"timer0_overflow_count" in 8051 Microcontroller

i have been using "timer0_overflow_count" in 8051 Microcontroller what can i do in arduino ? as i have no experience in using arduino at all. any help will be appreciate .

void timer(void) interrupt 1 //interrupt from impulse

What are you trying to achieve? There may be a better way in the Arduino than overflowing a timer.

For instance, you may find the TimerOne library useful for what you are doing.