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diff --git a/System_Python/system_BASE_2371.py b/System_Python/system_BASE_2371.py
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+#!/usr/bin/env python
+from motor import Motor
+from encoder import Encoder
+import math
+
+# IO pin definitions
+### Motor pins
+motor_speed_pin = 17
+motor_forward_pin = 27
+motor_reverse_pin = 22
+### Encoder pins (shared by both encoders)
+encoder_clock_pin = 2
+encoder_data_pin = 3
+### Angular encoder pins
+encoder_angular_cs_pin = 4
+### Linear encoder pins
+encoder_linear_cs_pin = 5
+
+
+# System Class
+# This is the primary interface a student will use to control the pendulum.
+class System:
+    def __init__(self):
+        # Initialize the motor.
+        self.motor = Motor(motor_speed_pin, motor_forward_pin, motor_reverse_pin)
+        # Initialize the angular encoder.
+        self.encoder_angular = Encoder(encoder_clock_pin, encoder_angular_cs_pin, encoder_data_pin)
+        self.encoder_angular.set_zero()
+        # Initialize the linear encoder.
+        self.encoder_linear = Linear_Encoder(encoder_clock_pin, encoder_linear_cs_pin, encoder_data_pin)
+        self.encoder_linear.set_zero()
+    # END __init__()
+    
+    # Get the values of the encoders to determine the angular and linear position of the pendulum.
+    # Values are returned as a tuple: (angle, linear).
+    ### angle: 0 indicates the pendulum is exactly straight up.
+    #####      180 or -180 indicate the pendulum is exactly straight down.
+    #####      Positive values indicate the pendulum is leaning to the right.
+    #####      Negative values indicate the pendulum is leaning to the left.
+    ### linear: 0 indicates the pendulum is exactly in the middle of the track.
+    #####       Positive values indicate the pendulum is right-of-center.
+    #####       Negative values indicate the pendulum is left-of-center.
+    def measure(self):
+        angular_position = self.encoder_angular.read_position('Degrees')
+        if angular_position > 180:
+            angular_position = angular_position - 360
+        #linear_position = self.encoder_linear.read_position()
+        linear_position = 0
+        return (angular_position, linear_position)
+    # END measure()
+    
+    # Adjust the pendulum's linear position using the motor.
+    ### speed: Acceptable values range from -100 to 100 (as a percentage), with 100/-100 being the maximum adjustment speed.
+    #####      Negative values will move the pendulum to the left.
+    #####      Positive values will move the pendulum to the right.
+    def adjust(self, speed):
+        # cap the speed inputs
+        if speed > 100.0:
+            speed = 100.0
+        if speed < -100.0:
+            speed = -100.0
+        # change the motor speed
+        # TODO: Make sure the motor is oriented so that positive speed the correct direction (same for negative). Change the values otherwise.
+        self.motor.coast()
+        self.motor.move(speed)
+    # END adjust()
+# END System
+
+# Linear Encoder class
+# This class is to help with using an absolute encoder for linear position sensing as assembled in the physical system.
+# The function definitions here are the same as with the regular encoder (pseudo-interface).
+class Linear_Encoder:
+    DIAMETER = 4.0 # MEASURE THIS
+    
+    def __init__(self, clk_pin, cs_pin, data_pin):
+        self.encoder = Encoder(clk_pin, cs_pin, data_pin)
+        self.set_zero()
+    def set_zero(self):
+        # Set the zero position for the encoder
+        self.encoder.set_zero()
+        # Reset the internal position counter
+        self.rotations = 0
+        self.last_position = 0
+    def read_position(self):
+        # Read the position of the encoder 
+        position = self.encoder.read_position('Raw')
+        # Compare to last known position
+        # NOTE: For now, assume that we are moving the smallest possible distance (i.e. 5 -> 1 is -4, not 1020)
+        if position - self.last_position > 0:
+            if position < 512 and self.last_position > 512:
+                # We are moving to the right (positive) and have completed a new rotation
+                self.rotations = self.rotations + 1
+        else:
+            if position > 512 and self.last_position < 512:
+                # We are moving to the left (negative) and have completed a new rotation
+                self.rotations = self.rotations - 1
+        # Save the last position for the next calculation
+        self.last_position = position
+            
+        # compute the position based on the system parameters
+        # linear position = (2pi*r)(n) + (2pi*r)(position/1024) = (2pi*r)(n + position/1024) = (pi*d)(n + position/1024)
+        return (math.pi*DIAMETER)*(self.rotations + position/1024)