/*
	FreeRTOS.org V5.3.0 - Copyright (C) 2003-2009 Richard Barry.

	This file is part of the FreeRTOS.org distribution.

	FreeRTOS.org is free software; you can redistribute it and/or modify it
	under the terms of the GNU General Public License (version 2) as published
	by the Free Software Foundation and modified by the FreeRTOS exception.
	**NOTE** The exception to the GPL is included to allow you to distribute a
	combined work that includes FreeRTOS.org without being obliged to provide
	the source code for any proprietary components.  Alternative commercial
	license and support terms are also available upon request.  See the 
	licensing section of http://www.FreeRTOS.org for full details.

	FreeRTOS.org is distributed in the hope that it will be useful,	but WITHOUT
	ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
	more details.

	You should have received a copy of the GNU General Public License along
	with FreeRTOS.org; if not, write to the Free Software Foundation, Inc., 59
	Temple Place, Suite 330, Boston, MA  02111-1307  USA.


	***************************************************************************
	*                                                                         *
	* Get the FreeRTOS eBook!  See http://www.FreeRTOS.org/Documentation      *
	*                                                                         *
	* This is a concise, step by step, 'hands on' guide that describes both   *
	* general multitasking concepts and FreeRTOS specifics. It presents and   *
	* explains numerous examples that are written using the FreeRTOS API.     *
	* Full source code for all the examples is provided in an accompanying    *
	* .zip file.                                                              *
	*                                                                         *
	***************************************************************************

	1 tab == 4 spaces!

	Please ensure to read the configuration and relevant port sections of the
	online documentation.

	http://www.FreeRTOS.org - Documentation, latest information, license and
	contact details.

	http://www.SafeRTOS.com - A version that is certified for use in safety
	critical systems.

	http://www.OpenRTOS.com - Commercial support, development, porting,
	licensing and training services.
*/

#ifndef PORT_ASM_H
#define PORT_ASM_H

typedef void tskTCB;
extern volatile tskTCB * volatile pxCurrentTCB;
extern void vTaskSwitchContext( void );

/*
 * Saves the stack pointer for one task into its TCB, calls
 * vTaskSwitchContext() to update the TCB being used, then restores the stack
 * from the new TCB read to run the task.
 */
void portEND_SWITCHING_ISR( void );

/*
 * Load the stack pointer from the TCB of the task which is going to be first
 * to execute.  Then force an IRET so the registers and IP are popped off the
 * stack.
 */
void portFIRST_CONTEXT( void );

#define portEND_SWITCHING_ISR()											\
							asm { mov	bx, [pxCurrentTCB]			}   \
                            asm { mov	word ptr [bx], sp			}	\
							asm { call  far ptr vTaskSwitchContext	}	\
							asm { mov	bx, [pxCurrentTCB]			}	\
							asm { mov	sp, [bx]					}

#define portFIRST_CONTEXT()											\
							asm { mov	bx, [pxCurrentTCB]			}	\
							asm { mov	sp, [bx]					}	\
							asm { pop	bp							}	\
							asm { pop	di							}	\
							asm { pop	si							}	\
   							asm { pop	ds							}	\
   							asm { pop	es							}	\
							asm { pop	dx							}	\
							asm { pop	cx							}	\
							asm { pop	bx							}	\
							asm { pop	ax							}	\
							asm { iret								}


#endif

