Add ppm_error option

include/dsd.h

@@ -89,6 +89,7 @@ typedef struct
   PaStream* audio_in_pa_stream;
 #endif
   uint32_t rtlsdr_center_freq;
+  int rtlsdr_ppm_error;
   int audio_in_type; // 0 for device, 1 for file, 2 for portaudio, 3 for rtlsdr
   char audio_out_dev[1024];
   int audio_out_fd;

src/dsd_main.c

@@ -275,6 +275,7 @@ usage ()
   printf ("  -w <file>     Output synthesized speech to a .wav file\n");
   printf ("  -a            Display port audio devices\n");
   printf ("  -c <hertz>    RTL-SDR center frequency\n");
+  printf ("  -P <num>      RTL-SDR ppm error (default = 0)\n");
   printf ("\n");
   printf ("Scanner control options:\n");
   printf ("  -B <num>      Serial port baud rate (default=115200)\n");
@@ -513,7 +514,7 @@ main (int argc, char **argv)
   exitflag = 0;
   signal (SIGINT, sigfun);
 
-  while ((c = getopt (argc, argv, "haep:qstv:z:i:o:d:c:g:nw:B:C:R:f:m:u:x:A:S:M:rl")) != -1)
+  while ((c = getopt (argc, argv, "haep:P:qstv:z:i:o:d:c:g:nw:B:C:R:f:m:u:x:A:S:M:rl")) != -1)
     {
       opterr = 0;
       switch (c)
@@ -550,6 +551,9 @@ main (int argc, char **argv)
              opts.unmute_encrypted_p25 = 1;
             }
           break;
+        case 'P':
+          sscanf (optarg, "%i", &opts.rtlsdr_ppm_error);
+          break;
         case 'q':
           opts.errorbars = 0;
           opts.verbose = 0;

src/rtl_sdr_fm.cpp

@@ -901,6 +901,10 @@ void open_rtlsdr_stream(dsd_opts *opts)
 		controller.freq_len++;
 	}
 
+	if (opts->rtlsdr_ppm_error > 0) {
+		dongle.ppm_error = opts->rtlsdr_ppm_error;
+	}
+
   /* quadruple sample_rate to limit to Δθ to ±π/2 */
 	demod.rate_in *= demod.post_downsample;