/**********************************************************************
* $Id$		abstract.txt 			
*//**
* @file		abstract.txt 
* @brief	Example description file
* @version	2.0
* @date		
* @author	NXP MCU SW Application Team/Micromint USA Support
*
* Copyright(C) 2010, NXP Semiconductor
* All rights reserved.
*
***********************************************************************
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* products. This software is supplied "AS IS" without any warranties.
* NXP Semiconductors assumes no responsibility or liability for the
* use of the software, conveys no license or title under any patent,
* copyright, or mask work right to the product. NXP Semiconductors
* reserves the right to make changes in the software without
* notification. NXP Semiconductors also make no representation or
* warranty that such application will be suitable for the specified
* use without further testing or modification.
**********************************************************************/
  
@Example description:
Purpose:
	This example describes how to change privilege to unprivilege mode and 
        vice vesa.
Process:
	CONTROL[0] register controls the privilege level for software execution 
        when the processor is in Thread mode. So, we can access to get/set 
        CONTROL[0] to change Thread mode privilege level.
		
	Out of reset, Thread mode is privilege.
	Read CONTROL[0] to check if it is truly privilege or not.
	If Thread mode is not privilege, so it's not compliant with Cortex-M3 
        Technical, the program will enter into infinite error loop. Then, set 
        CONTROL[0] = 1, changing Thread mode to unprivilege. Re-check by re-read
        CONTROL[0] again.
	A system service will be call __SCV(). In this exception mode, we can 
        switch back Thread mode into privilege 
	(Note that: When Thread mode has been changed from privilege to use, it 
                    cannot change ifself back to privilege. Only a handler can 
                    change the privilege of Thread mode. Handler mode is always
                    privilege.)
                    
	After call handler, get CONTROL[0] to check if it is truly privilege or 
        not. If not, program will enter to error loop.
		
	We use two LED to display status of Thread mode.
	LED1: turn on if Thread mode is privilege.
	LED2: turn on if Thread mode is unprivilege.
					
@Directory contents:
	\EWARM: includes EWARM (IAR) project and configuration files
	\Keil:	includes RVMDK (Keil)project and configuration files 
	
	lpc17xx_libcfg.h: Library configuration file - include needed driver 
        library for this example 
	makefile: Example's makefile (to build with GNU toolchain)
	priviledge.c: Main program

@How to run:		
Serial display configuration:(e.g: TeraTerm, Hyperterminal, Flash Magic...) 
	– 115200bps 
	– 8 data bit 
	– No parity 
	– 1 stop bit 
	– No flow control 
	
Running mode:
	This example can run on RAM/ROM mode.
					
Step to run:
	- Step 1: Build example.
	- Step 2: Burn hex file into board (if run on ROM mode)
	- Step 3: Connect COM1 on the Lincoln board to COM port on your computer
	- Step 4: Configure hardware and serial display as above instruction 
	- Step 5: Run example and observe on serial display
				+ Press '1' to change into unprivilege mode
				+ Press '2' to switch back to privilege mode
		
@Tip:
	- Open \EWARM\*.eww project file to run example on IAR
	- Open \RVMDK\*.uvproj project file to run example on Keil