;/*
;    FreeRTOS V8.2.0 - Copyright (C) 2014 Real Time Engineers Ltd.
;    All rights reserved
;
;
;    ***************************************************************************
;     *                                                                       *
;     *    FreeRTOS tutorial books are available in pdf and paperback.        *
;     *    Complete, revised, and edited pdf reference manuals are also       *
;     *    available.                                                         *
;     *                                                                       *
;     *    Purchasing FreeRTOS documentation will not only help you, by       *
;     *    ensuring you get running as quickly as possible and with an        *
;     *    in-depth knowledge of how to use FreeRTOS, it will also help       *
;     *    the FreeRTOS project to continue with its mission of providing     *
;     *    professional grade, cross platform, de facto standard solutions    *
;     *    for microcontrollers - completely free of charge!                  *
;     *                                                                       *
;     *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
;     *                                                                       *
;     *    Thank you for using FreeRTOS, and thank you for your support!      *
;     *                                                                       *
;    ***************************************************************************
;
;
;    This file is part of the FreeRTOS distribution.
;
;    FreeRTOS 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 modification to the GPL is included to allow you to
;    distribute a combined work that includes FreeRTOS without being obliged to
;    provide the source code for proprietary components outside of the FreeRTOS
;    kernel.  FreeRTOS 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 and the FreeRTOS license exception along with FreeRTOS; if not it
;    can be viewed here: http://www.freertos.org/a00114.html and also obtained
;    by writing to Richard Barry, contact details for whom are available on the
;    FreeRTOS WEB site.
;
;    1 tab == 4 spaces!
;
;    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.
;*/

#include "ISR_Support.h"

#define CS                    0xFFFFC
#define ES                    0xFFFFD

	PUBLIC    vPortYield
	PUBLIC    vPortStartFirstTask
	PUBLIC    vPortTickISR

	EXTERN    vTaskSwitchContext
	EXTERN    xTaskIncrementTick

; FreeRTOS yield handler.  This is installed as the BRK software interrupt
; handler.
    RSEG CODE:CODE
vPortYield:
	portSAVE_CONTEXT		        ; Save the context of the current task.
	call      vTaskSwitchContext    ; Call the scheduler to select the next task.
	portRESTORE_CONTEXT		        ; Restore the context of the next task to run.
	retb


; Starts the scheduler by restoring the context of the task that will execute
; first.
    RSEG CODE:CODE
vPortStartFirstTask:
	portRESTORE_CONTEXT	            ; Restore the context of whichever task the ...
	reti					        ; An interrupt stack frame is used so the task
                                    ; is started using a RETI instruction.

; FreeRTOS tick handler.  This is installed as the interval timer interrupt
; handler.
	 RSEG CODE:CODE
vPortTickISR:

	portSAVE_CONTEXT		       ; Save the context of the current task.
	call	xTaskIncrementTick     ; Call the timer tick function.
	cmpw	ax, #0x00
	skz
	call	vTaskSwitchContext     ; Call the scheduler to select the next task.
	portRESTORE_CONTEXT		       ; Restore the context of the next task to run.
	reti


; Install the interrupt handlers

	COMMON INTVEC:CODE:ROOT(1)
	ORG configTICK_VECTOR
	DW vPortTickISR

	COMMON INTVEC:CODE:ROOT(1)
	ORG 126
	DW vPortYield


      END