add force_read argument fix namedtuples in values

Author: jfurcean

adafruit_nunchuk.py

@@ -49,10 +49,16 @@ class Nunchuk:
     :type i2c_read_delay: float, optional
     """
 
-    def __init__(self, i2c, address=0x52, i2c_read_delay=0.002):
+    _Values = namedtuple("Values", ("joystick", "buttons", "acceleration"))
+    _Joystick = namedtuple("Joystick", ("x", "y"))
+    _Buttons = namedtuple("Buttons", ("C", "Z"))
+    _Acceleration = namedtuple("Acceleration", ("x", "y", "z"))
+
+    def __init__(self, i2c, address=0x52, i2c_read_delay=0.002, force_read=True):
         self.buffer = bytearray(8)
         self.i2c_device = I2CDevice(i2c, address)
         self._i2c_read_delay = i2c_read_delay
+        self._force_read = force_read
         time.sleep(_I2C_INIT_DELAY)
         with self.i2c_device as i2c_dev:
             # turn off encrypted data
@@ -65,33 +71,44 @@ def __init__(self, i2c, address=0x52, i2c_read_delay=0.002):
     def values(self):
         """Return named tuple of all the input values."""
         self.read_data()
-        (sx, sy), bc, bz, (ax, ay, az) = (  # pylint: disable=invalid-name
-            self.joystick,
-            self.button_C,
-            self.button_Z,
-            self.acceleration,
+        temp_force_read = self._force_read
+        self._force_read = False
+        values = self._Values(
+            self._Joystick(self.joystick[0], self.joystick[1]),
+            self._Buttons(self.button_C, self.button_Z),
+            self._Acceleration(
+                self.acceleration[0], self.acceleration[1], self.acceleration[2]
+            ),
         )
-        Values = namedtuple("Values", "sx sy bc bz ax ay az")
-        return Values(sx, sy, bc, bz, ax, ay, az)
+        self._force_read = temp_force_read
+        return values
 
     @property
     def joystick(self):
         """Return tuple of current joystick position."""
+        if self._force_read:
+            self.read_data()
         return self.buffer[0], self.buffer[1]
 
     @property
     def button_C(self):  # pylint: disable=invalid-name
         """Return current pressed state of button C."""
+        if self._force_read:
+            self.read_data()
         return not bool(self.buffer[5] & 0x02)
 
     @property
     def button_Z(self):  # pylint: disable=invalid-name
         """Return current pressed state of button Z."""
+        if self._force_read:
+            self.read_data()
         return not bool(self.buffer[5] & 0x01)
 
     @property
     def acceleration(self):
         """Return 3 tuple of accelerometer reading."""
+        if self._force_read:
+            self.read_data()
         x = (self.buffer[5] & 0xC0) >> 6
         x |= self.buffer[2] << 2
         y = (self.buffer[5] & 0x30) >> 4

examples/nunchuk_simpletest.py

@@ -8,11 +8,11 @@
 nc = adafruit_nunchuk.Nunchuk(board.I2C())
 
 while True:
-    values = nc.values
-    print("joystick = {},{}".format(values.sx, values.sy))
-    print("accceleration ax={}, ay={}, az={}".format(values.ax, values.ay, values.az))
-    if values.bc:
+    joystick,buttons,acceleration = nc.values
+    print("joystick = {},{}".format(joystick.x, joystick.y))
+    print("accceleration ax={}, ay={}, az={}".format(acceleration.x, acceleration.y, acceleration.z))
+    if buttons.C:
         print("button C")
-    if values.bz:
+    if buttons.Z:
         print("button Z")
     time.sleep(0.5)