IEEE 802.15.4 subsystem
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| Source at commit ae1455cc7dadfaa494c792217d1e4a53efb2747e created 7 years 1 month ago. By Stefan Schmidt, atusb-eui64: print out set address with upper case characters in hex | |
|---|---|
| 1 | /* |
| 2 | * atrf-xtal/atusb.c - ATUSB-specific driver and evaluation |
| 3 | * |
| 4 | * Written 2011 by Werner Almesberger |
| 5 | * Copyright 2011 Werner Almesberger |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | */ |
| 12 | |
| 13 | |
| 14 | #include <stdlib.h> |
| 15 | #include <stdio.h> |
| 16 | #include <sys/time.h> |
| 17 | |
| 18 | #include <usb.h> |
| 19 | #include <gsl/gsl_fit.h> |
| 20 | |
| 21 | #include "at86rf230.h" |
| 22 | #include "atusb/ep0.h" |
| 23 | #include "atrf.h" |
| 24 | |
| 25 | #include "atrf-xtal.h" |
| 26 | |
| 27 | |
| 28 | #define FROM_DEV ATUSB_FROM_DEV(0) |
| 29 | |
| 30 | #define F_NOMINAL_Hz 8000000 /* nominal frequency, in Hz */ |
| 31 | |
| 32 | |
| 33 | static uint64_t get_sample(struct atrf_dsc *dsc, double *t0, double *t1) |
| 34 | { |
| 35 | struct timeval tod0, tod1; |
| 36 | uint64_t cnt; |
| 37 | int res; |
| 38 | |
| 39 | gettimeofday(&tod0, NULL); |
| 40 | res = usb_control_msg(atrf_usb_handle(dsc), |
| 41 | FROM_DEV, ATUSB_TIMER, 0, 0, (void *) &cnt, sizeof(cnt), 1000); |
| 42 | gettimeofday(&tod1, NULL); |
| 43 | if (res < 0) { |
| 44 | fprintf(stderr, "ATUSB_TIMER: %s\n", usb_strerror()); |
| 45 | exit(1); |
| 46 | } |
| 47 | *t0 = tod0.tv_sec+tod0.tv_usec/1000000.0; |
| 48 | *t1 = tod1.tv_sec+tod1.tv_usec/1000000.0; |
| 49 | return cnt; |
| 50 | } |
| 51 | |
| 52 | |
| 53 | void do_atusb(struct atrf_dsc *dsc, int trim, int dump_raw, double ppm, |
| 54 | int n) |
| 55 | { |
| 56 | double t0[n], t1[n], cnt[n], w[n]; |
| 57 | double c0, c1, cov00, cov01, cov11, chisq; |
| 58 | double d; |
| 59 | double tz = 0, cntz = 0; |
| 60 | double rel; |
| 61 | int i; |
| 62 | |
| 63 | atrf_reg_write(dsc, REG_XOSC_CTRL, |
| 64 | (XTAL_MODE_INT << XTAL_MODE_SHIFT) | trim); |
| 65 | |
| 66 | for (i = 0; i != n; i++) { |
| 67 | cnt[i] = get_sample(dsc, t0+i, t1+i); |
| 68 | if (!i) { |
| 69 | tz = t0[0]; |
| 70 | cntz = cnt[0]; |
| 71 | } |
| 72 | t0[i] -= tz; |
| 73 | t1[i] -= tz; |
| 74 | cnt[i] -= cntz; |
| 75 | |
| 76 | /* |
| 77 | * see http://en.wikipedia.org/wiki/ |
| 78 | * Uniform_distribution_(continuous) |
| 79 | */ |
| 80 | d = (t1[i]-t0[i])*F_NOMINAL_Hz; |
| 81 | w[i] = 12/(d*d); |
| 82 | } |
| 83 | |
| 84 | if (dump_raw) { |
| 85 | for (i = 0; i != n; i++) |
| 86 | printf("%.6f %.6f %.0f\n", t0[i], t1[i], cnt[i]); |
| 87 | return; |
| 88 | } |
| 89 | |
| 90 | gsl_fit_wlinear (t0, 1, w, 1, cnt, 1, n, |
| 91 | &c0, &c1, &cov00, &cov01, &cov11, &chisq); |
| 92 | |
| 93 | rel = (c1/F_NOMINAL_Hz-1)*1000000; |
| 94 | printf("%+.2f ppm", rel); |
| 95 | if (ppm && fabs(rel) > ppm) { |
| 96 | printf(" (outside bounds)\n"); |
| 97 | exit(1); |
| 98 | } |
| 99 | putchar('\n'); |
| 100 | } |
| 101 | |
