update exception

main.py

@@ -44,9 +44,10 @@ else:
 	try:
 		# If the rpi_ws281x Python module is available, then use that...
 		from raspberrypihal import RaspberryPiHAL as HAL
-	except:
+	except :
 		# ...else assume that there's an MCU (driving the display) connected
 		# to a serial port
+		e = sys.exc_info()[0]
 		print('HAL: failed: {}'.format(e.args[0]))
 		from arduinoserialhal import ArduinoSerialHAL as HAL