Added analog inputs and buzzer with example

breakfast_serial/components.py

@@ -1,6 +1,6 @@
 from breakfast_serial import Arduino
 from util import EventEmitter, setInterval
-import pyfirmata
+import pyfirmata, re
 
 class ArduinoNotSuppliedException(Exception):
   pass
@@ -14,7 +14,25 @@ def __init__(self, board, pin):
     super(Component, self).__init__()
 
     self._board = board
-    self._pin = self._board.digital[pin]
+
+    analog_regex = re.compile('A(\d)')
+    match = analog_regex.match(str(pin))
+
+    if match:
+      self._pin = self._board.analog[int(match.group(1))]
+    else:
+      self._pin = self._board.digital[int(pin)]
+
+  @property
+  def value(self): return self._pin.value
+
+class Sensor(Component):
+
+  def __init__(self, board, pin):
+    super(Sensor, self).__init__(board, pin)
+
+    self._pin.mode = pyfirmata.INPUT
+    self._pin.enable_reporting()
 
 class Led(Component):
 
@@ -46,27 +64,26 @@ def toggle(self):
   def blink(self, millis):
     self._interval = setInterval(self.toggle, millis)
 
-class Button(Component):
+class Buzzer(Led):
+  pass
+
+class Button(Sensor):
 
   def __init__(self, board, pin):
     super(Button, self).__init__(board, pin)
-
-    self._pin.mode = pyfirmata.INPUT
-    self._pin.enable_reporting()
-
-    self._old_value = self._pin.value
+    self._old_value = self.value
 
     self._board.on('data', self._handle_data)
 
   def _handle_data(self):
-    value = self._pin.value
+    value = self.value
 
     if self._old_value != value:
       self._old_value = value
       self._handle_state_changed()
 
   def _handle_state_changed(self):
-    if self._pin.value == False:
+    if self.value == False:
       self.emit('up')
     else:
       self.emit('down')

examples/buzzer.py

@@ -0,0 +1,29 @@
+#! /usr/bin/env python
+"""
+This is an example that demonstrates how to use a
+photoresistor to control a buzzer (piezo element)
+using breakfast_serial.  It assumes you have an
+photoresistor (or some equivalent analog input) 
+wired up to pin A0 and a buzzer on pin 8.
+"""
+from breakfast_serial import Arduino, Buzzer, Sensor, setInterval
+from time import sleep
+
+board = Arduino()
+buzzer = Buzzer(board, "8")
+sensor = Sensor(board, "A0")
+
+def loop():
+  value = sensor.value or 1 # value is initially None
+  value = value / 2
+
+  buzzer.on()
+  sleep(value)
+  buzzer.off()
+  sleep(value)
+
+setInterval(loop, 0)
+
+# Run an interactive shell so you can play (not required)
+import code
+code.InteractiveConsole(locals=globals()).interact()