david rob wrote:
-------------------------------

ok here's what i am doing.
I am using 8052 derivative micro controller.
I am driving the stepper motor by the use of the sequence 12,6,3,9.The pin 3.2 has been made an input pin for receving the reflection from the reflective tapes.once the signal is receieved i send the step data at this point to the pc.Then the no. of transitions are checked it is 2 for one target and 6 for the other target.i will have to do similar thing for the anticlockwise direction and at no point the stepper motor stop stop rotating and also it shld keep counting the no. of steps.


that's only part of the story.... It does _NOT_ explain the code you have written.

Again:

A) Organise your thoughts. Break down the problem in manageable chunks, try to develop a solution _without_ coding, ie draw a flowchart, then start coding, test it and come back with well documented code.


B) See previous post(s).

regards
Patrick