WiFlasher/wiflash_esp32/strobe_esp32.cpp

/*
  strobe_esp32.cpp

  Part of WiFlash_esp32

  Copyright (c) 2020 Kevin Matz (kevin.matz@gmail.com)

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/

#include <Arduino.h>
#include "strobe_esp32.h"

/*
   calculate period from DMX value
*/
uint32_t hz_to_micros(uint8_t dmx) {
  if (dmx == 0) {
    return 0;
  }
  // ( millis / ( percent * scalor ) + offset ) * micros
  return (1000 / (((dmx / 255.0) * 24.5) + 0.5)) * 1000;
}


/*
   calculate duration from DMX value
*/
uint32_t dr_to_micros(uint8_t dmx) {
  //      (( percent * scalor) + offset) * micros
  return (((dmx / 255.0) * .5 ) + .01 ) * 1000 * 1000;
}


/*
   Constructor
*/
Strobe::Strobe(e131_listen_t type, uint16_t universe, uint16_t address) {
  m_type = type;
  m_universe = universe;
  m_address = address;
  m_e131 = new ESPAsyncE131(1);
  m_e131->onPacket(std::bind(&Strobe::recvData, this,
                             std::placeholders::_1));
}

/*
   call durring setup()
*/
bool Strobe::begin(uint8_t pin, uint8_t pwm) {
  bool success = false;
  // set state
  m_pwm = pwm;
  m_state = STROBE_INACTIVE;
  m_level = 0;

  // configure hardware
  ledcAttachPin(pin, m_pwm);    // Attach GPIO to PWM timer
  ledcSetup(m_pwm, 2400, 15);   // 2.4KHz PWM, 15 bit resolutio
  ledcWrite(m_pwm, m_level);    // LED to 0%

  // start sACN
  if (!m_e131->begin(m_type, m_universe)) {
    Serial.println("Failed to start E1.31");
  } else {
    Serial.println("Listening for sACN");
    success = true;
  }
    
  return success;
}

void Strobe::update(void * args) {
  // stop stobing on sACN loss of signal
//  if (millis() - m_e131->stats.last_seen > 10000) {
//    Serial.println("No Signal!");
//    m_int = 0;
//  }

  // intensity changes start/stop the cycle
  if (m_int == 0) {
    // intensity off breaks the cycle
    m_state = STROBE_INACTIVE;
  } else {
    if (m_state == STROBE_INACTIVE) {
      // going active
      m_state = STROBE_ACTIVE_ON;
    }
  }

  // time based cycle changes
  if (m_state == STROBE_ACTIVE_ON ||
      m_state == STROBE_ACTIVE_OFF) {
    uint32_t now, elapsed, period, durr;
    now = micros();
    
    elapsed = now - m_time;
    period = hz_to_micros(m_rat);
    durr = dr_to_micros(m_dur);

    if (elapsed > period ||         // hz period completed
        now < m_time) {           // micros() wraps 32 bits every ~70 min.
      // cycle restarts
      m_state = STROBE_ACTIVE_ON;
      m_time = now;
    } else if (elapsed > durr) {  // durration period completed
      // cycle enters dark phase
      m_state = STROBE_ACTIVE_OFF;
    }
  }

  // set LED output
  if (m_state == STROBE_ACTIVE_ON) {
    setLevel(m_int);
  } else {
    setLevel(0);
  }
}


/*
   Write a 15bit level to PWM
*/
void Strobe::setLevel(uint16_t level) {
  if (level != m_level) {
    m_level = level;
    ledcWrite(m_pwm, ((m_level >> 1) & 0xffff)); // write at 15 bit PWM
  }
}

void Strobe::recvData(e131_packet_t *packet) {
  //Serial.println(m_e131->stats.num_packets);
  m_int = packet->property_values[m_address + 0] << 8 |
          packet->property_values[m_address + 1];
  m_dur = packet->property_values[m_address + 2];
  m_rat = packet->property_values[m_address + 3];
}