+++ /dev/null
-/*
- * rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
- * Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
- * Copyright (C) 2012 by Hoernchen <la@tfc-server.de>
- * Copyright (C) 2012 by Kyle Keen <keenerd@gmail.com>
- * Copyright (C) 2012 by Youssef Touil <youssef@sdrsharp.com>
- * Copyright (C) 2012 by Ian Gilmour <ian@sdrsharp.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-
-#include <errno.h>
-#include <signal.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
-
-#ifndef _WIN32
-#include <unistd.h>
-#else
-#include <Windows.h>
-#include <fcntl.h>
-#include <io.h>
-#include "getopt/getopt.h"
-#endif
-
-#include <semaphore.h>
-#include <pthread.h>
-#include <libusb.h>
-
-#include "rtl-sdr.h"
-
-#ifdef _WIN32
-#define sleep Sleep
-#define round(x) (x > 0.0 ? floor(x + 0.5): ceil(x - 0.5))
-#endif
-
-#define ADSB_RATE 2000000
-#define ADSB_FREQ 1090000000
-#define DEFAULT_ASYNC_BUF_NUMBER 12
-#define DEFAULT_BUF_LENGTH (16 * 16384)
-#define AUTO_GAIN -100
-
-static pthread_t demod_thread;
-static sem_t data_ready;
-static volatile int do_exit = 0;
-static rtlsdr_dev_t *dev = NULL;
-
-/* look up table, could be made smaller */
-uint8_t pyth[129][129];
-
-/* todo, bundle these up in a struct */
-uint8_t *buffer;
-int verbose_output = 0;
-int short_output = 0;
-double quality = 1.0;
-int allowed_errors = 5;
-FILE *file;
-int adsb_frame[14];
-#define preamble_len 16
-#define long_frame 112
-#define short_frame 56
-
-void usage(void)
-{
- fprintf(stderr,
- "rtl_adsb, a simple ADS-B decoder\n\n"
- "Use:\trtl_adsb [-R] [-g gain] [-p ppm] [output file]\n"
- "\t[-d device_index (default: 0)]\n"
- "\t[-V verbove output (default: off)]\n"
- "\t[-S show short frames (default: off)]\n"
- "\t[-Q quality (0: no sanity checks, 0.5: half bit, 1: one bit (default), 2: two bits)]\n"
- "\t[-e allowed_errors (default: 5)]\n"
- "\t[-g tuner_gain (default: automatic)]\n"
- "\t[-p ppm_error (default: 0)]\n"
- "\tfilename (a '-' dumps samples to stdout)\n"
- "\t (omitting the filename also uses stdout)\n\n"
- "Streaming with netcat:\n"
- "\trtl_adsb | netcat -lp 8080\n"
- "\twhile true; do rtl_adsb | nc -lp 8080; done\n"
- "Streaming with socat:\n"
- "\trtl_adsb | socat -u - TCP4:sdrsharp.com:47806\n"
- "\n");
- exit(1);
-}
-
-#ifdef _WIN32
-BOOL WINAPI
-sighandler(int signum)
-{
- if (CTRL_C_EVENT == signum) {
- fprintf(stderr, "Signal caught, exiting!\n");
- do_exit = 1;
- rtlsdr_cancel_async(dev);
- return TRUE;
- }
- return FALSE;
-}
-#else
-static void sighandler(int signum)
-{
- fprintf(stderr, "Signal caught, exiting!\n");
- do_exit = 1;
- rtlsdr_cancel_async(dev);
-}
-#endif
-
-void display(int *frame, int len)
-{
- int i, df;
- if (!short_output && len <= short_frame) {
- return;}
- df = (frame[0] >> 3) & 0x1f;
- if (quality == 0.0 && !(df==11 || df==17 || df==18 || df==19)) {
- return;}
- fprintf(file, "*");
- for (i=0; i<((len+7)/8); i++) {
- fprintf(file, "%02x", frame[i]);}
- fprintf(file, ";\r\n");
- if (!verbose_output) {
- return;}
- fprintf(file, "DF=%i CA=%i\n", df, frame[0] & 0x07);
- fprintf(file, "ICAO Address=%06x\n", frame[1] << 16 | frame[2] << 8 | frame[3]);
- if (len <= short_frame) {
- return;}
- fprintf(file, "PI=0x%06x\n", frame[11] << 16 | frame[12] << 8 | frame[13]);
- fprintf(file, "Type Code=%i S.Type/Ant.=%x\n", (frame[4] >> 3) & 0x1f, frame[4] & 0x07);
- fprintf(file, "--------------\n");
-}
-
-void pyth_precompute(void)
-{
- int x, y;
- double scale = 1.408 ; /* use the full 8 bits */
- for (x=0; x<129; x++) {
- for (y=0; y<129; y++) {
- pyth[x][y] = (uint8_t)round(scale * sqrt(x*x + y*y));
- }}
-}
-
-inline uint8_t abs8(uint8_t x)
-/* do not subtract 128 from the raw iq, this handles it */
-{
- if (x >= 128) {
- return x - 128;}
- return 128 - x;
-}
-
-int magnitute(uint8_t *buf, int len)
-/* takes i/q, changes buf in place, returns new len */
-{
- int i;
- for (i=0; i<len; i+=2) {
- buf[i/2] = pyth[abs8(buf[i])][abs8(buf[i+1])];
- }
- return len/2;
-}
-
-inline uint8_t single_manchester(uint8_t a, uint8_t b, uint8_t c, uint8_t d)
-/* takes 4 consecutive real samples, return 0 or 1, 255 on error */
-{
- int bit, bit_p;
- bit_p = a > b;
- bit = c > d;
-
- if (quality == 0.0) {
- return bit;}
-
- if (quality == 0.5) {
- if ( bit && bit_p && b > c) {
- return 255;}
- if (!bit && !bit_p && b < c) {
- return 255;}
- return bit;
- }
-
- if (quality == 1.0) {
- if ( bit && bit_p && c > b) {
- return 1;}
- if ( bit && !bit_p && d < b) {
- return 1;}
- if (!bit && bit_p && d > b) {
- return 0;}
- if (!bit && !bit_p && c < b) {
- return 0;}
- return 255;
- }
-
- if ( bit && bit_p && c > b && d < a) {
- return 1;}
- if ( bit && !bit_p && c > a && d < b) {
- return 1;}
- if (!bit && bit_p && c < a && d > b) {
- return 0;}
- if (!bit && !bit_p && c < b && d > a) {
- return 0;}
- return 255;
-}
-
-inline uint8_t min8(uint8_t a, uint8_t b)
-{
- return a<b ? a : b;
-}
-
-inline uint8_t max8(uint8_t a, uint8_t b)
-{
- return a>b ? a : b;
-}
-
-inline int preamble(uint8_t *buf, int len, int i)
-/* returns 0/1 for preamble at index i */
-{
- int i2;
- uint8_t low = 0;
- uint8_t high = 255;
- for (i2=0; i2<preamble_len; i2++) {
- switch (i2) {
- case 0:
- case 2:
- case 7:
- case 9:
- //high = min8(high, buf[i+i2]);
- high = buf[i+i2];
- break;
- default:
- //low = max8(low, buf[i+i2]);
- low = buf[i+i2];
- break;
- }
- if (high <= low) {
- return 0;}
- }
- return 1;
-}
-
-void manchester(uint8_t *buf, int len)
-/* overwrites magnitude buffer with valid bits (255 on errors) */
-{
- /* a and b hold old values to verify local manchester */
- uint8_t a=0, b=0;
- uint8_t bit;
- int i, i2, start, errors;
- // todo, allow wrap across buffers
- i = 0;
- while (i < len) {
- /* find preamble */
- for ( ; i < (len - preamble_len); i++) {
- if (!preamble(buf, len, i)) {
- continue;}
- a = buf[i];
- b = buf[i+1];
- for (i2=0; i2<preamble_len; i2++) {
- buf[i+i2] = 253;}
- i += preamble_len;
- break;
- }
- i2 = start = i;
- errors = 0;
- /* mark bits until encoding breaks */
- for ( ; i < len; i+=2, i2++) {
- bit = single_manchester(a, b, buf[i], buf[i+1]);
- a = buf[i];
- b = buf[i+1];
- if (bit == 255) {
- errors += 1;
- if (errors > allowed_errors) {
- buf[i2] = 255;
- break;
- } else {
- bit = a > b;
- /* these don't have to match the bit */
- a = 0;
- b = 255;
- }
- }
- buf[i] = buf[i+1] = 254; /* to be overwritten */
- buf[i2] = bit;
- }
- }
-}
-
-void messages(uint8_t *buf, int len)
-{
- int i, i2, start, preamble_found;
- int data_i, index, shift, frame_len;
- // todo, allow wrap across buffers
- for (i=0; i<len; i++) {
- if (buf[i] > 1) {
- continue;}
- frame_len = long_frame;
- data_i = 0;
- for (index=0; index<14; index++) {
- adsb_frame[index] = 0;}
- for(; i<len && buf[i]<=1 && data_i<frame_len; i++, data_i++) {
- if (buf[i]) {
- index = data_i / 8;
- shift = 7 - (data_i % 8);
- adsb_frame[index] |= (uint8_t)(1<<shift);
- }
- if (data_i == 7) {
- if (adsb_frame[0] == 0) {
- break;}
- if (adsb_frame[0] & 0x80) {
- frame_len = long_frame;}
- else {
- frame_len = short_frame;}
- }
- }
- if (data_i < (frame_len-1)) {
- continue;}
- display(adsb_frame, frame_len);
- fflush(file);
- }
-}
-
-static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
-{
- int dr_val;
- if (do_exit) {
- return;}
- memcpy(buffer, buf, len);
- sem_getvalue(&data_ready, &dr_val);
- if (dr_val <= 0) {
- sem_post(&data_ready);}
-}
-
-static void *demod_thread_fn(void *arg)
-{
- int len;
- while (!do_exit) {
- sem_wait(&data_ready);
- len = magnitute(buffer, DEFAULT_BUF_LENGTH);
- manchester(buffer, len);
- messages(buffer, len);
- }
- rtlsdr_cancel_async(dev);
- return 0;
-}
-
-int main(int argc, char **argv)
-{
-#ifndef _WIN32
- struct sigaction sigact;
-#endif
- char *filename = NULL;
- int n_read, r, opt;
- int i, gain = AUTO_GAIN; /* tenths of a dB */
- uint32_t dev_index = 0;
- int device_count;
- int ppm_error = 0;
- char vendor[256], product[256], serial[256];
- sem_init(&data_ready, 0, 0);
- pyth_precompute();
-
- while ((opt = getopt(argc, argv, "d:g:p:e:Q:VS")) != -1)
- {
- switch (opt) {
- case 'd':
- dev_index = atoi(optarg);
- break;
- case 'g':
- gain = (int)(atof(optarg) * 10);
- break;
- case 'p':
- ppm_error = atoi(optarg);
- break;
- case 'V':
- verbose_output = 1;
- break;
- case 'S':
- short_output = 1;
- break;
- case 'e':
- allowed_errors = atoi(optarg);
- break;
- case 'Q':
- quality = atof(optarg);
- break;
- default:
- usage();
- return 0;
- }
- }
-
- if (argc <= optind) {
- filename = "-";
- } else {
- filename = argv[optind];
- }
-
- buffer = malloc(DEFAULT_BUF_LENGTH * sizeof(uint8_t));
-
- device_count = rtlsdr_get_device_count();
- if (!device_count) {
- fprintf(stderr, "No supported devices found.\n");
- exit(1);
- }
-
- fprintf(stderr, "Found %d device(s):\n", device_count);
- for (i = 0; i < device_count; i++) {
- rtlsdr_get_device_usb_strings(i, vendor, product, serial);
- fprintf(stderr, " %d: %s, %s, SN: %s\n", i, vendor, product, serial);
- }
- fprintf(stderr, "\n");
-
- fprintf(stderr, "Using device %d: %s\n",
- dev_index, rtlsdr_get_device_name(dev_index));
-
- r = rtlsdr_open(&dev, dev_index);
- if (r < 0) {
- fprintf(stderr, "Failed to open rtlsdr device #%d.\n", dev_index);
- exit(1);
- }
-#ifndef _WIN32
- sigact.sa_handler = sighandler;
- sigemptyset(&sigact.sa_mask);
- sigact.sa_flags = 0;
- sigaction(SIGINT, &sigact, NULL);
- sigaction(SIGTERM, &sigact, NULL);
- sigaction(SIGQUIT, &sigact, NULL);
- sigaction(SIGPIPE, &sigact, NULL);
-#else
- SetConsoleCtrlHandler( (PHANDLER_ROUTINE) sighandler, TRUE );
-#endif
-
- if (strcmp(filename, "-") == 0) { /* Write samples to stdout */
- file = stdout;
- setvbuf(stdout, NULL, _IONBF, 0);
-#ifdef _WIN32
- _setmode(_fileno(file), _O_BINARY);
-#endif
- } else {
- file = fopen(filename, "wb");
- if (!file) {
- fprintf(stderr, "Failed to open %s\n", filename);
- exit(1);
- }
- }
-
- /* Set the tuner gain */
- if (gain == AUTO_GAIN) {
- r = rtlsdr_set_tuner_gain_mode(dev, 0);
- } else {
- r = rtlsdr_set_tuner_gain_mode(dev, 1);
- r = rtlsdr_set_tuner_gain(dev, gain);
- }
- if (r != 0) {
- fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
- } else if (gain == AUTO_GAIN) {
- fprintf(stderr, "Tuner gain set to automatic.\n");
- } else {
- fprintf(stderr, "Tuner gain set to %0.2f dB.\n", gain/10.0);
- }
-
- r = rtlsdr_set_freq_correction(dev, ppm_error);
- r = rtlsdr_set_agc_mode(dev, 1);
-
- /* Set the tuner frequency */
- r = rtlsdr_set_center_freq(dev, ADSB_FREQ);
- if (r < 0) {
- fprintf(stderr, "WARNING: Failed to set center freq.\n");}
- else {
- fprintf(stderr, "Tuned to %u Hz.\n", ADSB_FREQ);}
-
- /* Set the sample rate */
- fprintf(stderr, "Sampling at %u Hz.\n", ADSB_RATE);
- r = rtlsdr_set_sample_rate(dev, ADSB_RATE);
- if (r < 0) {
- fprintf(stderr, "WARNING: Failed to set sample rate.\n");}
-
- /* Reset endpoint before we start reading from it (mandatory) */
- r = rtlsdr_reset_buffer(dev);
- if (r < 0) {
- fprintf(stderr, "WARNING: Failed to reset buffers.\n");}
-
- /* flush old junk */
- sleep(1);
- rtlsdr_read_sync(dev, NULL, 4096, NULL);
-
- pthread_create(&demod_thread, NULL, demod_thread_fn, (void *)(NULL));
- rtlsdr_read_async(dev, rtlsdr_callback, (void *)(NULL),
- DEFAULT_ASYNC_BUF_NUMBER,
- DEFAULT_BUF_LENGTH);
-
-
- if (do_exit) {
- fprintf(stderr, "\nUser cancel, exiting...\n");}
- else {
- fprintf(stderr, "\nLibrary error %d, exiting...\n", r);}
- rtlsdr_cancel_async(dev);
-
- if (file != stdout) {
- fclose(file);}
-
- rtlsdr_close(dev);
- free(buffer);
- return r >= 0 ? r : -r;
-}
-
projects / rtl-433.git / blobdiff