Control volume from iPhone and rotary encoder

[mattgt933]

I have a rotary encoder connected to my ESP32 and when I call the change volume function I can't change the volume anymore from the device that's playing the music. How would I make it so that both device can control volume at the same time?

[pschatzmann]

There is a good reason why I am asking for version info!
https://github.com/pschatzmann/ESP32-A2DP/wiki/Reporting-Bugs

Please also provide the missing details of your current logic.

In a nutshell: either you use a wrong Arduino ESP32 version or your encoder logic is wrong!

[mattgt933]

The version I am using is 2.0.11. And here is my current code:

#include <A2DPVolumeControl.h>
#include <BluetoothA2DP.h>
#include <BluetoothA2DPCommon.h>
#include <BluetoothA2DPSink.h>
#include <BluetoothA2DPSinkQueued.h>
#include <BluetoothA2DPSource.h>
#include <SoundData.h>
#include <config.h>

#include <Adafruit_NeoPixel.h>

#define PIN 4

Adafruit_NeoPixel strip = Adafruit_NeoPixel(32, PIN, NEO_GRB + NEO_KHZ800);
bool connected = true;
BluetoothA2DPSink a2dp_sink;

const int VOL_A = 5;
const int VOL_B = 7;


volatile int vol_counter = 35;
int i = 0;
void setup() {
  Serial.begin(115200); 
  i2s_pin_config_t my_pin_config = {
    .bck_io_num = 27,
    .ws_io_num = 26,
    .data_out_num = 25,
    .data_in_num = I2S_PIN_NO_CHANGE
  };
  a2dp_sink.set_pin_config(my_pin_config);
  a2dp_sink.set_auto_reconnect(true);
  a2dp_sink.start("MyMusic");
  // put your setup code here, to run once:
#if defined(__AVR_ATtiny85__)
  if (F_CPU == 16000000) clock_prescale_set(clock_div_1);
#endif
  // End of trinket special code
  strip.begin();
  strip.setBrightness(50);
  strip.show();  // Initialize all pixels to 'off'
  pinMode(VOL_A, INPUT_PULLUP);
  pinMode(VOL_B, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(VOL_A), read_encoder_vol, CHANGE);
  attachInterrupt(digitalPinToInterrupt(VOL_B), read_encoder_vol, CHANGE);

  startup();
}

void startup() {

  while (i < 8) {
    if (i == 0) { } else {
      delay(100);
      strip.setPixelColor(i, 255, 35, 0);
      strip.setPixelColor(i + 8, 255, 35, 0);
      strip.setPixelColor(i + 16, 255, 35, 0);
      strip.setPixelColor(i + 24, 255, 35, 0);
      strip.show();
    }
    i++;
  }
  delay(250);
  while (i > -1) {
    if (i == 0) { } else {
      strip.setPixelColor(i, 0, 0, 0);
      strip.setPixelColor(i + 8, 0, 0, 0);
      strip.setPixelColor(i + 16, 0, 0, 0);
      strip.setPixelColor(i + 24, 0, 0, 0);
      strip.show();
      delay(100);
    }
    i--;
  }
}

void loop() {

  static int lastVolCounter = 0;

  
  if (vol_counter != lastVolCounter) {
    lastVolCounter = vol_counter;
  }

  if (lastVolCounter <= 100 && lastVolCounter >= 0) {
    uint32_t c = strip.Color(255, 35, 0);
    uint32_t b = strip.Color(0, 0, 0);
    strip.fill(b, 25, 32);
    strip.fill(c, 25, (int)lastVolCounter / 12);
    strip.show();
    a2dp_sink.set_volume(lastVolCounter);
  }
}

void read_encoder_vol() {
  // Encoder interrupt routine for both pins. Updates counter
  // if they are valid and have rotated a full indent

  static uint8_t old_AB = 3;                                                                  // Lookup table index
  static int8_t encval = 0;                                                                   // Encoder value
  static const int8_t enc_states[] = { 0, -1, 1, 0, 1, 0, 0, -1, -1, 0, 0, 1, 0, 1, -1, 0 };  // Lookup table

  old_AB <<= 2;  // Remember previous state

  if (digitalRead(VOL_A)) old_AB |= 0x02;  // Add current state of pin A
  if (digitalRead(VOL_B)) old_AB |= 0x01;  // Add current state of pin B

  encval += enc_states[(old_AB & 0x0f)];

  // Update counter if encoder has rotated a full indent, that is at least 4 steps
  if (encval > 3) {  // Four steps forward
    int changevalue = 1;
    vol_counter = vol_counter + changevalue;  // Update counter
    encval = 0;
  } else if (encval < -3) {  // Four steps backward
    int changevalue = -1;
    vol_counter = vol_counter + changevalue;  // Update counter
    encval = 0;
  }
}

[pschatzmann]

So it's your logic then:
Don't use your own volume state but rely on the actual volume provided by the API.
Apply changes (provided by the rotary encoder) to it!

[mattgt933]

I don't think I understand what you mean...

[mattgt933]

Do you have an example of this in the repository? Thanks so much for your help!

[pschatzmann]

No, I dont have any examples. But the logic seems quite obvious to me. E.g To increment the volume you would call set_volume(get_volume()+inc); or to decrement set_volume(get_volume()-inc);

[mattgt933]

Ohhhh, now I get what you mean! Thanks so much for the help!