Updated ReadMe with API

Author: dcyoung

README.md

@@ -74,4 +74,88 @@ bool bSuccess = device.stopScanning();
 ```
 
 
+# API
 
+```c++
+Sweep(Stream &serial)
+```
+
+Constructs a sweep device on the provided Stream object.
+
+```c++
+bool bIsScanning
+```
+
+True if the device is currently scanning.
+
+```c++
+bool startScanning()
+```
+Signals the sweep device to start scanning. Initiates an indefinite stream of individual sensor readings until `stopScanning()` is called. 
+During an active data stream, any attempt to communicate with the device other than `stopScanning()` will fail.
+
+
+```c++
+bool stopScanning()
+```
+
+Signals the sweep device to stop scanning.
+
+```c++
+bool getReading(ScanPacket &reading)
+```
+
+Reads a single sensor reading from the serial buffer. Must be called frequently enough to keep up with the data stream.
+
+```c++
+struct ScanPacket
+{
+    bool bIsSync;           // 1 -> first reading of new scan, 0 otherwise
+    float angle;            // degrees
+    uint16_t distance;      // cm
+    uint8_t signalStrength; // 0:255, higher is better
+}
+```
+
+Structure representing a single sensor reading (ranging). ie: a full 360deg scan would be composed of many such readings.
+
+```c++
+int32_t getMotorSpeed()
+```
+
+Returns the current motor speed setting in HZ
+
+```c++
+bool setMotorSpeed(const uint8_t motorSpeedCode[2])
+
+// Available Codes
+MOTOR_SPEED_CODE_1_HZ
+MOTOR_SPEED_CODE_2_HZ
+MOTOR_SPEED_CODE_3_HZ
+MOTOR_SPEED_CODE_4_HZ
+MOTOR_SPEED_CODE_5_HZ
+MOTOR_SPEED_CODE_6_HZ
+MOTOR_SPEED_CODE_7_HZ
+MOTOR_SPEED_CODE_8_HZ
+MOTOR_SPEED_CODE_9_HZ
+MOTOR_SPEED_CODE_10_HZ
+```
+
+Adjusts the motor speed setting to the provided code. Recommend users pass one of the const codes defined by library:
+
+```c++
+int32_t getSampleRate()
+```
+
+Returns the current sample rate setting in HZ.
+
+```c++
+bool setSampleRate(const uint8_t sampleRateCode[2])
+
+// Available Codes
+SAMPLE_RATE_CODE_500_HZ
+SAMPLE_RATE_CODE_750_HZ
+SAMPLE_RATE_CODE_1000_HZ
+```
+
+Adjusts the sample rate setting to the provided code. Recommend users pass one of the const codes defined by library: