Fixed an issue mentioned in issue #19 where a UnicodeError would be raised when there was noise over UART

README.rst

@@ -41,7 +41,7 @@ Feather boards and many other circuitpython boards will round to two decimal pla
     >>> float('1234.5678')
     1234.57
 
-This isn't ideal for gps data as this lowers the accuracty from 0.1m to 11m. 
+This isn't ideal for gps data as this lowers the accuracy from 0.1m to 11m. 
 
 This can be fixed by using string formatting when the gps data is outputted.
 

adafruit_gps.py

@@ -99,7 +99,10 @@ def update(self):
         """
         # Grab a sentence and check its data type to call the appropriate
         # parsing function.
-        sentence = self._parse_sentence()
+        try:
+            sentence = self._parse_sentence()
+        except UnicodeError:
+            return None
         if sentence is None:
             return False
         if self.debug:
@@ -145,7 +148,10 @@ def _parse_sentence(self):
         sentence = self._uart.readline()
         if sentence is None or sentence == b'' or len(sentence) < 1:
             return None
-        sentence = str(sentence, 'ascii').strip()
+        try:
+            sentence = str(sentence, 'ascii').strip()
+        except UnicodeError:
+            return None
         # Look for a checksum and validate it if present.
         if len(sentence) > 7 and sentence[-3] == '*':
             # Get included checksum, then calculate it and compare.