tms320vc5505 timer

hai

           i am using the tms320vc5505 usbstick and by enabling the timer and i toggle the led for every 50ms it works fine when we run in the initial stage and after some time it automatically stops the timer and it never comes to the reset position. what area are i am getting mistake in the timer interrupt or in the main program. in the interrupt routine i disable the timer interrupt and i stop the timer and again i restarted the timer in the interrupt routine.

with regards

seeni