PROGRAMMING  STEPS OF THE COUNTER AND TIMER OF THE 8051 MICRO CONTROLLER :

1. Load the TMOD register indicating which timer is used and which MOD is to be selected.

2.               Load TL & TH with initial count values.

3.               Start the timer.

4.               Keep monitoring the TF flag come out of the loop when TF = 1.

5.               Stop the timer.

6.               Clear the TF flag to continue the next counting.

7.               Again reload TH & TL.

EXAMPLE PROGRAM:

         MOV TMOD,#o1H

BACK: MOV TL0,#F2

          MOV TH0,#FFH

    CPL P1.0

    LCALL DELAY

   SJMP BACK

DELAY: SETB TR0

AGAIN: JNB TF0,AGAIN

CLR TRO

CLR TFO

RET