Proof of Concept:

   - Code für Ansteuern der LEDs mit Aruino mithilfe von Adarfruit_Neopixel Library
   - Code für I2C-Kommunikation von TI Launchpad zu Arduino
   - Skizze der korrekten Verkabelung

code/README.md

+# Overview
+
+Werden wir mehrere Subfolder in code/ haben? Falls ja, wäre es nicht schlecht, hier eine kurze Übersicht über jeden
+Subfolder zu schreiben.
\ No newline at end of file

code/driveLedStripFromLaunchPadOverArduino/README.md

+# Function
+
+Drive a WS2812B-LED strip from an Arduino Uno. Set the colors via I2C from a TI CC1350 Launchpad connected to the Arduino Uno.
+
+This is a "prrof of concept" project to showcase how to drive the LED-strip and communicate via I2C from the launchpad to the Arduino.
+
+# Wiring
+
+A sketch of the wiring of the Launchpad, Arduino UNO, LED strip and the power source can be found in electric/wiring_LaunchpadArduinoLEDPowersource.png.
+
+# Prerequisites
+
+The Arduino relies on two libaries: Adafruit_Neopixel and Wire.
+
+- Wire handles the I2C communication. It should be preinstalled wit the ArduinoIDE.
+- Adafruit_Neopixel is a arduino driver library for the LED strip. It is not preinstalled. 
+    - To install the library,, follow the instructions specified here: https://github.com/adafruit/Adafruit_NeoPixel
+        	- download the latest release as a zip
+            - in the Arduino IDE, navigate to Sketch > Include Library > Add .ZIP Library
\ No newline at end of file

code/driveLedStripFromLaunchPadOverArduino/i2c_arduino_led/i2c_arduino_led.ino

+
+#include <Wire.h>
+#include <Adafruit_NeoPixel.h>
+
+/*
+  Dieses Programm verwendet die Adadruit Neopixel library, um eine WS2812B-LED-Leiste anzusteuern.
+
+  Die momentane Farbe wird durch ein per I2C verbundenes TI-Launchpad gesteuert. Dieses sendet eine Zahl 0-4 per I2C.
+
+  Die korrekte Verkabelung aller Komponenten (TI-Launchpad, Arduino UNO, Breadoard, LED-Strip, PowerSource)
+  ist in electric/wiring_LaunchpadArduinoLEDPowersource.png dargestellt.
+*/
+
+
+#define LED_DATA_PIN        6 
+#define NUMPIXELS 144 
+Adafruit_NeoPixel pixels(NUMPIXELS, LED_DATA_PIN, NEO_GRB + NEO_KHZ800);
+
+struct RGB{
+  uint8_t red;
+  uint8_t green;
+  uint8_t blue;
+};
+
+struct RGB possibleColors[5] = {
+    {3, 0, 0},
+    {0, 3, 3},
+    {3, 0, 3},
+    {0, 3, 0},
+    {0, 0, 3}
+};
+RGB currentColor = possibleColors[0];
+
+#define DELAYVAL 50 
+
+void setup() {
+  pixels.begin(); // INITIALIZE NeoPixel strip object
+
+  Wire.begin(4);                // join i2c bus with slave address 4. The sender must be aware of this adress!
+  Wire.onReceive(receiveEvent); // register event
+  Serial.begin(9600);           // start serial for output
+}
+
+void loop() {
+  pixels.clear(); // Set all pixel colors to 'off'
+
+  for(int i=0; i<NUMPIXELS; i++) { // For each pixel...
+
+    // pixels.Color() takes RGB values, from 0,0,0 up to 255,255,255
+    // careful with this value, even something like 150 hurts my eyes..
+    pixels.setPixelColor(i, pixels.Color(currentColor.red, currentColor.green, currentColor.blue));
+    if(i-15>=0){
+      pixels.setPixelColor(i-15, pixels.Color(0, 0, 0));
+    }
+
+    pixels.show();   // Send the updated pixel colors to the hardware.
+
+    delay(DELAYVAL); // Pause before next pass through loop
+  }
+}
+
+// function that executes whenever data is received from master
+// this function is registered as an event, see setup()
+void receiveEvent(int howMany)
+{
+  Serial.println("Received I2C data!");
+  uint8_t x = Wire.read();    // receive byte as an integer
+  Serial.println(x);         // print the integer
+  if(x>4){
+    Serial.println("Invalid number received! Only numbers 0-4 are valid");
+  }
+  else{
+    currentColor =  possibleColors[x];
+  }
+}

code/driveLedStripFromLaunchPadOverArduino/launchpadToArduino.c

+
+
+#include <unistd.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#include <ti/drivers/GPIO.h>
+#include <ti/drivers/I2C.h>
+#include "Board.h"
+
+/*
+ * Dieses Programm sendet eine Zahl aus der Menge {0, 1, 2, 3, 4} per I2C vom TI-Launchpad an demn Arduino.
+ * Durch Dr�cken des linken Buttons wechselt man die zu sendende Zahl.
+ * Druch Dr�cken des rechten Buttons l�st man das Senden der Zahl per I2C aus.
+ *
+ * Wichtig:
+ * -  Die korrekte Verkabelung der beiden Boards findet man im Repo in electric/wiring_LaunchpadArduinoLEDPowersource.png
+ *    - f�r den Arduino UNO gilt immer: SDA ist A4, SCL ist A5
+ *    - f�r die Pinbelegung des TI CC1350 Launchpad gilt das, was in CC1350LAUNCH.h steht (zu finden mit z.B. strg+F I2C)
+ *        - kann von Projekt zu Projekt anders sein, also immer doublechecken bei neuem Projekt
+ *        - f�r dieses Projekt: SCL ist DI04 und SDA ist DI05
+ * - Die hier gesetzte I2C-Slaveadresse muss mit der im Arduinocode gesetzten Adresse (per Wire.begin(x)) �bereinstimmen
+ */
+
+
+void gpioButton0Callback(uint_least8_t index);
+void gpioButton1Callback(uint_least8_t index);
+void configureGPIOButtons();
+void configureLEDs();
+void setupI2CCommunication();
+
+
+/* --------- global variables begin --------- */
+// program logic
+uint8_t numberToSend = 0;
+bool shouldSendI2CMessage = false;
+
+
+// I2C
+I2C_Handle      i2c;
+I2C_Params      i2cParams;
+I2C_Transaction i2cTransaction;
+uint8_t         i2cTransmitBuffer[1] = {0};
+
+/* --------- global variables end ---------*/
+
+
+void gpioButton0Callback(uint_least8_t index)
+{
+    numberToSend = (numberToSend+1) % 5;
+}
+
+void gpioButton1Callback(uint_least8_t index)
+{
+    shouldSendI2CMessage = true;
+}
+
+
+void *mainThread(void *arg0)
+{
+
+
+    GPIO_init();
+    I2C_init();
+    configureLEDs();
+    configureGPIOButtons();
+
+    setupI2CCommunication();
+
+
+    while(1){
+        if(shouldSendI2CMessage){
+            i2cTransmitBuffer[0] = numberToSend;
+            bool success = I2C_transfer(i2c, &i2cTransaction);
+            if(success){
+                // toggle green
+                GPIO_toggle(Board_GPIO_LED1);
+                sleep(1);
+                GPIO_toggle(Board_GPIO_LED1);
+             }
+            else{
+                // toggle red
+                GPIO_toggle(Board_GPIO_LED0);
+                sleep(1);
+                GPIO_toggle(Board_GPIO_LED0);
+            }
+            shouldSendI2CMessage = false;
+            sleep(1);
+        }
+   }
+
+     //I2C_close(i2c);
+}
+
+void configureGPIOButtons(){
+    // Configure buttons
+    GPIO_setConfig(Board_GPIO_BUTTON0, GPIO_CFG_IN_PU | GPIO_CFG_IN_INT_FALLING);
+    GPIO_setConfig(Board_GPIO_BUTTON1, GPIO_CFG_IN_PU | GPIO_CFG_IN_INT_FALLING);
+
+    /* install Button callback */
+    GPIO_setCallback(Board_GPIO_BUTTON0, gpioButton0Callback);
+    GPIO_setCallback(Board_GPIO_BUTTON1, gpioButton1Callback);
+
+    GPIO_enableInt(Board_GPIO_BUTTON0);
+    GPIO_enableInt(Board_GPIO_BUTTON1);
+}
+
+void configureLEDs(){
+   GPIO_setConfig(Board_GPIO_LED0, GPIO_CFG_OUT_STD | GPIO_CFG_OUT_LOW);
+   GPIO_setConfig(Board_GPIO_LED1, GPIO_CFG_OUT_STD | GPIO_CFG_OUT_LOW);
+}
+
+void setupI2CCommunication(){
+    // Erzeuge I2C "Objekt"
+    I2C_Params_init(&i2cParams);
+    i2cParams.bitRate = I2C_100kHz;
+    i2cParams.transferMode = I2C_MODE_BLOCKING;
+    i2c = I2C_open(Board_I2C0, &i2cParams);
+    if (i2c == NULL) {
+       while (1);
+    }
+
+    // die I2C-Slaveadresse, wird im Arduino-Code gesetzt
+    uint8_t arduinoSlaveAdress = 4;
+    i2cTransaction.slaveAddress = arduinoSlaveAdress;
+
+
+    // mit writeCount bzw readCount wird festgelegt, wie vile Bytes per I2C geschrieben bzw gelesen werden
+    // da der Arduino nur Befehle erh�lt und mann nie vom Arduino lesen muss, ist read count 0
+    i2cTransaction.writeBuf = i2cTransmitBuffer;
+    i2cTransaction.writeCount = 1;
+    i2cTransaction.readCount = 0;
+}
+
+