os_cpu_c.c

ucos-ii-at90S-icc-avr

/*
********************************************************************************
*                               uC/OS-II
*                          The Real-Time Kernel
* 
*                         AT90 Specific code
*
* File:			OS_CPU_C.C
* By:			
* Modified by:
* Revision:	
*
*
*
********************************************************************************
*/

#define  OS_CPU_GLOBALS
#include "includes.h"

/*
********************************************************************************
*                     INITIALIZE A TASK'S STACK
*
* Description:
*	This function is called by either OSTaskCreate() or OSTaskCreateExt() to
*	initialize the stack frame of the task being created. This function is
*	highly processor specific.
*
* Arguments:
*	task - 	is a pointer to the task code
*
*	pdata -	is a pointer to a user supplied data area that will be passed to the
*			 task when the task first executes.
*
*	ptos - 	is a pointer to the top of stack. It is assumed that 'ptos' points to
*			the highest valid address on the stack.
*
*	opt - 	specifies options that can be used to alter the behavior of 
			OSTaskStkInit(). (see uCOS_II.H for OS_TASK_OPT_???).
*
* Returns:
*	Always returns the location of the new top-of-stack' once the processor 
*	registers have been placed on the stack in the proper order.
*
* Note(s):
*	Interrupts are enabled when your task starts executing. You can change this 
* 	by setting the SREG to 0x00 instead. In this case, interrupts would be 
*	disabled upon task startup. The application code would be responsible for 
*	enabling interrupts at the beginning of the task code. You will need to 
*	modify OSTaskIdle() and OSTaskStat() so that they enable interrupts. Failure
*	to do this will make your system crash! The AVR return stack is placed 64 
*	bytes above the start of the (512 byte) stack. This provides 32 levels of 
*	function call nesting which should be more than enough for most applications
*	(see the "read.me" file for more info).
*
********************************************************************************
*/
OS_STK *OSTaskStkInit (void (*task)(void *pd),
						 void *pdata, OS_STK *ptos, INT16U opt){

    INT8U  *stk;
    INT8U  *stks;		// Temp. variable used for setting up AVR hardware stack
    INT16U tmp;


    opt     = opt;			// 'opt' is not used, prevent warning
    stk     = (INT8U *)ptos;		// Wandlung von ptos in Bytezeiger
	// AVR return stack ("hardware stack")
    //from IAR C
    //stks    = (INT8U *)(ptos)-(OS_TASK_DEF_STK_SIZE-64);/* AVR return stack ("hardware stack")          */
    //from ICC AVR C
    //stks    = (INT8U *)(ptos)-(OS_TASK_DEF_STK_SIZE-32);
    stks    = (INT8U *)(ptos)-(OS_TASK_DEF_STK_SIZE-64);

	// the function address has an extra level of indirection. Fetch the
    // actual address.
    //    
    tmp = *(INT16U const *)task;
   
	// 36 Bytes
    *stks-- = (INT8U)tmp;	//Put task start address on top of hardware stack
    *stks-- = (INT8U)(tmp >> 8);

    *stk-- = (INT8U)0x00;		// R0  = 0x00
    *stk-- = (INT8U)0x01; 
    *stk-- = (INT8U)0x02;
    *stk-- = (INT8U)0x03;
    *stk-- = (INT8U)0x04;
    *stk-- = (INT8U)0x05;
    *stk-- = (INT8U)0x06;
    *stk-- = (INT8U)0x07;
    *stk-- = (INT8U)0x08;
    *stk-- = (INT8U)0x09;
    *stk-- = (INT8U)0x10;
    *stk-- = (INT8U)0x11;
    *stk-- = (INT8U)0x12;
    *stk-- = (INT8U)0x13;
    *stk-- = (INT8U)0x14;
    *stk-- = (INT8U)0x15;
    tmp    = (INT16U)pdata;
    *stk-- = (INT8U)tmp;	//Simulate call to function with argument
    *stk-- = (INT8U)(tmp >> 8);
    *stk-- = (INT8U)0x18;
    *stk-- = (INT8U)0x19;
    *stk-- = (INT8U)0x20;
    *stk-- = (INT8U)0x21;
    *stk-- = (INT8U)0x22;
    *stk-- = (INT8U)0x23;
    *stk-- = (INT8U)0x24;
    *stk-- = (INT8U)0x25;
    *stk-- = (INT8U)0x26;
    *stk-- = (INT8U)0x27;
	// the heap pointer Y=R29:R28 will not be stored
    *stk-- = (INT8U)0x30;
    *stk-- = (INT8U)0x31;
    *stk-- = (INT8U)0x3B;
    *stk-- = (INT8U)0x80;	//SREG = Interrupts enabled

    tmp    = (INT16U)(stks);
    *stk-- = (INT8U)(tmp >> 8);
    *stk   = (INT8U)(tmp);
    return ((void *)stk);
}

#if OS_CPU_HOOKS_EN
/*
********************************************************************************
*                       TASK CREATION HOOK
*
* Description: This function is called when a task is created.
*
* Arguments:
*		ptcb is a pointer to the task control block of the task being created.
*
* Note(s):	1) Interrupts are disabled during this call.
********************************************************************************
*/
void OSTaskCreateHook (OS_TCB *ptcb)
{
    ptcb = ptcb;		// Prevent compiler warning
}


/*
********************************************************************************
*                      TASK DELETION HOOK
*
* Description: This function is called when a task is deleted.
*
* Arguments: 
*		ptcb is a pointer to the task control block of the task being deleted.
*
* Note(s):	1) Interrupts are disabled during this call.
********************************************************************************
*/
void OSTaskDelHook (OS_TCB *ptcb)
{
    ptcb = ptcb;		// Prevent compiler warning
}

/*
********************************************************************************
*                       STATISTIC TASK HOOK
*
* Description:
*	This function is called every second by uC/OS-II's statistics task.  This 
*	allows your application to add functionality to the statistics task.
*
* Arguments:	none
********************************************************************************
*/
void OSTaskStatHook (void)
{
}

/*
********************************************************************************
*                 TICK HOOK
*
* Description: This function is called every tick.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
********************************************************************************
*/
void OSTimeTickHook (void)
{
}
#endif

//by zhaowd
void Init_Timer1_CompareA()
{ 	    					   
    TCCR0       = 0x05;                                 /* Set TIMER0 prescaler to CLK/1024                 */
    TIMSK       = 0x02;                                 /* Enable TIMER0 overflow interrupt                 */
//    UBRR        = 23;                                   /* 19200 BAUD at 7.3728MHz                          */
//    MCUCR      |= 0x80;                                 /* Enable external RAM                              */
//    UCR         = 0x08;                                 /* Enable UART transmitter                          */
}
//*****************************************************************************
//			TickISR
//*****************************************************************************
// Init Timer/Counter2 fuer Takterzeugung
void TC2_Init (void){	
    Init_Timer1_CompareA();	
//    UBRR        = 23;                                   /* 19200 BAUD at 7.3728MHz                          */
//    MCUCR      |= 0x80;                                 /* Enable external RAM                              */
//    UCR         = 0x08;                                 /* Enable UART transmitter                          */
//    UartTxCount = 0;                                    /* Clear number of characters to send               */
//    UartTxRdPtr = 0;                                    /* Initialize transmit buffer read pointer          */
//    UartTxWrPtr = 0;                                    /* Initialize transmit buffer write pointer         */
	/**/
    //not SEI!!
	//SEI();
}