import?time


##PID?Library
class?PID（object）:
????##Constants?used?in?some?of?the?functions?below
????pid_AUTOMATIC?=?1
????pid_MANUAL?=?0
????pid_DIRECT?=?0
????pid_REVERSE?=?1

????direction?=?0

????def?__init__（self?Setpoint?Kp?Ki?Kd?ControllerDirection）:
????????self.mySetpoint?=?Setpoint
????????self.inAuto?=?0
????????self.myOutput=0
????????self.Kp?=?Kp
????????self.Ki?=?Ki
????????self.Kd?=?Kd
????????self.ControllerDirection?=?ControllerDirection
????????self.SetOutputLimits（0?255）
????????self.SampleTime?=?100
????????self.myInput=0
????????self.SetControllerDirection（self.ControllerDirection）
????????self.lastTime?=?int（round（time.time（）?*?1000））?-?self.SampleTime

????def?Compute（self）:
????????if?（self.inAuto?==?0）:
????????????return?0
????????now?=?int（round（time.time（）?*?1000））
????????timeChange?=?（now?-?self.lastTime）
????????if?（timeChange?>=?self.SampleTime）:
????????????#?/*Compute?all?the?working?error?variables*/
????????????Input?=?self.myInput
????????????error?=?self.mySetpoint?-?Input
????????????self.ITerm?+=?（self.Ki?*?error）
????????????if?（self.ITerm?>?self.outMax）:
????????????????self.ITerm?=?self.outMax
????????????elif?（self.ITerm?????????????????self.ITerm?=?self.outMin
????????????dInput?=?（Input?-?self.lastInput）

????????????#?/*Compute?PID?Output*/
????????????self.output?=?self.Kp?*?error?+?self.ITerm?-?self.Kd?*?dInput

????????????if?（self.output?>?self.outMax）:
????????????????self.output?=?self.outMax
????????????elif?（self.output?????????????????self.output?=?self.outMin
????????????self.myOutput?=?self.output

????????????????#?/*Remember?some?variables?for?next?time*/
????????????self.lastInput?=?Input
????????????self.lastTime?=?now
????????????return?1

????????else:
????????????return?0

????def?SetTunings（self?Kp?Ki?Kd）: