+ runningSum = 0
+
+ sample = music.readframes(numFramesToRead) # grab .1s of audio
+
+ length = len(sample)
+
+ for i in range(0, length,4):
+ runningSum += ord(sample[i]) #average the dual-channel
+ runningSum += ord(sample[i+2])
+
+ avg = runningSum/(length / 2) # we used 2 of every 4 frames, so divide length by 2
+
+ val = (40 + 5*(avg-120)) # normalize to speedometer range of values
+
+ print "speedometerVal = %f " %val;
+ print "speed = %f" %(1.617*val-63.5) # speed we're trying to display
+
+ if (val > 255): # ensure we don't run off acceptable range
+ val = 255
+ elif (val < 0):
+ val = 0
+
+ newPacket[9] = int(val) # write it to the packet
+
+ # load new packet into TXB0 and check time
+ self.multiPacketSpit(packet0=newPacket, packet0rts=True)
+ starttime = time.time()
+
+ # spit new value for 1 second
+ while (time.time()-starttime < .1):
+ self.multiPacketSpit(packet0rts=True)
+
+# read in 26 frames
+# average them
+# normalize to our range of values (conversion 1.6167*x-63.5
+# x --> 0 to 120
+
+#sample width = 2??
+#number of frames: 7133184
+#number of channels: 2
+#sample width: 2 --> 2 bytes per sample
+#framerate: 44100
+
+ def engineDiagnostic(self, data):
+
+ self.addFilter([513, 513, 513,513])
+
+ startTime = tT.time()
+ while((tT.time() - startTime ) < 15):
+ packet = None;
+
+ #catch a packet to decode
+ while (packet == None):
+ packet=self.client.rxpacket();
+
+ rpm = 64.5 * ord(packet[5]) - 61.88
+ mph = 1.617 * ord(packet[9]) - 63.5
+
+ data.put("Engine RPM: %d Current Speed: %d mph"%(rpm, mph))
+ time.sleep(.5)
+
+
+
+