Setup for stepping on revolution counter

Hello to all.

I need to code a visual basic routine that would do a number of steps triggered by a sensor that counts turns. Sensor is likely to be optical.

Is there a simple setup for this?

I need it to be from VB as the number of steps is determined by a separate software.

I'd hate to do loops in VB to check the sensor signal, would rather have some sort of trigger device/code.

Thanks in advance.