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how do I get the string to be printed once

Posted by Angel Eyes on September 2, 2008
Hi in the below pasted code which I am running on a simulator (Skyeye ) , I see for the currentlyrunning task, it is printing out the string multiple times , since it is in the 'for' loop ,the output looks like this

T1
T1
T1
T1
the above goes on for sometime until it switches to the below output .

T2
T2
T2
T2
the above goes on for sometime until it switches back to T1. This repeats .

I am using preemptive multitasking ...

However in demos I see that the output comes out only once when a printf statement is used even in a for loop . How to block the printing after once ? I tried seaphores too but I do not see any change .

The code is pasted below ...

#include "S3C4510.h"
/* Standard includes. */
#include <stdlib.h>
#include <string.h>

/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"

/* Demo application includes. */
#include "partest.h"
#include "flash.h"
#include "integer.h"
#include "PollQ.h"
#include "comtest2.h"
#include "semtest.h"
#include "flop.h"
#include "dynamic.h"
#include "BlockQ.h"
#include "serial.h"
int counter = 0 ;
#define mainCHECK_TASK_PRIORITY 3
#define mainCHECK_TASK_PRIORITY1 3

static void vErrorChecks( void *pvParameters );

static void vErrorChecks1( void *pvParameters );

void timersetup (void );

int main(void)
{
int i;



xTaskCreate( vErrorChecks, ( signed portCHAR * ) "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );
xTaskCreate( vErrorChecks1, ( signed portCHAR * ) "Check1", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY1, NULL );

char * hellostr=" Hi this is mr y here, Starting Scheduler! \n ";
long* paddr=(long*)0x3ffd00c;

for(i=0;i<45;i++)
{
* paddr=hellostr;

}


vTaskStartScheduler();

return 0;
}



void vErrorChecks( void * pvParameters )
{

for (;;) {
// Task code goes here.
int i

char * hellostr="T1 \n ";
long* paddr=(long*)0x3ffd00c;

for(i=0;i<8;i++)
{
* paddr=hellostr;

}





}
}



void vErrorChecks1( void * pvParameters )
{

for (;;) {
// Task code goes here.

char * hellostr="T2 \n ";
long* paddr=(long*)0x3ffd00c;

for(i=0;i<8;i++)
{
* paddr=hellostr;

}





}
}

RE: how do I get the string to be printed once

Posted by Richard on September 3, 2008
I'm not exactly sure what the question is, but it looks like your tasks are just free running so will only get switched out each tick interrupt. They may print out the string many times between each tick. If you want it to run only once then switch to the other task add a call to taskYIELD() at the bottom of each of the two task loops.

Regards.

RE: how do I get the string to be printed once

Posted by Angel Eyes on September 3, 2008
Hi Richard ,

You are right , thats what I meant , but my problem is that any function like vTakdelay or taskYIELD if called after the loop suspends the task indefinitely . I am using the skyeye simulator for Samsung S3C4510 .

Regards


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