Timer Delay: CMSIS-RTOS RTX

Hello,

I have a problem with CMSIS-RTOS RTX.

My program works through the main()-function and after that it jumps to the Timer_Callback()-function. I didn't understand why I must define a timerDelay?

I thouhgt, that if I define a timerDelay for example 10.000 milliseconds, my program jumps every 10 seconds into the Timer_Callback()-Function, but it isn't so, it jumps every second into the Timer_Callback()-function.

I hope I could explain my problem and anyone can help me and I apologize in advance for my bad english.

Here is my source-code:

#include "LPC43xx.h"
#include "Board_GLCD.h"
#include "GLCD_Config.h"
#include "cmsis_os.h"
#include <stdio.h>

#define STRINGBUF_LEN 21
extern GLCD_FONT GLCD_Font_16x24;
char StringBuf[STRINGBUF_LEN];

void Timer_Callback(void const *arg);
osTimerDef(Timer, Timer_Callback);
uint32_t exec;

volatile int i = 0;

void Timer_Callback(void const *arg) {

        sprintf(StringBuf, "Access: %d", i);
        GLCD_DrawString(0, i*24, (char*)StringBuf);

        i++;
}


int main(void)
{
        osTimerId id;
        osStatus status;
        uint32_t timerDelay;

        GLCD_Initialize();

        GLCD_SetFont            (&GLCD_Font_16x24);
        GLCD_DrawString         (0, 0*24, "                    ");
        GLCD_DrawString         (0, 1*24, "                    ");
        GLCD_DrawString         (0, 2*24, "                    ");
        GLCD_DrawString         (0, 3*24, "                    ");
        GLCD_DrawString         (0, 4*24, "                    ");
        GLCD_DrawString         (0, 5*24, "                    ");
        GLCD_DrawString         (0, 6*24, "                    ");
        GLCD_DrawString         (0, 7*24, "                    ");
        GLCD_DrawString         (0, 8*24, "                    ");
        GLCD_DrawString         (0, 9*24, "                    ");

        exec = 2;

        id = osTimerCreate(osTimer(Timer), osTimerPeriodic, &exec);

        if(id != NULL) {
                timerDelay = 10000; // ???????????????????????????????????????????
                status = osTimerStart(id, timerDelay);

                if(status != osOK)
                        GLCD_DrawString(0, 8*24, "Timer: not started");
                else
                        GLCD_DrawString(0, 9*24, "Timer: started");
        }
}