pic microcontrollers are programmable devices. you 'burn' code into their memory and they execute it, usually in an endless loop.. the advantages for this intelligent control of motors is many-fold. (and i cannot begin to explain it all)
the main advantage when driving stepping motors in either bipolar or unipolar operation would the ability to easily create multi-stepping sequences... so you 'fake' higher motor resolution. the other would be easier integration of a constant current(hence constant torque) drive.
i suppose there are other benefits also.. but these would be the main ones. the advantage of using pic-micro driver boards as opposed to the really nice and affordable xylotex boards would be the flexibiliy of output transistors(and therefor power ratings) of a DIY solution.. 15amp transistors make a 15amp drive.. twice the rating of a gecko. probably 1/4 the cost..
however, you get what you pay for. |