Program Listing for File servo.cpp

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/*
 * Copyright (c) 2020-2021 Advanced Robotics at the University of Washington <robomstr@uw.edu>
 *
 * This file is part of Taproot.
 *
 * Taproot is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Taproot is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Taproot.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "servo.hpp"

#include "tap/algorithms/math_user_utils.hpp"
#include "tap/architecture/clock.hpp"
#include "tap/drivers.hpp"
#include "tap/errors/create_errors.hpp"

namespace tap
{
namespace motor
{
Servo::Servo(
    Drivers *drivers,
    tap::gpio::Pwm::Pin pwmPin,
    float maximumPwm,
    float minimumPwm,
    float pwmRampSpeed)
    : drivers(drivers),
      pwmOutputRamp(0.0f),
      maxPwm(tap::algorithms::limitVal<float>(maximumPwm, 0.0f, 1.0f)),
      minPwm(tap::algorithms::limitVal<float>(minimumPwm, 0.0f, 1.0f)),
      pwmRampSpeed(pwmRampSpeed),
      prevTime(0),
      servoPin(pwmPin)
{
    if (maxPwm < minPwm)
    {
        minPwm = 0.0f;
        maxPwm = 1.0f;
        RAISE_ERROR(drivers, "min servo PWM > max servo PWM");
    }
}

void Servo::setTargetPwm(float pwm)
{
    pwmOutputRamp.setTarget(tap::algorithms::limitVal<float>(pwm, minPwm, maxPwm));
    prevTime = tap::arch::clock::getTimeMilliseconds();
}

void Servo::updateSendPwmRamp()
{
    uint32_t currTime = tap::arch::clock::getTimeMilliseconds();
    pwmOutputRamp.update(pwmRampSpeed * (currTime - prevTime));
    prevTime = currTime;
    currentPwm = pwmOutputRamp.getValue();
    drivers->pwm.write(pwmOutputRamp.getValue(), servoPin);
}

float Servo::getPWM() const { return currentPwm; }

float Servo::getMinPWM() const { return minPwm; }

float Servo::getMaxPWM() const { return maxPwm; }

bool Servo::isRampTargetMet() const { return pwmOutputRamp.isTargetReached(); }

}  // namespace motor

}  // namespace tap