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rtl_test: useful ppm

Browse Source 
Signed-off-by: Steve Markgraf <steve@steve-m.de>
This commit is contained in:
Kyle Keen
2014-01-23 01:25:43 -05:00
committed by Steve Markgraf
parent 8520c7c3d7
commit 835bd23542
1 changed files with 63 additions and 27 deletions
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90
src/rtl_test.c
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@@ -53,8 +53,13 @@ static int do_exit = 0;
static rtlsdr_dev_t *dev = NULL;
static int ppm_benchmark = 0;
static int ppm_running = 0;
static int64_t ppm_count = 0L;
static int64_t ppm_total = 0L;
uint32_t samp_rate = DEFAULT_SAMPLE_RATE;
long total_samples;
long dropped_samples;
#ifndef _WIN32
static struct timespec ppm_start;
@@ -103,17 +108,15 @@ static void sighandler(int signum)
}
#endif
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
static void underrun_test(unsigned char *buf, uint32_t len, int mute)
{
uint32_t i, lost = 0;
int64_t ns;
static uint8_t bcnt, uninit = 1;
if (uninit) {
bcnt = buf[0];
uninit = 0;
}
for (i = 0; i < len; i++) {
if(bcnt != buf[i]) {
lost += (buf[i] > bcnt) ? (buf[i] - bcnt) : (bcnt - buf[i]);
@@ -123,12 +126,43 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
bcnt++;
}
total_samples += (long)len;
dropped_samples += (long)lost;
if (mute)
return;
if (lost)
printf("lost at least %d bytes\n", lost);
if (!ppm_benchmark) {
return;
}
}
static void ppm_clock_init(void)
{
#ifdef __APPLE__
gettimeofday(&tv, NULL);
ppm_recent.tv_sec = tv.tv_sec;
ppm_recent.tv_nsec = tv.tv_usec*1000;
ppm_start.tv_sec = tv.tv_sec;
ppm_start.tv_nsec = tv.tv_usec*1000;
#elif __unix__
clock_gettime(CLOCK_REALTIME, &ppm_recent);
clock_gettime(CLOCK_REALTIME, &ppm_start);
#endif
}
static int ppm_report(void)
{
int real_rate;
int64_t ns;
ns = 1000000000L * (int64_t)(ppm_recent.tv_sec - ppm_start.tv_sec);
ns += (int64_t)(ppm_recent.tv_nsec - ppm_start.tv_nsec);
real_rate = (int)(ppm_total * 1000000000L / ns);
return (int)round((double)(1000000 * (real_rate - (int)samp_rate)) / (double)samp_rate);
}
static void ppm_test(uint32_t len)
{
int64_t ns;
ppm_count += (int64_t)len;
#ifndef _WIN32
#ifndef __APPLE__
@@ -141,7 +175,7 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
if (ppm_now.tv_sec - ppm_recent.tv_sec > PPM_DURATION) {
ns = 1000000000L * (int64_t)(ppm_now.tv_sec - ppm_recent.tv_sec);
ns += (int64_t)(ppm_now.tv_nsec - ppm_recent.tv_nsec);
printf("real sample rate: %i\n",
printf("real sample rate: %i",
(int)((1000000000L * ppm_count / 2L) / ns));
#ifndef __APPLE__
clock_gettime(CLOCK_REALTIME, &ppm_recent);
@@ -152,10 +186,26 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
#endif
ppm_total += ppm_count / 2L;
ppm_count = 0L;
printf(" cumulative ppm: %i\n", ppm_report());
}
#endif
}
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
{
underrun_test(buf, len, 0);
if (ppm_benchmark && !ppm_running) {
ppm_clock_init();
ppm_running = 1;
return;
}
if (ppm_benchmark) {
ppm_test(len);
}
}
void e4k_benchmark(void)
{
uint32_t freq, gap_start = 0, gap_end = 0;
@@ -214,12 +264,9 @@ int main(int argc, char **argv)
uint8_t *buffer;
int dev_index = 0;
int dev_given = 0;
uint32_t samp_rate = DEFAULT_SAMPLE_RATE;
uint32_t out_block_size = DEFAULT_BUF_LENGTH;
int count;
int gains[100];
int real_rate;
int64_t ns;
while ((opt = getopt(argc, argv, "d:s:b:tpS::")) != -1) {
switch (opt) {
@@ -314,16 +361,6 @@ int main(int argc, char **argv)
if (ppm_benchmark && !sync_mode) {
fprintf(stderr, "Reporting PPM error measurement every %i seconds...\n", ppm_benchmark);
fprintf(stderr, "Press ^C after a few minutes.\n");
#ifdef __APPLE__
gettimeofday(&tv, NULL);
ppm_recent.tv_sec = tv.tv_sec;
ppm_recent.tv_nsec = tv.tv_usec*1000;
ppm_start.tv_sec = tv.tv_sec;
ppm_start.tv_nsec = tv.tv_usec*1000;
#elif __unix__
clock_gettime(CLOCK_REALTIME, &ppm_recent);
clock_gettime(CLOCK_REALTIME, &ppm_start);
#endif
}
if (!ppm_benchmark) {
@@ -335,6 +372,7 @@ int main(int argc, char **argv)
if (sync_mode) {
fprintf(stderr, "Reading samples in sync mode...\n");
fprintf(stderr, "(Samples are being lost but not reported.)\n");
while (!do_exit) {
r = rtlsdr_read_sync(dev, buffer, out_block_size, &n_read);
if (r < 0) {
@@ -346,6 +384,7 @@ int main(int argc, char **argv)
fprintf(stderr, "Short read, samples lost, exiting!\n");
break;
}
underrun_test(buffer, n_read, 1);
}
} else {
fprintf(stderr, "Reading samples in async mode...\n");
@@ -355,15 +394,12 @@ int main(int argc, char **argv)
if (do_exit) {
fprintf(stderr, "\nUser cancel, exiting...\n");
if (ppm_benchmark) {
fprintf(stderr, "Samples per million lost (minimum): %i\n", (int)(1000000L * dropped_samples / total_samples));
#ifndef _WIN32
ns = 1000000000L * (int64_t)(ppm_recent.tv_sec - ppm_start.tv_sec);
ns += (int64_t)(ppm_recent.tv_nsec - ppm_start.tv_nsec);
real_rate = (int)(ppm_total * 1000000000L / ns);
printf("Cumulative PPM error: %i\n",
(int)round((double)(1000000 * (real_rate - (int)samp_rate)) / (double)samp_rate));
#endif
if (ppm_benchmark) {
printf("Cumulative PPM error: %i\n", ppm_report());
}
#endif
}
else
fprintf(stderr, "\nLibrary error %d, exiting...\n", r);