firmware: Analog read was to shaky, the number of read per millisecond is now increased to 20. meas.py: Some modifications to get the output more userfriendly. CSV output is implemented now.

firmware/command_ctrl.ino

@@ -222,8 +222,16 @@ void cc_startMeasurement()
       {
         // 3. on every loop read the analog input A0 and A1 for the in intervall (milliseconds)
         //    and generate the average value, read the ADC value every milli second.
-        a0_sum += analogRead(A0);
+        uint8_t t = 0;
-        a1_sum += analogRead(A1);
+        uint16_t ta0 = 0;
+        uint16_t ta1 = 0;
+        for (t = 0; t < 20; t++)
+        {
+          ta0 += analogRead(A0);
+          ta1 += analogRead(A1);
+        }
+        a0_sum += (ta0 / 20);
+        a1_sum += (ta1 / 20);
 
         delay(1);
       }

tools/meas.py

@@ -68,11 +68,6 @@ THREAD_LOOP_DELAY_S = 0.01
 
 ###############################################################################
 
-MUX_MIN_VAL = 0
-MUX_MAX_VAL = 7
-
-###############################################################################
-
 ser    = None
 device = "/dev/ttyUSB0"
 
@@ -339,6 +334,18 @@ def sendSerialData(data):
 
 ###############################################################################
 
+def user_friendly_freq(f):
+
+  if f >= 1000000:
+    return str(f / 1000000.0) + " MHz"
+
+  elif f >= 1000:
+    return str(f / 1000.0) + " kHz"
+
+  return str(f) + " Hz"
+
+###############################################################################
+
 if __name__ == "__main__":
 
   start_freq = 0
@@ -447,7 +454,7 @@ if __name__ == "__main__":
           a0   += e[3][5]
           a1    = e[3][6] << 8
           a1   += e[3][7]
-          print "freq: " + str(freq)
+          print "freq: " + user_friendly_freq(freq)
           print "a0: " + str(a0)
           print "a1: " + str(a1)
 
@@ -471,11 +478,11 @@ if __name__ == "__main__":
           intervall += e[3][13]
           drive_str = e[3][14]
 
-          print "start_freq = " + str(start_freq)
+          print "start_freq = " + user_friendly_freq(start_freq)
-          print "end_freq   = " + str(end_freq)
+          print "end_freq   = " + user_friendly_freq(end_freq)
-          print "step_freq  = " + str(step_freq)
+          print "step_freq  = " + user_friendly_freq(step_freq)
-          print "intervall  = " + str(intervall)
+          print "intervall  = " + str(intervall) + " ms"
-          print "drive_str  = " + str(drive_str)
+          print "drive_str  = " + str((drive_str + 1) * 2) + " mA"
 
           if args.start_meas == True and config_read == False:
             dataSend = dataSend + 1 + ((end_freq - start_freq) / step_freq)
@@ -489,20 +496,34 @@ if __name__ == "__main__":
           meas_r = []
           meas_p = []
 
+          min_vswr = [ 10, 0 ] # the default VSWR is 10 and the default freq is 0]
+
           i = ((drive_str + 1) * 2.0) / 1000.0
 
           if args.output_file != None or args.show_graph == True:
             for m in meas_data:
 
               meas_freq.append(m[0])
+              vswr = 0
 
-              if m[1] > m[2]:
+              if m[1] > 0 and m[2] > 0:
-                meas_ratio.append(m[1] / m[2])
+                if m[1] > m[2]:
-              elif m[1] < m[2]:
+                  vswr = (m[1] / m[2])
-                meas_ratio.append(m[2] / m[1])
+                  meas_ratio.append(vswr)
+                elif m[1] < m[2]:
+                  vswr = (m[2] / m[1])
+                  meas_ratio.append(vswr)
+                else:
+                  vswr = 1
+                  meas_ratio.append(1)
               else:
+                vswr = 1
                 meas_ratio.append(1)
 
+              if vswr < min_vswr[0]:
+                min_vswr[0] = vswr
+                min_vswr[1] = m[0] # the frequency
+
               # R = meas_data[0] * 5V / 1023 * I
               r = (m[1] * 5.0 / 1023.0) / i
               meas_r.append(r)
@@ -514,7 +535,13 @@ if __name__ == "__main__":
                 meas_p.append(0)
 
           if args.output_file != None:
-            pass # TODO impl
+            FILE = open(args.output_file, "w")
+            j = 0
+            for m in meas_ratio:
+              FILE.write("%f;%f;%f;%f;%f\n" % (meas_freq[j], m, meas_r[j], meas_p[j], i))
+              j = j + 1
+            FILE.close()
+            print "Output file " + args.output_file + " written."
 
           if args.show_graph == True:
             plt.plot(meas_freq, meas_ratio)
@@ -524,6 +551,8 @@ if __name__ == "__main__":
             print "Please close the mathplot window to exit..."
             plt.show()
 
+          print "First minimum VSWR " + str(min_vswr[0]) + " found at freqency " + user_friendly_freq(min_vswr[1])
+
         else:
           print "err: unknown type 0x%02x" % (e[1])
           break