/*----------------------------------------------------------------------------*/ /* Copyright (c) FIRST 2008. All Rights Reserved. */ /* Open Source Software - may be modified and shared by FRC teams. The code */ /* must be accompanied by the FIRST BSD license file in $(WIND_BASE)/WPILib. */ /*----------------------------------------------------------------------------*/ #pragma once #include "SensorBase.h" #include "simulation/SimContinuousOutput.h" #include "LiveWindow/LiveWindowSendable.h" #include "tables/ITableListener.h" #include /** * Class implements the PWM generation in the FPGA. * * The values supplied as arguments for PWM outputs range from -1.0 to 1.0. They are mapped * to the hardware dependent values, in this case 0-255 for the FPGA. * Changes are immediately sent to the FPGA, and the update occurs at the next * FPGA cycle. There is no delay. * * As of revision 0.1.10 of the FPGA, the FPGA interprets the 0-255 values as follows: * - 255 = full "forward" * - 254 to 129 = linear scaling from "full forward" to "center" * - 128 = center value * - 127 to 2 = linear scaling from "center" to "full reverse" * - 1 = full "reverse" * - 0 = disabled (i.e. PWM output is held low) */ class PWM : public SensorBase, public ITableListener, public LiveWindowSendable { public: enum PeriodMultiplier { kPeriodMultiplier_1X = 1, kPeriodMultiplier_2X = 2, kPeriodMultiplier_4X = 4 }; explicit PWM(uint32_t channel); virtual ~PWM(); virtual void SetRaw(unsigned short value); void SetPeriodMultiplier(PeriodMultiplier mult); void EnableDeadbandElimination(bool eliminateDeadband); void SetBounds(int32_t max, int32_t deadbandMax, int32_t center, int32_t deadbandMin, int32_t min); void SetBounds(double max, double deadbandMax, double center, double deadbandMin, double min); uint32_t GetChannel() const { return m_channel; } protected: /** * kDefaultPwmPeriod is in ms * * - 20ms periods (50 Hz) are the "safest" setting in that this works for all devices * - 20ms periods seem to be desirable for Vex Motors * - 20ms periods are the specified period for HS-322HD servos, but work reliably down * to 10.0 ms; starting at about 8.5ms, the servo sometimes hums and get hot; * by 5.0ms the hum is nearly continuous * - 10ms periods work well for Victor 884 * - 5ms periods allows higher update rates for Luminary Micro Jaguar speed controllers. * Due to the shipping firmware on the Jaguar, we can't run the update period less * than 5.05 ms. * * kDefaultPwmPeriod is the 1x period (5.05 ms). In hardware, the period scaling is implemented as an * output squelch to get longer periods for old devices. */ static const float kDefaultPwmPeriod; /** * kDefaultPwmCenter is the PWM range center in ms */ static const float kDefaultPwmCenter; /** * kDefaultPWMStepsDown is the number of PWM steps below the centerpoint */ static const int32_t kDefaultPwmStepsDown; static const int32_t kPwmDisabled; virtual void SetPosition(float pos); virtual float GetPosition() const; virtual void SetSpeed(float speed); virtual float GetSpeed() const; bool m_eliminateDeadband; int32_t m_centerPwm; void ValueChanged(ITable* source, llvm::StringRef key, std::shared_ptr value, bool isNew) override; void UpdateTable() override; void StartLiveWindowMode() override; void StopLiveWindowMode() override; std::string GetSmartDashboardType() const override; void InitTable(std::shared_ptr subTable) override; std::shared_ptr GetTable() const override; std::shared_ptr m_table; private: uint32_t m_channel; SimContinuousOutput* impl; };