Help in rtos embedded systems

[dhivyadurga]

hai everybody,...
we run the program for lcd display using uCOS-II in lpc2148 arm7 kit. we created 3 tasks which are having different priorities. Depending upon the priority the 3 tasks are running,... but it runs only one time. we want to run the tasks continuously. that is, after the completion of third task the control should go to the first task and run depends on the priority,... what is the problem in our code???
if anyone know, pls send us reply......

our code is given below..
thank you..

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Code C - [expand]
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void main()
{
  BSP_IntDisAll();
  OSInit();
  
  
  OSTaskCreate(Task1, 0, &Task1stk[99], 1);
 
  OSTaskCreate(Task2, 0, &Task2stk[99], 3); 
 
  OSTaskCreate(Task3, 0, &Task3stk[99], 2);
 
  //OSTaskCreateExt (Task1,0,&Task1stk[99],1,100,0,100,0,0x0000u);
  SemA=OSSemCreate(1);
  //SemB=OSSemCreate(1);
   OSStart();
 }
 
 
void Task1(void *pdata)
{
   lcd_init();  
   auto OS_TCB data;
   auto INT8U  err;
   OSTaskQuery(OS_PRIO_SELF, &data);
   
   while(1)
   {
    OSSemPend(SemA, 1, &err);
    lcd_write_control(0x01);                            // Clear Display  (Clear Display,Set DD RAM Address=0) 
    goto_cursor(0x00);                                  // Set Cursor Line-1
    lcd_print("LCDDEMOPRGM");                                                       // Display LCD Line-1   
    OSSemPost(SemA);
    OSTimeDlyHMSM(0,0,0,100);
   }
}
 
 
 
void Task2(void *pdata)
{
   lcd_init();      
   auto OS_TCB data;
   auto INT8U  err;
   OSTaskQuery(OS_PRIO_SELF, &data);
   
  while(1)
  {
    OSSemPend(SemA, 0, &err);
    lcd_write_control(0x01);                            // Clear Display  (Clear Display,Set DD RAM Address=0) 
    goto_cursor1(0X00);                                 // Set Cursor Line-1
    lcd_print("SUCCESS ");                  // Display LCD Line-1  
    OSSemPost(SemA);
    OSTimeDlyHMSM(0,0,0,100);
  }
}
 
void Task3(void *pdata)
{
 
  lcd_init();   // Initial LCD
  auto OS_TCB data;
   auto INT8U  err;
   OSTaskQuery(OS_PRIO_SELF, &data);
   
  while(1)
  {
    OSSemPend(SemA, 0, &err);
    lcd_write_control(0x01);                            // Clear Display  (Clear Display,Set DD RAM Address=0) 
    goto_cursor(0x00);                                  // Set Cursor Line-1
    lcd_print("TASK3 executed now");
    OSSemPost(SemA);
    OSTimeDlyHMSM(0,0,0,100);
 }
}

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[willis...]

Greetings,

At first glance I already see a possible problem. I believe that uC/OS-II reserves the three highest and three lowest priorities for system tasks. I would try making your tasks priorities 4, 5, and 6, respectively.

-Willis