/*
/*******************************************************************************
                                      uS/OS-II v2.8
文 件 名  : os_cpu_c.c
作    者  : czn
版    本  : v1.0
********************************************************************************
*/
#define  OS_CPU_GLOBALS
#include "includes.h"

/*
*******************************************************************************
                                OSTaskStkInit()
功能描述: 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.
參    數: task      is a pointer to the task code
          p_arg     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
                    a 'free' entry on the task stack.  If OS_STK_GROWTH is set to 1 then 
                    'ptos' will contain the HIGHEST valid address of the stack.  Similarly, if
                    OS_STK_GROWTH is set to 0, the 'ptos' will contains the LOWEST valid address
                    of the stack.
          opt       specifies options that can be used to alter the behavior of OSTaskStkInit().
                    (see uCOS_II.H for OS_TASK_OPT_???).
說    明: Interrupts are enabled when your task starts executing.
*******************************************************************************
*/
OS_STK *OSTaskStkInit(void (*task)(void *p_arg),void *p_arg, OS_STK *ptos, INT16U opt) reentrant
{
    OS_STK *stk;

    p_arg = p_arg;
    opt    = opt;
    stk    = (OS_STK *)ptos;
    *stk++ = 15;                                /*用戶堆棧長度              */
    *stk++ = (INT16U)task & 0xFF;               /*任務地址低8位             */
    *stk++ = (INT16U)task >> 8;                 /*任務地址高8位             */
    *stk++ = 0x00;                              /*PSW                       */
    *stk++ = 0x0A;                              /*ACC                       */
    *stk++ = 0x0B;                              /*B                         */
    *stk++ = 0x00;                              /*DPL                       */
    *stk++ = 0x00;                              /*DPH                       */
    *stk++ = 0x00;                              /*R0                        */
    
	/*R3、R2、R1用于傳遞任務參數ppdata，其中R3代表存儲器類型，R2為高字節偏移，R1為低字節位移。*/
	/*通過分析KEIL匯編，了解到任務的void *ppdata參數恰好是用R3、R2、R1傳遞，不是通過虛擬堆棧。*/
    *stk++ = (INT16U)p_arg & 0xFF;             /*R1                        */
    *stk++ = (INT16U)p_arg >> 8;               /*R2                        */
    *stk++ = 0x01;                              /*R3  XDATA，存儲器類型為1  */

    *stk++ = 0x04;                              /*R4                        */
    *stk++ = 0x05;                              /*R5                        */
    *stk++ = 0x06;                              /*R6                        */
    *stk++ = 0x07;                              /*R7                        */
                                                /*不用保存SP，任務切換時根據用戶堆棧長度計算得出。*/    
    *stk++ = (INT16U) (ptos+MaxStkSize) >> 8;   /*?C_XBP 仿真堆棧指針高8位  */
    *stk++ = (INT16U) (ptos+MaxStkSize) & 0xFF; /*?C_XBP 仿真堆棧指針低8位  */

    return ((void *)ptos);
}
/*
*******************************************************************************
                                OSTaskCreateHook()
功能描述: This function is called when a task is created.
參    數: ptcb   is a pointer to the task control block of the task being created.
說    明: 1) Interrupts are disabled during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 
void OSTaskCreateHook(OS_TCB *ptcb) reentrant
{
    ptcb = ptcb;                 /* Prevent compiler warning                 */
}
#endif
/*
*******************************************************************************
                                OSTaskDelHook()
功能描述: This function is called when a task is deleted.
參    數: ptcb   is a pointer to the task control block of the task being deleted.
說    明: 1) Interrupts are disabled during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 
void OSTaskDelHook(OS_TCB *ptcb) reentrant
{
    ptcb = ptcb;                 /* Prevent compiler warning                 */
}
#endif
/*
*******************************************************************************
                                OSTaskSwHook()
功能描述: This function is called when a task switch is performed.  This allows you to perform other
          operations during a context switch.
參    數: none
說    明: 1) Interrupts are disabled during this call.
          2) It is assumed that the global pointer 'OSTCBHighRdy' points to the TCB of the task that
             will be 'switched in' (i.e. the highest priority task) and, 'OSTCBCur' points to the 
             task being switched out (i.e. the preempted task).
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 
void OSTaskSwHook(void) reentrant
{
}
#endif
/*
*******************************************************************************
                                OSTaskIdleHook()
功能描述: This function is called by the idle task.  This hook has been added to allow you to do  
          such things as STOP the CPU to conserve power.
參    數: none
說    明: 1) Interrupts are enabled during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 && OS_VERSION >= 251
void  OSTaskIdleHook (void)reentrant
{
}
#endif
/*
*******************************************************************************
                                OSTaskStatHook()
功能描述: This function is called every second by uC/OS-II's statistics task.  This allows your 
          application to add functionality to the statistics task.
參    數: none
說    明:
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 
void OSTaskStatHook(void) reentrant
{
}
#endif
/*
*******************************************************************************
                                OSTimeTickHook()
功能描述: This function is called every tick.
參    數: none
說    明: 1) Interrupts may or may not be ENABLED during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0
void OSTimeTickHook (void) reentrant
{
}
#endif
/*
*******************************************************************************
                                OSInitHookBegin()
功能描述: This function is called by OSInit() at the beginning of OSInit().
參    數: none
說    明: 1) Interrupts should be disabled during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 && OS_VERSION > 203
void  OSInitHookBegin (void) reentrant
{
}
#endif
/*
*******************************************************************************
                                OSInitHookEnd()
功能描述: This function is called by OSInit() at the beginning of OSInit().
參    數: none
說    明: 1) Interrupts should be disabled during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 && OS_VERSION > 203
void  OSInitHookEnd (void) reentrant
{
}
#endif
/*
*******************************************************************************
                                OSTCBInitHook()
功能描述: This function is called by OS_TCBInit() after setting up most of the TCB.
參    數: ptcb    is a pointer to the TCB of the task being created.
說    明: 1) Interrupts may or may not be ENABLED during this call.
*******************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0 && OS_VERSION > 203
void  OSTCBInitHook (OS_TCB *ptcb) reentrant
{
    ptcb = ptcb;                 /* Prevent Compiler warning                 */
}
#endif