int
main(int argc, char **argv)
{
int i, p, act;
struct hardware hw;
if (set_mode(0, NULL, NULL)) {
cleanup();
return 0;
}
(void)read_hardware_parameters("hardware.txt", &hw);
/* get our own copy, error handling in set_mode() */
printf("%i\n", (int)(hw.freq * hw.min_len / 100));
for (i = act = 0;; i++) {
p = get_pulse();
if (p & GETBIT_IO) {
printf("IO error!\n");
break;
}
act += p;
printf("%c", p == 1 ? '+' : ' ');
if (i == (int)(hw.freq * hw.min_len / 100)) {
printf(" %lu\n", act*hw.freq/hw.min_len);
i = act = 0;
}
(void)usleep(1000000.0 / hw.freq);
}
cleanup();
return 0;
}
int main(int argc, char **argv)
{
struct tap tapin, tapout;
FILE *infile;
long pulse;
getopts(argc, argv);
if (optind == argc) {
infile = stdin;
} else if (optind == argc - 1) {
if (!strcmp(argv[optind], "-")) {
infile = stdin;
} else {
infile = fopen(argv[optind], "rb");
if (!infile) {
perror(argv[optind]);
return 1;
}
}
} else {
fprintf(stderr, "%s: too many arguments\n", argv0);
usage();
return 1;
}
if (tap_read_header(&tapin, infile)) {
fprintf(stderr, "%s: error reading TAP file\n", argv0);
return 1;
}
if (outversion < 0) tapout.version = tapin.version;
else tapout.version = outversion;
if (tap_write_header(&tapout, stdout)) {
fprintf(stderr, "%s: error writing TAP file\n", argv0);
return 1;
}
while ((pulse = get_pulse(&tapin)) >= 0) {
if (tapin.version == 0 &&
pulse == V0_LONG_PULSE) {
pulse = LONG_PULSE;
}
pulse /= speed;
put_pulse(pulse, &tapout);
}
tap_close(&tapout);
return 0;
}
/*
* The bits are decoded from the signal using an exponential low-pass filter in
* conjunction with a Schmitt trigger. The idea and the initial implementation
* for this come from Udo Klein, with permission.
* http://blog.blinkenlight.net/experiments/dcf77/binary-clock/#comment-5916
*/
struct GB_result
get_bit_live(void)
{
char outch;
bool newminute = false;
unsigned stv = 1;
int p;
struct timespec slp;
#if !defined(MACOS)
struct timespec tp0, tp1;
#endif
unsigned sec2;
long long a, y = 1000000000;
long long twait;
static int init_bit = 2;
bool is_eom = gb_res.marker == emark_minute ||
gb_res.marker == emark_late;
bit.freq_reset = false;
bit.bitlen_reset = false;
set_new_state();
/*
* One period is either 1000 ms or 2000 ms long (normal or padding for
* last). The active part is either 100 ms ('0') or 200 ms ('1') long.
* The maximum allowed values as percentage of the second length are
* specified as half the value and the whole value of the lengths of
* bit 0 and bit 20 respectively.
*
* ~A > 3/2 * realfreq: end-of-minute
* ~A > 5/2 * realfreq: timeout
*/
if (init_bit == 2) {
bit.realfreq = hw.freq * 1000000;
bit.bit0 = bit.realfreq / 10;
bit.bit20 = bit.realfreq / 5;
}
sec2 = 1000000000 / (hw.freq * hw.freq);
/*
* Set up filter, reach 50% after realfreq/20 samples (i.e. 50 ms)
*/
a = 1000000000 - (long long)(1000000000 * exp2(-2e7 / bit.realfreq));
bit.tlow = -1;
bit.tlast0 = -1;
for (bit.t = 0; bit.t != 0xFFFFFFFF; bit.t++) {
#if !defined(MACOS)
(void)clock_gettime(CLOCK_MONOTONIC, &tp0);
#endif
p = get_pulse();
if (p == 2) {
gb_res.bad_io = true;
outch = '*';
goto report;
}
if (bit.signal != NULL) {
if ((bit.t & 7) == 0)
bit.signal[bit.t / 8] = 0;
/* clear data from previous second */
bit.signal[bit.t / 8] |= p << (unsigned char)(bit.t & 7);
}
if (y >= 0 && y < a / 2)
bit.tlast0 = (int)bit.t;
y += a * (p * 1000000000 - y) / 1000000000;
/*
* Prevent algorithm collapse during thunderstorms
* or scheduler abuse
*/
if (bit.realfreq <= hw.freq * 500000 ||
bit.realfreq >= hw.freq * 1500000)
reset_frequency();
if (bit.t > bit.realfreq * 2500000) {
bit.realfreq += ((long long)
(bit.t * 2500000 - bit.realfreq) / 20);
a = 1000000000 - (long long)(1000000000 *
exp2(-2e7 / bit.realfreq));
if (bit.tlow * 100 / bit.t < 1) {
gb_res.hwstat = ehw_receive;
outch = 'r';
} else if (bit.tlow * 100 / bit.t >= 99) {
gb_res.hwstat = ehw_transmit;
outch = 'x';
} else {
gb_res.hwstat = ehw_random;
outch = '#';
}
goto report; /* timeout */
}
/*
* Schmitt trigger, maximize value to introduce
* hysteresis and to avoid infinite memory.
*/
if (y < 500000000 && stv == 1) {
/* end of high part of second */
y = 0;
stv = 0;
bit.tlow = (int)bit.t;
}
if (y > 500000000 && stv == 0) {
/* end of low part of second */
y = 1000000000;
stv = 1;
newminute = bit.t * 2000000 > bit.realfreq * 3;
if (init_bit == 2)
init_bit--;
else {
if (newminute)
bit.realfreq += ((long long)(bit.t *
500000 - bit.realfreq) / 20);
else
bit.realfreq += ((long long)(bit.t *
1000000 - bit.realfreq) / 20);
a = 1000000000 - (long long)(1000000000 *
exp2(-2e7 / bit.realfreq));
}
if (newminute) {
/*
* Reset the frequency and the EOM flag if two
* consecutive EOM markers come in, which means
* something is wrong.
*/
if (is_eom) {
if (gb_res.marker == emark_minute)
gb_res.marker = emark_none;
else if (gb_res.marker == emark_late)
gb_res.marker = emark_toolong;
reset_frequency();
} else {
if (gb_res.marker == emark_none)
gb_res.marker = emark_minute;
else if (gb_res.marker == emark_toolong)
gb_res.marker = emark_late;
}
}
break; /* start of new second */
}
twait = (long long)(sec2 * bit.realfreq / 1000000);
#if !defined(MACOS)
(void)clock_gettime(CLOCK_MONOTONIC, &tp1);
twait = twait - (tp1.tv_sec - tp0.tv_sec) * 1000000000 -
(tp1.tv_nsec - tp0.tv_nsec);
#endif
slp.tv_sec = twait / 1000000000;
slp.tv_nsec = twait % 1000000000;
while (twait > 0 && nanosleep(&slp, &slp))
;
}
if (2 * bit.realfreq * bit.tlow * (1 + (newminute ? 1 : 0)) <
(bit.bit0 + bit.bit20) * bit.t) {
/* zero bit, ~100 ms active signal */
gb_res.bitval = ebv_0;
outch = '0';
buffer[bitpos] = 0;
} else if (bit.realfreq * bit.tlow * (1 + (newminute ? 1 : 0)) <
(bit.bit0 + bit.bit20) * bit.t) {
/* one bit, ~200 ms active signal */
gb_res.bitval = ebv_1;
outch = '1';
buffer[bitpos] = 1;
} else {
/* bad radio signal, retain old value */
gb_res.bitval = ebv_none;
outch = '_';
/* force bit 20 to be 1 to recover from too low b20 value */
if (bitpos == 20) {
gb_res.bitval = ebv_1;
outch = '1';
buffer[20] = 1;
}
}
if (init_bit == 1)
init_bit--;
else if (gb_res.hwstat == ehw_ok && gb_res.marker == emark_none) {
if (bitpos == 0 && gb_res.bitval == ebv_0)
bit.bit0 += ((long long)
(bit.tlow * 1000000 - bit.bit0) / 2);
if (bitpos == 20 && gb_res.bitval == ebv_1)
bit.bit20 += ((long long)
(bit.tlow * 1000000 - bit.bit20) / 2);
/* During a thunderstorm the value of bit20 might underflow */
if (bit.bit20 < bit.bit0)
reset_bitlen();
}
report:
acc_minlen += 1000000 * bit.t / (bit.realfreq / 1000);
if (logfile != NULL) {
fprintf(logfile, "%c", outch);
if (gb_res.marker == emark_minute ||
gb_res.marker == emark_late)
fprintf(logfile, "a%uc%6.4f\n", acc_minlen,
(double)((bit.t * 1e6) / bit.realfreq));
}
if (gb_res.marker == emark_minute || gb_res.marker == emark_late)
cutoff = bit.t * 1000000 / (bit.realfreq / 10000);
return gb_res;
}
int
main(int argc, char *argv[])
{
struct sigaction sigact;
struct hardware hw;
int ch, min, res;
bool raw = false, verbose = true;
while ((ch = getopt(argc, argv, "qr")) != -1) {
switch (ch) {
case 'q' :
verbose = false;
break;
case 'r' :
raw = true;
break;
default:
printf("usage: %s [-qr]\n", argv[0]);
return EX_USAGE;
}
}
res = read_config_file(ETCDIR"/config.txt");
if (res != 0) {
cleanup();
return res;
}
res = set_mode_live();
if (res != 0) {
cleanup();
return res;
}
hw = get_hardware_parameters();
sigact.sa_handler = do_cleanup;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = 0;
sigaction(SIGINT, &sigact, (struct sigaction *)NULL);
min = -1;
for (;;) {
struct bitinfo bi;
struct GB_result bit;
if (raw) {
struct timespec slp;
slp.tv_sec = 1.0 / hw.freq;
slp.tv_nsec = 1e9 / hw.freq;
printf("%i", get_pulse());
fflush(stdout);
while (nanosleep(&slp, &slp))
;
continue;
}
bit = get_bit_live();
bi = get_bitinfo();
if (verbose) {
if (bi.freq_reset)
printf("!");
/* display first bi->t pulses */
for (unsigned long long i = 0; i < bi.t / 8; i++)
for (unsigned j = 0; j < 8; j++)
printf("%c",
(bi.signal[i] & (1 << j)) > 0 ?
'+' : '-');
/*
* display pulses in the last partially filled item
* bi.t is 0-based, hence the <= comparison
*/
for (unsigned j = 0; j <= (bi.t & 7); j++)
printf("%c",
(bi.signal[bi.t / 8] & (1 << j)) > 0 ?
'+' : '-');
printf("\n");
}
if (bit.marker == emark_toolong || bit.marker == emark_late)
min++;
printf("%i %i %u %llu %llu %llu %i:%i\n",
bi.tlow, bi.tlast0, bi.t, bi.bit0, bi.bit20, bi.realfreq,
min, get_bitpos());
if (bit.marker == emark_minute)
min++;
bit = next_bit();
}
/* NOTREACHED */
}
