hsch51.lst

时间触发嵌入式系统设计模式:使用8051系列微控制器开发可靠应用

C51 COMPILER V6.10  HSCH51                                                                 04/19/2001 11:26:09 PAGE 1   


C51 COMPILER V6.10, COMPILATION OF MODULE HSCH51
OBJECT MODULE PLACED IN .\HSCH51.OBJ
COMPILER INVOKED BY: C:\KEIL\C51\BIN\C51.EXE .\HSCH51.C OPTIMIZE(6,SPEED) BROWSE DEBUG OBJECTEXTEND

stmt level    source

   1          /*------------------------------------------------------------------*-
   2          
   3             hSCH51.C (v1.00) 
   4          
   5            ------------------------------------------------------------------
   6          
   7             /// HYBRID SCHEDULER CORE ///
   8          
   9             *** THESE ARE THE CORE SCHEDULER FUNCTIONS ***
  10             --- These functions may be used with all 8051 devices ---
  11          
  12             *** hSCH_MAX_TASKS *must* be set by the user ***
  13             --- see "Sch51.h" ---
  14          
  15             *** Includes power-saving mode ***
  16             --- You *MUST* confirm that the power-down mode is adapted ---
  17             --- to match your chosen device (usually only necessary with 
  18             --- Extended 8051s, such as c515c, c509, etc ---
  19          
  20             COPYRIGHT
  21             ---------
  22          
  23             This code is from the book:
  24          
  25             PATTERNS FOR TIME-TRIGGERED EMBEDDED SYSTEMS by Michael J. Pont 
  26             [Pearson Education, 2001; ISBN: 0-201-33138-1].
  27          
  28             This code is copyright (c) 2001 by Michael J. Pont.
  29           
  30             See book for copyright details and other information.
  31          
  32          -*------------------------------------------------------------------*/
  33          
  34          #include "Main.h"
  35          #include "Port.h"
  36          
  37          #include "hSch51.h"
  38          
  39          // ------ Public variable definitions ------------------------------
  40          
  41          // The array of tasks
  42          sTaskH hSCH_tasks_G[hSCH_MAX_TASKS];
  43          
  44          // Used to display the error code
  45          // See Main.H for details of error codes
  46          // See Port.H for details of the error port
  47          tByte Error_code_G = 0;
  48          
  49          // ------ Private function prototypes ------------------------------
  50          
  51          static void hSCH_Go_To_Sleep(void);
  52          
  53          // ------ Private variables ----------------------------------------
  54          
  55          // Keeps track of time since last error was recorded (see below)
C51 COMPILER V6.10  HSCH51                                                                 04/19/2001 11:26:09 PAGE 2   

  56          static tWord Error_tick_count_G;
  57          
  58          // The code of the last error (reset after ~1 minute)
  59          static tByte Last_error_code_G;
  60          
  61          
  62          /*------------------------------------------------------------------*-
  63          
  64            hSCH_Dispatch_Tasks()
  65          
  66            This is the 'dispatcher' function.  When a task (function)
  67            is due to run, hSCH_Dispatch_Tasks() will run it.
  68            This function must be called (repeatedly) from the main loop.
  69          
  70          -*------------------------------------------------------------------*/
  71          void hSCH_Dispatch_Tasks(void) 
  72             {
  73   1         tByte Index;
  74   1      
  75   1         // Dispatches (runs) the next task (if one is ready)
  76   1         for (Index = 0; Index < hSCH_MAX_TASKS; Index++)
  77   1            {
  78   2            // Only dispatching co-operative tasks
  79   2            if ((hSCH_tasks_G[Index].Co_op) && (hSCH_tasks_G[Index].RunMe > 0)) 
  80   2               {
  81   3               (*hSCH_tasks_G[Index].pTask)();  // Run the task
  82   3      
  83   3               hSCH_tasks_G[Index].RunMe -= 1;   // Reset / reduce RunMe flag
  84   3      
  85   3               // Periodic tasks will automatically run again
  86   3               // - if this is a 'one shot' task, remove it from the array
  87   3               if (hSCH_tasks_G[Index].Period == 0)
  88   3                  {
  89   4                  // Faster than call to delete task
  90   4                  hSCH_tasks_G[Index].pTask = 0;
  91   4                  }
  92   3               }
  93   2            }
  94   1      
  95   1         // Report system status
  96   1         hSCH_Report_Status();  
  97   1      
  98   1         // The scheduler enters idle mode at this point 
  99   1         hSCH_Go_To_Sleep();          
 100   1         }
 101          
 102          /*------------------------------------------------------------------*-
 103          
 104            hSCH_Add_Task()
 105          
 106            Causes a task (function) to be executed at regular intervals 
 107            or after a user-defined delay
 108          
 109            Fn_P  - The name of the function which is to be scheduled.
 110                    NOTE: All scheduled functions must be 'void, void' -
 111                    that is, they must take no parameters, and have 
 112                    a void return type. 
 113                             
 114            Del   - The interval (TICKS) before the task is first executed
 115          
 116            Rep   - If 'Rep' is 0, the function is only called once,
 117                    at the time determined by 'Del'.  If Rep is non-zero,
C51 COMPILER V6.10  HSCH51                                                                 04/19/2001 11:26:09 PAGE 3   

 118                    then the function is called repeatedly at an interval
 119                    determined by the vakue of Rep (see below for examples
 120                    that should help clarify this).
 121          
 122            Co-op - Set to 1 if it a co-op task; 0 if pre-emptive
 123          
 124            RETN:   The position in the task array at which the task has been added.
 125                    If the return value is hSCH_MAX_TASKS then the task could not be
 126                    added to the array (there was insufficient space).  If the
 127                    return value is < hSCH_MAX_TASKS, then the task was added 
 128                    successfully.  
 129          
 130                    Note: this return value may be required, if a task is
 131                    to be subsequently deleted - see hSCH_Delete_Task().
 132          
 133          
 134            EXAMPLES:
 135          
 136            Task_ID = hSCH_Add_Task(Do_X,1000,0,0);
 137            Causes the function Do_X() to be executed once after 1000 ticks.
 138            (Pre-emptive task)          
 139          
 140            Task_ID = hSCH_Add_Task(Do_X,0,1000,1);
 141            Causes the function Do_X() to be executed regularly, every 1000 ticks.            
 142            (co-operative task)          
 143          
 144            Task_ID = hSCH_Add_Task(Do_X,300,1000,0);
 145            Causes the function Do_X() to be executed regularly, every 1000 ticks.
 146            Task will be first executed at T = 300 ticks, then 1300, 2300, etc.            
 147            (Pre-emptive task)          
 148           
 149          -*------------------------------------------------------------------*/
 150          tByte hSCH_Add_Task(void (code* Fn_p)(), // Task function pointer
 151                             tWord   Del,    // Num ticks 'til task first runs 
 152                             tWord   Per,    // Num ticks between repeat runs
 153                             bit     Co_op)  // Co_op / pre_emp
 154             {
 155   1         tByte Index = 0;
 156   1         
 157   1         // First find a gap in the array (if there is one)
 158   1         while ((hSCH_tasks_G[Index].pTask != 0) && (Index < hSCH_MAX_TASKS))
 159   1            {
 160   2            Index++;
 161   2            } 
 162   1         
 163   1         // Have we reached the end of the list?   
 164   1         if (Index == hSCH_MAX_TASKS)
 165   1            {