/*----------------------------------------------------------------------------*/ /* 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. */ /*----------------------------------------------------------------------------*/ #include "PWM.h" //#include "NetworkCommunication/UsageReporting.h" #include "Resource.h" #include "Utility.h" #include "WPIErrors.h" #include "HAL/HAL.hpp" #include constexpr float PWM::kDefaultPwmPeriod; constexpr float PWM::kDefaultPwmCenter; const int32_t PWM::kDefaultPwmStepsDown; const int32_t PWM::kPwmDisabled; /** * Allocate a PWM given a channel number. * * Checks channel value range and allocates the appropriate channel. * The allocation is only done to help users ensure that they don't double * assign channels. * @param channel The PWM channel number. 0-9 are on-board, 10-19 are on the MXP * port */ PWM::PWM(uint32_t channel) { std::stringstream buf; if (!CheckPWMChannel(channel)) { buf << "PWM Channel " << channel; wpi_setWPIErrorWithContext(ChannelIndexOutOfRange, buf.str()); return; } int32_t status = 0; allocatePWMChannel(m_pwm_ports[channel], &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); m_channel = channel; setPWM(m_pwm_ports[m_channel], kPwmDisabled, &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); m_eliminateDeadband = false; HALReport(HALUsageReporting::kResourceType_PWM, channel); } /** * Free the PWM channel. * * Free the resource associated with the PWM channel and set the value to 0. */ PWM::~PWM() { int32_t status = 0; setPWM(m_pwm_ports[m_channel], kPwmDisabled, &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); freePWMChannel(m_pwm_ports[m_channel], &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); } /** * Optionally eliminate the deadband from a speed controller. * @param eliminateDeadband If true, set the motor curve on the Jaguar to * eliminate * the deadband in the middle of the range. Otherwise, keep the full range * without * modifying any values. */ void PWM::EnableDeadbandElimination(bool eliminateDeadband) { if (StatusIsFatal()) return; m_eliminateDeadband = eliminateDeadband; } /** * Set the bounds on the PWM values. * This sets the bounds on the PWM values for a particular each type of * controller. The values * determine the upper and lower speeds as well as the deadband bracket. * @param max The Minimum pwm value * @param deadbandMax The high end of the deadband range * @param center The center speed (off) * @param deadbandMin The low end of the deadband range * @param min The minimum pwm value */ void PWM::SetBounds(int32_t max, int32_t deadbandMax, int32_t center, int32_t deadbandMin, int32_t min) { if (StatusIsFatal()) return; m_maxPwm = max; m_deadbandMaxPwm = deadbandMax; m_centerPwm = center; m_deadbandMinPwm = deadbandMin; m_minPwm = min; } /** * Set the bounds on the PWM pulse widths. * This sets the bounds on the PWM values for a particular type of controller. * The values * determine the upper and lower speeds as well as the deadband bracket. * @param max The max PWM pulse width in ms * @param deadbandMax The high end of the deadband range pulse width in ms * @param center The center (off) pulse width in ms * @param deadbandMin The low end of the deadband pulse width in ms * @param min The minimum pulse width in ms */ void PWM::SetBounds(double max, double deadbandMax, double center, double deadbandMin, double min) { // calculate the loop time in milliseconds int32_t status = 0; double loopTime = getLoopTiming(&status) / (kSystemClockTicksPerMicrosecond * 1e3); wpi_setErrorWithContext(status, getHALErrorMessage(status)); if (StatusIsFatal()) return; m_maxPwm = (int32_t)((max - kDefaultPwmCenter) / loopTime + kDefaultPwmStepsDown - 1); m_deadbandMaxPwm = (int32_t)((deadbandMax - kDefaultPwmCenter) / loopTime + kDefaultPwmStepsDown - 1); m_centerPwm = (int32_t)((center - kDefaultPwmCenter) / loopTime + kDefaultPwmStepsDown - 1); m_deadbandMinPwm = (int32_t)((deadbandMin - kDefaultPwmCenter) / loopTime + kDefaultPwmStepsDown - 1); m_minPwm = (int32_t)((min - kDefaultPwmCenter) / loopTime + kDefaultPwmStepsDown - 1); } /** * Set the PWM value based on a position. * * This is intended to be used by servos. * * @pre SetMaxPositivePwm() called. * @pre SetMinNegativePwm() called. * * @param pos The position to set the servo between 0.0 and 1.0. */ void PWM::SetPosition(float pos) { if (StatusIsFatal()) return; if (pos < 0.0) { pos = 0.0; } else if (pos > 1.0) { pos = 1.0; } // note, need to perform the multiplication below as floating point before // converting to int unsigned short rawValue = (int32_t)((pos * (float)GetFullRangeScaleFactor()) + GetMinNegativePwm()); // printf("MinNegPWM: %d FullRangeScaleFactor: %d Raw value: %5d Input //value: %4.4f\n", GetMinNegativePwm(), GetFullRangeScaleFactor(), rawValue, //pos); // wpi_assert((rawValue >= GetMinNegativePwm()) && (rawValue <= //GetMaxPositivePwm())); wpi_assert(rawValue != kPwmDisabled); // send the computed pwm value to the FPGA SetRaw((unsigned short)rawValue); } /** * Get the PWM value in terms of a position. * * This is intended to be used by servos. * * @pre SetMaxPositivePwm() called. * @pre SetMinNegativePwm() called. * * @return The position the servo is set to between 0.0 and 1.0. */ float PWM::GetPosition() const { if (StatusIsFatal()) return 0.0; int32_t value = GetRaw(); if (value < GetMinNegativePwm()) { return 0.0; } else if (value > GetMaxPositivePwm()) { return 1.0; } else { return (float)(value - GetMinNegativePwm()) / (float)GetFullRangeScaleFactor(); } } /** * Set the PWM value based on a speed. * * This is intended to be used by speed controllers. * * @pre SetMaxPositivePwm() called. * @pre SetMinPositivePwm() called. * @pre SetCenterPwm() called. * @pre SetMaxNegativePwm() called. * @pre SetMinNegativePwm() called. * * @param speed The speed to set the speed controller between -1.0 and 1.0. */ void PWM::SetSpeed(float speed) { if (StatusIsFatal()) return; // clamp speed to be in the range 1.0 >= speed >= -1.0 if (speed < -1.0) { speed = -1.0; } else if (speed > 1.0) { speed = 1.0; } // calculate the desired output pwm value by scaling the speed appropriately int32_t rawValue; if (speed == 0.0) { rawValue = GetCenterPwm(); } else if (speed > 0.0) { rawValue = (int32_t)(speed * ((float)GetPositiveScaleFactor()) + ((float)GetMinPositivePwm()) + 0.5); } else { rawValue = (int32_t)(speed * ((float)GetNegativeScaleFactor()) + ((float)GetMaxNegativePwm()) + 0.5); } // the above should result in a pwm_value in the valid range wpi_assert((rawValue >= GetMinNegativePwm()) && (rawValue <= GetMaxPositivePwm())); wpi_assert(rawValue != kPwmDisabled); // send the computed pwm value to the FPGA SetRaw(rawValue); } /** * Get the PWM value in terms of speed. * * This is intended to be used by speed controllers. * * @pre SetMaxPositivePwm() called. * @pre SetMinPositivePwm() called. * @pre SetMaxNegativePwm() called. * @pre SetMinNegativePwm() called. * * @return The most recently set speed between -1.0 and 1.0. */ float PWM::GetSpeed() const { if (StatusIsFatal()) return 0.0; int32_t value = GetRaw(); if (value == PWM::kPwmDisabled) { return 0.0; } else if (value > GetMaxPositivePwm()) { return 1.0; } else if (value < GetMinNegativePwm()) { return -1.0; } else if (value > GetMinPositivePwm()) { return (float)(value - GetMinPositivePwm()) / (float)GetPositiveScaleFactor(); } else if (value < GetMaxNegativePwm()) { return (float)(value - GetMaxNegativePwm()) / (float)GetNegativeScaleFactor(); } else { return 0.0; } } /** * Set the PWM value directly to the hardware. * * Write a raw value to a PWM channel. * * @param value Raw PWM value. */ void PWM::SetRaw(unsigned short value) { if (StatusIsFatal()) return; int32_t status = 0; setPWM(m_pwm_ports[m_channel], value, &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); } /** * Get the PWM value directly from the hardware. * * Read a raw value from a PWM channel. * * @return Raw PWM control value. */ unsigned short PWM::GetRaw() const { if (StatusIsFatal()) return 0; int32_t status = 0; unsigned short value = getPWM(m_pwm_ports[m_channel], &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); return value; } /** * Slow down the PWM signal for old devices. * * @param mult The period multiplier to apply to this channel */ void PWM::SetPeriodMultiplier(PeriodMultiplier mult) { if (StatusIsFatal()) return; int32_t status = 0; switch (mult) { case kPeriodMultiplier_4X: setPWMPeriodScale(m_pwm_ports[m_channel], 3, &status); // Squelch 3 out of 4 outputs break; case kPeriodMultiplier_2X: setPWMPeriodScale(m_pwm_ports[m_channel], 1, &status); // Squelch 1 out of 2 outputs break; case kPeriodMultiplier_1X: setPWMPeriodScale(m_pwm_ports[m_channel], 0, &status); // Don't squelch any outputs break; default: wpi_assert(false); } wpi_setErrorWithContext(status, getHALErrorMessage(status)); } void PWM::SetZeroLatch() { if (StatusIsFatal()) return; int32_t status = 0; latchPWMZero(m_pwm_ports[m_channel], &status); wpi_setErrorWithContext(status, getHALErrorMessage(status)); } void PWM::ValueChanged(std::shared_ptr source, const std::string& key, EntryValue value, bool isNew) { SetSpeed(value.f); } void PWM::UpdateTable() { if (m_table != nullptr) { m_table->PutNumber("Value", GetSpeed()); } } void PWM::StartLiveWindowMode() { SetSpeed(0); if (m_table != nullptr) { m_table->AddTableListener("Value", this, true); } } void PWM::StopLiveWindowMode() { SetSpeed(0); if (m_table != nullptr) { m_table->RemoveTableListener(this); } } std::string PWM::GetSmartDashboardType() const { return "Speed Controller"; } void PWM::InitTable(std::shared_ptr subTable) { m_table = subTable; UpdateTable(); } std::shared_ptr PWM::GetTable() const { return m_table; }