diff --git a/bin/weewx/drivers/ultimeter.py b/bin/weewx/drivers/ultimeter.py
index 33979d46..8cae85ac 100644
--- a/bin/weewx/drivers/ultimeter.py
+++ b/bin/weewx/drivers/ultimeter.py
@@ -150,8 +150,8 @@ class Station(object):
     DEFAULT_PORT = '/dev/ttyUSB0'
 
     def __init__(self, port, debug_serial=0):
-        self._debug_serial = debug_serial
         self.port = port
+        self._debug_serial = debug_serial
         self.baudrate = 2400
         self.timeout = 3  # seconds
         self.serial_port = None
@@ -225,53 +225,59 @@ class Station(object):
                 log.debug("Set station to modem mode")
             self.serial_port.write(b">\r")
 
-    def get_readings_with_retry(self, max_tries=5, retry_wait=3):
+    def get_readings_with_retry(self, max_tries, retry_wait):
         for ntries in range(max_tries):
             try:
-                buf = self.get_readings()
+                buf = get_readings(self.serial_port, self._debug_serial)
                 validate_string(buf)
                 return buf
             except (serial.SerialException, weewx.WeeWxIOError) as e:
-                log.info("Failed attempt %d of %d to get readings: %s", ntries + 1, max_tries, e)
+                log.info("Failed attempt %d of %d to get readings: %s",
+                         ntries + 1, max_tries, e)
                 time.sleep(retry_wait)
         else:
             msg = "Max retries (%d) exceeded for readings" % max_tries
             log.error(msg)
             raise weewx.RetriesExceeded(msg)
 
-    def get_readings(self):
-        """Read an Ultimeter sentence.
-
-        Returns:
-            bytearray: A bytearray containing the sentence.
-        """
-
-        # Search for the character '!', which marks the beginning of a "sentence":
-        while True:
-            c = self.serial_port.read(1)
-            if c == b'!':
-                break
-        # Save the first '!' ...
-        buf = bytearray(c)
-        # ... then read until we get to a '\r' or '\n'
-        while True:
-            c = self.serial_port.read(1)
-            if c == b'\n' or c == b'\r':
-                # We found a carriage return or newline, so we have the complete sentence.
-                # NB: Because the Ultimeter terminates a sentence with a '\r\n', this will
-                # leave a newline in the buffer. We don't care: it will get skipped over when
-                # we search for the next sentence.
-                break
-            buf += c
-        if self._debug_serial:
-            log.debug("Station said: %s", _fmt(buf))
-        return buf
-
 
 # ##############################################################33
-#                 Decode utilities
+#                 Utilities
 # ##############################################################33
 
+def get_readings(serial_port, debug_serial):
+    """Read an Ultimeter sentence from a serial port.
+
+    Args:
+        serial_port (serial.Serial): An open port
+        debug_serial (int): Set to greater than zero for extra debug information.
+
+    Returns:
+        bytearray: A bytearray containing the sentence.
+    """
+
+    # Search for the character '!', which marks the beginning of a "sentence":
+    while True:
+        c = serial_port.read(1)
+        if c == b'!':
+            break
+    # Save the first '!' ...
+    buf = bytearray(c)
+    # ... then read until we get to a '\r' or '\n'
+    while True:
+        c = serial_port.read(1)
+        if c == b'\n' or c == b'\r':
+            # We found a carriage return or newline, so we have the complete sentence.
+            # NB: Because the Ultimeter terminates a sentence with a '\r\n', this will
+            # leave a newline in the buffer. We don't care: it will get skipped over when
+            # we search for the next sentence.
+            break
+        buf += c
+    if debug_serial:
+        log.debug("Station said: %s", _fmt(buf))
+    return buf
+
+
 def validate_string(buf, choices=None):
     """Validate a data buffer.