Asteppermotor,asitsnamesuggests,movesonestep

atatime,unlikethoseconventionalmotors,whichspin

continuously.Ifwecommandasteppermotortomove

somespecificnumberofsteps,itrotatesincrementally

thatmanynumberofstepsandstops.Becauseofthis

basicnatureofasteppermotor,itiswidelyusedinlow

cost,openlooppositioncontrolsystems.Openloop

controlmeansnofeedbackinformationabouttheposi-

tionisneeded.Thiseliminatestheneedforexpensive

sensingandfeedbackdevices,suchasopticalencod-

ers.Motorpositionisknownsimplybykeepingtrackof

thenumberofinputsteppulses.MAN822StepperMotorMicrosteppingwithPIC18C452Authors:PadmarajaYedamaleSTEPPERMOTORBASICSSandipChattopadhyayNowlet’stakeacloserlookatasteppermotor.ThefirstMicrochipTechnologyInc.thingthatwenoticeisthatithasmorethantwowiresleadingintoit.Infact,variousversionshavefour,five,INTRODUCTIONsix,andsometimesmorewires.Also,whenwemanu-