Issue ESP 32 + isolator adafruit

Hi
I started to connect one esp32 with one sensor Myoware with an isolator from Adafruit but The software could'nt reconize the esp32. Any ideas?


Thank you so much

here the code :

#include <WiFi.h>
/*WIFI*/
const char* ssid     = ";;;"; //nome de wifi(ssid)
const char* password = ";;;;"; //mod de passe
const char* ipAdress = ";;;;"; //adress ip de serveur
const uint16_t port = 5888; //port de serveur
WiFiClient client;

//code EMG to ESP32
const int pinEMG = 33;
int signalEMG = 0;
int signalsensor = 0;


void setup()
{  

    Serial.begin(115200);
    delay(10);
    /*WIFI connection*/
    Serial.println();
    Serial.println();
    Serial.print("Connecting to ");
    Serial.println(ssid);

    WiFi.begin(ssid, password);

    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }

    Serial.println("");
    Serial.println("WiFi connected.");
    Serial.println("ipAdress");
    Serial.println(WiFi.localIP());
    
    if (client.connect(ipAdress, port)) {
      Serial.println("connected");
      client.println("hello!!!!!!!");//client repond
    }
    else
    {
      Serial.println("cant find server");
    }


}

void loop(){
  // lire tout les char envoie par serveur
 {
  while (client.available()) {
    char c = client.read();
    Serial.println(c);//imprimer char
  }
 }
// lecture signal EMG
 signalEMG = analogRead(pinEMG);
   signalsensor = map(signalEMG,4096,2500,0,500);

  Serial.println(signalsensor);

    if (client.connected()) {
    client.println(String(signalsensor) + ",0");  // Envoie de la donnée sous le format attendu par Unity
  }
  delay(100);



 
 //client.println(millis());
 
 //client repond le temp actuel
 delay(10);
 
  //client.flush();
  // si le client perd la connection, arrete le client:
  if (!client.connected()) {
    Serial.println();
    Serial.println("disconnecting.");
    client.stop();

    for(;;)
      ;
  }

}

Which isolator; please post a link.
Which Myoware sensor; please post a link.

Please provide a schematic diagram showing all connections between the different components in your setup; this includes all power/gnd as well.

Which software? The IDE?
What does your operating system (which one?) think about your setup; does it recognise the ESP32?

isolator : Adafruit USB Isolator - 100mA Isolated Low/Full Speed USB : ID 2107 : Adafruit Industries, Unique & fun DIY electronics and kits
Myoware : MyoWare 2.0 Muscle Sensor
Arduino 1.8.12

Without isolator, The software can detect the signals


Hi @al64.

The corrupted line from the Serial Monitor should have said:

Brownout detector was triggered

If this is appearing while the ESP32 board is connected to your computer via the USB isolator, but does not appear while the board is directly connected, it indicates that the current the isolator is capable of supplying is less than what is required by your system.

This is not surprising as the isolator is only rated for 100 mA and even the ESP32 alone can momentarily draw more current than that when using the Wi-Fi radio.

The "brownout detector" is a system in the ESP32 microcontroller that automatically resets it if it detects that the operating voltage has dropped below the minimum level required for reliable operation. This is done because if the voltage drops below the minimum level (but not to 0 V), then the microcontroller can be left in a non-functional state even after the voltage increases to a level above the minimum. In this case, it is better to just reset to restore functionality.

ok thank you so much to confirm my thoughts. Any ideas so to change for another? thank you

Unfortunately I'm not knowledgeable in this subject of isolation so I am not able to advise on a solution other than the obvious ones of either not using the isolator (if it isn't actually required for the project), or using a different isolator that can supply more current. Hopefully the other forum helpers will be able to provide qualified advice.

You could power the system through a separate power supply. However, depending on the specifics of how the power is supplied, this could result in a loss of isolation.