a50_knob.ino

/*******************************************************************************
#                                                                              #
#     An alternative firmware for Xiaomi Desk Lamp (Yeelight)                  #
#                                                                              #
#                                                                              #
#      Copyright (C) 2018 Tom Stöveken                                         #
#                                                                              #
# This program 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; version 2 of the License.                      #
#                                                                              #
# This program 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 this program; if not, write to the Free Software                  #
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA    #
#                                                                              #
********************************************************************************/

/* circumvent bug: https://github.com/PaulStoffregen/Encoder/issues/40 */
#define ENCODER_DO_NOT_USE_INTERRUPTS
#include <Encoder.h>
#include <OneButton.h>

#define ENCODER_A_PIN 12
#define ENCODER_B_PIN 13
#define ENCODER_SWITCH_PIN 2
#define RESET_BUTTON_PIN 14

Encoder knob(ENCODER_A_PIN, ENCODER_B_PIN);
OneButton button(ENCODER_SWITCH_PIN, true);
OneButton resetSwitch(RESET_BUTTON_PIN, true);

// remember the last time user double clicked onto knob
static unsigned long LastDoubleClick = 0;

/******************************************************************************
Description.: prepare the rotary knob encoder and switch
Input Value.: -
Return Value: -
******************************************************************************/
void setup_knob() {
  knob.write(0);

  button.attachClick([](){
    Log("Single Click!");

    // change state of desk lamp
    if( state == CONSTANTCOLOR ) {
      state = LIGHTSOFF;
    } else if( state == LIGHTSOFF ) {
      state = CONSTANTCOLOR;

      // come up with a bit of light if dimmed very low
      if ( g_brightness <= 0.01 ) {
        g_brightness = 0.02;
      }
    }
  });
  
  button.attachDoubleClick([](){
    Log("Double Click!");

    // double click twice within 2 seconds toggles WiFi
    if( millis()-LastDoubleClick <= 2000 ) {
      Log("doubleclicked knob-button twice, this toggles WiFi on/off");
      configuration.disable_WiFi = !configuration.disable_WiFi;
      writeConfig();
      delay(200);
      Log("restart now");
      ESP.restart();
    }
    
    LastDoubleClick = millis();
  });

  resetSwitch.attachLongPressStart([](){
    Log("Reset button was pressed long, resetting configuration");
    state = RESET_CONFIGURATION;
  });

  resetSwitch.attachDoubleClick([](){
    Log("Reset button was pressed twice, this toggles WiFi on/off");
    configuration.disable_WiFi = !configuration.disable_WiFi;
    writeConfig();
    delay(200);
    Log("restart now");
    ESP.restart();
  });
}

/******************************************************************************
Description.: read the rotary knob, change values if required
Input Value.: -
Return Value: -
******************************************************************************/
void loop_knob() {
  long knob_delta = knob.read();
  knob.write(0);
  
  button.tick();
  resetSwitch.tick();

  if(knob_delta == 0)
    return;

  Log("Knob changed by: " + String(knob_delta) + ".");

  switch(state) {
    case CONSTANTCOLOR:
      // if Button is held down change color otherwise change brightness
      if( !digitalRead(ENCODER_SWITCH_PIN) ) {
        g_ratio = constrain(g_ratio + 0.01*knob_delta, 0.0, 1.0);
        Log("ratio changed to: " + String(g_ratio) + ".");
      } else {
        g_brightness = constrain(g_brightness + 0.01*knob_delta, 0.0, 1.0);
        Log("brightness changed to: " + String(g_brightness) + ".");
      }
      break;

    case LIGHTSOFF:
      // knob turning ignored when light is off
      break;

    default:
      ;
  }
}