going to python3 + c converter for binary formats

README.txt

@@ -2,7 +2,7 @@ Light Funcube Reader
 
 For educational purpose
 
-Beware, wont compile, needs HIDAPI to work
+Beware, wont compile, needs HIDAPI and fcdctl to work
 see //github.com/csete/fcdctl.git
 
 example:
@@ -15,6 +15,9 @@ example:
   or process AM demodulation with
   ./try-pyam fcrec.dat
 
+dependencies
+  Install sox
+
 TODO
-  correct build against HIDAPI
+  correct build against HIDAPI and fcdctl
 

demodam.py

@@ -12,8 +12,8 @@
 c=0
 liq = []
 llen = len(ll)
-llen2 = llen/2
-for c in xrange(llen2):
+llen2 = int(llen/2)
+for c in range(llen2):
   i = ll[2*c]
   q = ll[2*c+1]
   liq.append((i, q))
@@ -27,7 +27,7 @@
 coeff = 10.
 mx=0
 mn=0
-for c in xrange(llen2):
+for c in range(llen2):
   i = float(ll[2*c])
   q = float(ll[2*c+1])
   v = coeff * math.sqrt(i*i + q*q)
@@ -37,14 +37,16 @@
 
 print("mx "+str(mx))
 print("mn "+str(mn))
+mid=0.5*(mx+mn)
 
 # ascii dump
 fd = open("demodam.dat", 'w')
-for v in lv: fd.write(str(v)+"\n")
+for v in lv: fd.write(str(int(v-mid))+"\n")
 fd.close()
 
 # scipy wav dump
 #import scipy.io.wavfile
 #import numpy
+#lv = map(lambda x: x/(mx-mid), lv)
 #scipy.io.wavfile.write("sample.wav", freq, numpy.array(lv))
 

demodfm.py

@@ -12,8 +12,8 @@
 c=0
 liq = []
 llen = len(ll)
-llen2 = llen/2
-for c in xrange(llen2):
+llen2 = int(llen/2)
+for c in range(llen2):
   i = ll[2*c]
   q = ll[2*c+1]
   liq.append((i, q))
@@ -37,7 +37,7 @@ def regul(dtheta):
 theta0=0.
 mx=0
 mn=0
-for c in xrange(llen2):
+for c in range(llen2):
   i = ll[2*c]
   q = ll[2*c+1]
   theta1 = math.atan2(float(q), float(i))
@@ -54,11 +54,12 @@ def regul(dtheta):
 
 # ascii dump
 fd = open("demodfm.dat", 'w')
-for v in lv: fd.write(str(v)+"\n")
+for v in lv: fd.write(str(int(v))+"\n")
 fd.close()
 
 # scipy wav dump
 #import scipy.io.wavfile
 #import numpy
+#lv = map(lambda x: 0.5*x/mx, lv)
 #scipy.io.wavfile.write("sample.wav", freq, numpy.array(lv))
 

fcrec.c

@@ -9,8 +9,6 @@
 
 #include <math.h>
 
-// based on the #defines for TLGE_P10_0DB etc. from fcdhidcmd.h :
-double lnagainvalues[]={-5.0,-2.5,-999,-999,0,2.5,5,7.5,10,12.5,15,17.5,20,25,30};
 
 inline double sqr(double x) { return x*x; }
 
@@ -21,16 +19,23 @@ void writeAscii(FILE *fdo, short int *buf, int n)
 }
 
 /********************************************************************/
-/** statistics **/
+/** statistics && power **/
 
 struct statT {
   int nb;
   double sx;
   double sx2;
 };
 
+void stats_reset(struct statT *st)
+{
+  st->nb = 0;
+  st->sx = st->sx2 = 0.;
+}
+
 void stats_sum(struct statT *st, short int *buf, int n)
 {
+  /// add content of buffer to stats in st
   int c=0;
   for (c=0; c<n; c++) {
     st->sx += buf[c];
@@ -59,14 +64,26 @@ void stats_edit(FILE *fdo, struct statT *st)
   fprintf(fdo, "sdev %g\n", sqrt(var));
 }
 
+void stats_add(struct statT *st1, struct statT *st2)
+{
+  /// add stat of st2 to st1
+  st1->nb += st2->nb;
+  st1->sx += st2->sx;
+  st1->sx2 += st2->sx2;
+}
+
 int stats_high(struct statT *st, double sql)
 {
+  /// tells if var (or power) is above level
   return stats_var(st, stats_mean(st)) > sql;
 }
 
 /****************************************************************/
 /** SDR stuff **/
 
+// based on the #defines for TLGE_P10_0DB etc. from fcdhidcmd.h :
+double lnagainvalues[]={-5.0,-2.5,-999,-999,0,2.5,5,7.5,10,12.5,15,17.5,20,25,30};
+
 snd_pcm_t *handle;
 snd_pcm_uframes_t frames;
 snd_pcm_hw_params_t *params;
@@ -78,10 +95,10 @@ void dumpSdr()
   fcdGetFwVerStr(version);
   printf("# funcube version %s\n", version);
 
-  uint8_t f[8];
-  fcdAppGetParam(FCD_CMD_APP_GET_FREQ_HZ, f, 8);
-  printf("# frequency %g MHz\n", (*(int*)f)/1e6);
-  
+  // uint8_t f[8];
+  // fcdAppGetParam(FCD_CMD_APP_GET_FREQ_HZ, f, 8);
+  // printf("# frequency %g MHz\n", (*(int*)f)/1e6);
+
   uint8_t lnagain;
   fcdAppGetParam(FCD_CMD_APP_GET_LNA_GAIN, &lnagain, 1);
   printf("# lna gain %g\n", lnagainvalues[lnagain]);
@@ -195,7 +212,7 @@ void readFuncube(char *buffer, double time, int sz, double sql)
    sz is size of frames
    */
   int dir, rc;
-  long loops;
+  long loops, rloops=0;
   unsigned int val;
 
   printf("dumping file fcrec.raw\n");
@@ -208,7 +225,8 @@ void readFuncube(char *buffer, double time, int sz, double sql)
   /* time seconds in microseconds divided by period time */
   loops = time * 1000000 / val;
   printf("loops %ld\n", loops);
-  struct statT st = { 0, 0., 0. };
+  struct statT sta = { 0, 0., 0. }, // stats for all loops
+	       st;		    // stat for just one loop
 
   while (loops > 0) {
     rc = snd_pcm_readi(handle, buffer, frames);
@@ -222,15 +240,21 @@ void readFuncube(char *buffer, double time, int sz, double sql)
     else if (rc != (int)frames)
       fprintf(stderr, "short read, read %d frames\n", rc);
     // read has been fully satistory
-    else if (stats_high(&st, sql)) {
-      if (write(fdob, buffer, sz*rc) != sz*rc) abort();
-      writeAscii(fdoa, (short int *)buffer, sz*rc/2);
+    else {
+      stats_reset(&st);
+      stats_sum(&st, (short int *)buffer, sz*rc/2);
+      if (stats_high(&st, sql)) {
+	if (write(fdob, buffer, sz*rc) != sz*rc) abort();
+	writeAscii(fdoa, (short int *)buffer, sz*rc/2);
+	rloops++;
+      }
+      stats_add(&sta, &st);
     }
-    stats_sum(&st, (short int *)buffer, sz*rc/2);
     loops--;
   }
 
-  stats_edit(fdoa, &st);
+  printf("loops really done (squelch) %ld\n", rloops);
+  stats_edit(stdout, &sta);
   close(fdob);
   fclose(fdoa);
 }
@@ -249,6 +273,7 @@ int main(int argc, char **argv) {
   double time = atof(argv[3]);
   double sql=0;
   if (argc>4) sql = atof(argv[4]);
+  printf("squelch %g\n", sql);
   openFuncubeSdr(freq, gain);
   //dumpSdr();
   char *buffer =openFuncubePcm(freq);

makefile

@@ -1,10 +1,13 @@
-all	: fcrec
+all	: fcrec convertasc
 
 convertbin	: convertbin.c
 	gcc -O3 -Wall -Wextra convertbin.c -lm -o convertbin
 
-fcrec	: fcrec.o fcd.o hid-libusb.o
-	gcc -O3 -Wall -Wextra fcrec.o fcd.o hid-libusb.o `pkg-config --libs libusb-1.0` -lm -lpthread -lasound -o fcrec
+convertasc	: convertasc.c
+	gcc -O3 -Wall -Wextra convertasc.c -lm -o convertasc
+
+fcrec	: fcrec.o fcd.o
+	gcc -O3 -Wall -Wextra fcrec.o fcd.o `pkg-config --libs hidapi-hidraw` `pkg-config --libs libusb-1.0` -lm -lpthread -lasound -o fcrec
 
 %.o	: %.c
 	gcc -c -O3 -Wall -Wextra $< `pkg-config --cflags libusb-1.0` -o $@

try-pyam

@@ -1,11 +1,10 @@
 #!/bin/sh
 
-rm -f sample.wav
-python demodam.py $1
+rm -f sample.{raw,wav}
+python3 demodam.py $1
 
 # convert txt to wav
-convertasc.opt demodam.dat S16LE
-cp -v sample.bin sample.raw
+./convertasc demodam.dat S16LE
 sox -r 96000 -L -t s16 -c 1 sample.raw sample.wav gain 0
 
 # play wav file

try-pyfm

@@ -1,11 +1,10 @@
 #!/bin/sh
 
-rm -f sample.wav
-python demodfm.py $1
+rm -f sample.{raw,wav}
+python3 demodfm.py $1
 
 # convert txt to wav
-convertasc.opt demodfm.dat S16LE
-cp -v sample.bin sample.raw
+make convertasc && ./convertasc demodfm.dat S16LE
 sox -r 96000 -L -t s16 -c 1 sample.raw sample.wav gain 0
 
 # play wav file