add Text to readme file

README.md

@@ -6,8 +6,17 @@ Pong game on Altera FPGA as exercise in Hardware-/Software-Codesign
 ![](images/data_graph.png)
 
 ## Programmablaufplan des C Programms
+Below images show flowcharts for all featured software functions.
+Fist chart feature the main game function. Subfunctions are described below.
+See:    - draw
+        - reset_positons
+        - reset_screen
+
+### Main function Flowchart
 ![](images/game_function_PAP.png)
 
+
+## Subfunctions  Flowcharts
 ![](images/draw.png)
 
 ![](images/reset_positions.png)