%10d\t# DAC_INIT * 8\n", (int)(dac_init * 8.0f));
34 fprintf(outf, "%10d\t# DAC_MIN * 8\n", (int)(dac_min * 8.0f));
35 fprintf(outf, "%10d\t# DAC_MAX * 8\n", (int)(dac_max * 8.0f));
36 fprintf(outf, "%10d\t# snr_thr\n", 2560);
37 /* rfpw 10 setting in a comment line */
38 fprintf(outf, "\n# DAC_INIT: rfpw 10 %d\n", (int)dac_init);
39
40 if (filename)
41 fclose(outf);
42 }
43
44 main(argc, argv)
45 char **argv;
46 {
47 float pi;
48
49 if (argc < 2 || argc > 3) {
50 fprintf(stderr, "usage: %s meas-file [outfile]\n", argv[0]);
51 exit(1);
52 }
53 read_meas_file(argv[1], meas, 4);
54
55 /* first linear approximation */
56 lin_a = (float)(meas[1].freq_offset - meas[0].freq_offset) /
57 (float)(meas[1].dac_value - meas[0].dac_value);
58 lin_b = (float)meas[1].freq_offset - lin_a * meas[1].dac_value;
59
60 /* second linear approximation */
61 lin_a2 = (float)(meas[3].freq_offset - meas[2].freq_offset) /
62 (float)(meas[3].dac_value - meas[2].dac_value);
63 lin_b2 = (float)meas[3].freq_offset - lin_a * meas[2].dac_value;
64
65 /* DAC settings */
66 dac_min = (-13500.0f - lin_b) / lin_a;
67 dac_max = (13500.0f - lin_b) / lin_a;
68 dac_init = -lin_b2 / lin_a2;
69
70 /* Psi computations */
71 pi = acos(-1.0);
72 Psi_sta = 2.0f * pi * (float)(meas[1].freq_offset - meas[0].freq_offset)
73 / ((float)(meas[1].dac_value - meas[0].dac_value) * 270833.0f);
74 Psi_st = Psi_sta * 0.8f;
75
76 /* spit it all out */
77 write_output(argv[2]);
78 exit(0);
79 }