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command line options for Rs and M, limiting Sf to 256 points over dahsboard link to prevent buffer overflows

master
David Rowe 2020-08-09 11:36:32 +09:30
parent 656317a3a5
commit a01cb568f6
1 changed files with 50 additions and 27 deletions
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77
src/rtl_fsk.c
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@ -48,6 +48,9 @@
#define MAXIMAL_BUF_LENGTH (256 * 16384)
#define BUF_SZ 8192
#define NORM_RX_TIMING_LOG_SZ 1024
#define DEFAULT_SYMBOL_RATE 10000 /* symbols/s */
#define DEFAULT_M 2 /* 2FSK */
#define NDFT 256 /* number of DFT points on dashboard */
static int do_exit = 0;
static uint32_t bytes_to_read = 0;
@ -56,6 +59,7 @@ static struct FSK *fsk;
static uint32_t out_block_size = DEFAULT_BUF_LENGTH;
static unsigned char *rawbuf;
static size_t nrawbuf = 0;
static size_t nrawbuf_max = 0;
static int dashboard = 0;
static int sockfd;
static struct sockaddr_in serveraddr;
@ -77,8 +81,10 @@ void usage(void)
"\t[-b output_block_size (default: 16 * 16384)]\n"
"\t[-n number of samples to read (default: 0, infinite)]\n"
"\t[-S force sync output (default: async)]\n"
"\t[-r FSK modem symbol rate (default: %d Hz)]\n"
"\t[-m number of FSK modem tones (default: %d)]\n"
"\t[-u hostname (optional hostname:8001 where we send UDP dashboard diagnostics)\n"
"\tfilename (a '-' dumps bits to stdout)\n\n", DEFAULT_SAMPLE_RATE);
"\tfilename (a '-' dumps bits to stdout)\n\n", DEFAULT_SAMPLE_RATE, DEFAULT_SYMBOL_RATE, DEFAULT_M);
exit(1);
}
@ -141,7 +147,8 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
memcpy(&rawbuf[nrawbuf],buf,len);
nrawbuf += len;
assert(nrawbuf < 2*out_block_size);
assert(nrawbuf < nrawbuf_max);
/* process as many samples in rawbuf as possible */
pout = rawbuf;
while(nrawbuf >= 2*fsk_nin(fsk)) {
@ -158,41 +165,49 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
fprintf(stderr, "Short write, bits lost, exiting!\n");
rtlsdr_cancel_async(dev);
}
if (dashboard) {
/* update buffer of timing samples */
if (norm_rx_timing_log_index < NORM_RX_TIMING_LOG_SZ)
norm_rx_timing_log[norm_rx_timing_log_index++] = fsk->norm_rx_timing;
else
fprintf(stderr, "norm_rx_timing_log full!");
}
if (dashboard) {
sample_counter += fsk_nin(fsk);
if (sample_counter > samp_rate) {
/* one second has passed, lets send some debug information */
/* one second has passed, lets send some dashboard information */
char buf[BUF_SZ];
char buf1[BUF_SZ];
size_t Ndft;
float *f_est;
int m;
float *f_est, sum;
int m, step, start, k;
float SfdB[NDFT];
sample_counter -= samp_rate;
buf[0]=0;
/* Current magnitude spectrum Sf[] from freq estimator */
snprintf(buf1, BUF_SZ, "{"); strncat(buf, buf1, BUF_SZ);
snprintf(buf1, BUF_SZ, "\"Sf\":["); strncat(buf, buf1, BUF_SZ);
Ndft = fsk->Ndft;
for(i=0; i<Ndft; i++) {
snprintf(buf1, BUF_SZ, "%f",(fsk->Sf)[i]); strncat(buf, buf1, BUF_SZ);
if(i<Ndft-1) { snprintf(buf1, BUF_SZ, ", "); strncat(buf, buf1, BUF_SZ); }
/* Limit spectrum to NDFT points */
step = fsk->Ndft/NDFT;
for(i=0, start=0; i<NDFT; i++, start+=step) {
/* Sf[] array is linear magnitudes */
sum = 0.0;
for(k=0; k<step; k++)
sum += fsk->Sf[start+k];
SfdB[i] = 20.0*log10(sum);
}
snprintf(buf1, BUF_SZ, "]"); strncat(buf, buf1, BUF_SZ);
snprintf(buf1, BUF_SZ, "{"); strncat(buf, buf1, BUF_SZ);
snprintf(buf1, BUF_SZ, "\"SfdB\":["); strncat(buf, buf1, BUF_SZ);
for(i=0; i<NDFT; i++) {
snprintf(buf1, BUF_SZ, "%f",SfdB[i]); strncat(buf, buf1, BUF_SZ);
if(i<NDFT-1) { snprintf(buf1, BUF_SZ, ", "); strncat(buf, buf1, BUF_SZ); }
}
snprintf(buf1, BUF_SZ, "]"); strncat(buf, buf1, BUF_SZ);
/* FSK tone freq estimates */
if (fsk->freq_est_type)
if (fsk->freq_est_type)
f_est = fsk->f2_est;
else
f_est = fsk->f_est;
@ -214,7 +229,7 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
snprintf(buf1, BUF_SZ, ", \"SNRest_lin\":%f, \"Fs_Hz\":%d",
fsk->SNRest, fsk->Fs); strncat(buf, buf1, BUF_SZ);
/* finish up JSON and send to GUI */
/* finish up JSON and send to dashboard GUI over UDP */
snprintf(buf1, BUF_SZ, "}\n"); strncat(buf, buf1, BUF_SZ);
udp_sendbuf(buf);
fprintf(stderr, "Tick\n");
@ -247,8 +262,10 @@ int main(int argc, char **argv)
int dev_given = 0;
char hostname[256];
uint32_t frequency = 100000000;
while ((opt = getopt(argc, argv, "d:f:g:s:b:n:p:S:u:")) != -1) {
int Rs = DEFAULT_SYMBOL_RATE;
int M = DEFAULT_M;
while ((opt = getopt(argc, argv, "d:f:g:s:b:n:p:S:u:r:m:")) != -1) {
switch (opt) {
case 'd':
dev_index = verbose_device_search(optarg);
@ -272,6 +289,12 @@ int main(int argc, char **argv)
case 'n':
bytes_to_read = (uint32_t)atof(optarg) * 2;
break;
case 'r':
Rs = atoi(optarg);
break;
case 'm':
M = atoi(optarg);
break;
case 'S':
sync_mode = 1;
break;
@ -303,7 +326,8 @@ int main(int argc, char **argv)
}
buffer = malloc(out_block_size * sizeof(uint8_t));
rawbuf = malloc(2 * out_block_size * sizeof(uint8_t));
nrawbuf_max = 2 * out_block_size;
rawbuf = malloc(nrawbuf_max * sizeof(uint8_t));
nrawbuf = 0;
/* create UDP socket for debug/status information */
@ -390,17 +414,16 @@ int main(int argc, char **argv)
{
/* TODO: make some of these command line options */
int Fs = DEFAULT_SAMPLE_RATE;
int Rs = 10000;
int M = 2;
int Fs = samp_rate;
int P = Fs/Rs;
fsk = fsk_create_hbr(Fs,Rs,M,P,FSK_DEFAULT_NSYM,FSK_NONE,100);
fprintf(stderr,"FSK Demod Rs: %3.1f kHz M: %d P: %d Ndft: %d\n", (float)Rs/1000, M, P, fsk->Ndft);
}
{
/* TODO: fsk_lower might need some adjustment, so we avoid the RTLSDR DC line. We really need a GUI
plot of the spectrum and tone estimates to observe what's going on */
int fsk_lower = 0;
int fsk_upper = DEFAULT_SAMPLE_RATE/2;
int fsk_upper = samp_rate/2;
fprintf(stderr,"Setting estimator limits to %d to %d Hz.\n", fsk_lower, fsk_upper);
fsk_set_freq_est_limits(fsk,fsk_lower,fsk_upper);
}