configurable decimation rate

rtl_wmbus.c

@@ -446,19 +446,21 @@ static void time2_algorithm(unsigned bit, unsigned rssi, struct time2_algorithm
 
 static int opts_run_length_algorithm_enabled = 1;
 static int opts_time2_algorithm_enabled = 1;
+static unsigned decimation_rate = 2u;
 
 static void print_usage(const char *program_name)
 {
     fprintf(stdout, "Usage %s:\n", program_name);
     fprintf(stdout, "\t-r 0 to disable run length algorithm\n");
     fprintf(stdout, "\t-t 0 to disable time2 algorithm\n");
+    fprintf(stdout, "\t-d 2 set decimation rate to 2 (defaults to 2 if omitted)\n");
 }
 
 static void process_options(int argc, char *argv[])
 {
     int option;
 
-    while ((option = getopt(argc, argv, "r:t:")) != -1)
+    while ((option = getopt(argc, argv, "d:r:t:")) != -1)
     {
         switch (option)
         {
@@ -484,6 +486,9 @@ static void process_options(int argc, char *argv[])
                 exit(EXIT_FAILURE);
             }
             break;
+        case 'd':
+            decimation_rate = strtoul(optarg, NULL, 10);
+            break;
         default:
             print_usage(argv[0]);
             exit(EXIT_FAILURE);
@@ -500,7 +505,7 @@ int main(int argc, char *argv[])
     // configurable via command line.
     const unsigned CLOCK_LOCK_THRESHOLD = 2;
 
-    const unsigned DECIMATION_RATE = 2;
+
     // --- parameter section end ---
 
     __attribute__((__aligned__(16))) uint8_t samples[4096];
@@ -577,7 +582,7 @@ int main(int argc, char *argv[])
 #endif
 
             ++decimation_rate_index;
-            if (decimation_rate_index < DECIMATION_RATE) continue;
+            if (decimation_rate_index < decimation_rate) continue;
             decimation_rate_index = 0;
 
             // Demodulate.
@@ -602,7 +607,7 @@ int main(int argc, char *argv[])
             rssi = rssi_filter(rssi); // comment out, if rssi filtering is unwanted
 #if defined(USE_MOVING_AVERAGE)
             // If using moving average, we would have doubles of each of i- and q- signal components.
-            rssi /= DECIMATION_RATE;
+            rssi /= decimation_rate;
 #endif
             // --- rssi filtering section end ---