I'm trying to send data from an Arduino to an Android device.

I saw an online guide for that which provided this code:

void setup() 
{ 
  Serial.begin(115200);
} 

void loop() 
{ 
  byte msg[64]; 
  int len = Serial.available();
  if (len > 0)
  {
    len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte*
    Serial.write(msg, len);
  }
}  

I tried that example and it is working perfectly!

But when I put Serial.write("3"); in the setup loop after Serial.begin(115200); it appears as question mark on my Android device, I guess that I'm not sending it as a byte, I searched online but without any luck.

I'm trying to send data from an Arduino to an Android device.

I saw an online guide for that which provided this code:

void setup() 
{ 
  Serial.begin(115200);
} 

void loop() 
{ 
  byte msg[64]; 
  int len = Serial.available();
  if (len > 0)
  {
    len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte*
    Serial.write(msg, len);
  }
}  

I tried that example and it is working perfectly!

But when I put Serial.write("3"); in the setup loop after Serial.begin(115200); it appears as question mark on my Android device, I guess that I'm not sending it as a byte, I searched online but without any luck.

I'm trying to receive data from Arduino to Android device

i saw an online guide for that he provided this code

  void setup() 
{ 
  Serial.begin(115200);
} 

void loop() 
{ 
  byte msg[64]; 
  int len;
  len = Serial.available();
  if (len > 0)
  {
    len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte*
    Serial.write(msg, len);
  }
}  

i tried that example and it is working perfectly!

but when i put Serial.write("3"); in the setup loop after  Serial.begin(115200); it appears as question mark on my android device, i guess that I'm not sending it as a byte  , i searched online but with not luck

any ideas ?

I'm trying to send data from an Arduino to an Android device.

I saw an online guide for that which provided this code:

void setup() 
{ 
  Serial.begin(115200);
} 

void loop() 
{ 
  byte msg[64]; 
  int len = Serial.available();
  if (len > 0)
  {
    len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte*
    Serial.write(msg, len);
  }
}  

I tried that example and it is working perfectly!

But when I put Serial.write("3"); in the setup loop after Serial.begin(115200); it appears as question mark on my Android device, I guess that I'm not sending it as a byte, I searched online but without any luck.

I'am trying to recive data from arduino to Android device

i saw an online guide for that he provided this code

void setup() 

{ Serial.begin(115200); }

void loop() { byte msg[64]; int len; len = Serial.available(); if (len > 0) { len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte* Serial.write(msg, len); } } i tried that example and it is working perfectly!

i when i put Serial.write("3"); in the setup loop after Serial.begin(115200); it appears as question mark on my android device i guess that i'm not sending it as a byte i searched online but with not luck

any ideas ?

I'm trying to receive data from Arduino to Android device

i saw an online guide for that he provided this code

  void setup() 
{ 
  Serial.begin(115200);
} 

void loop() 
{ 
  byte msg[64]; 
  int len;
  len = Serial.available();
  if (len > 0)
  {
    len = Serial.readBytes((char*)msg, sizeof(msg)); // readBytes seems to need a char* not a byte*
    Serial.write(msg, len);
  }
}  

i tried that example and it is working perfectly!

but when i put Serial.write("3"); in the setup loop after Serial.begin(115200); it appears as question mark on my android device, i guess that I'm not sending it as a byte , i searched online but with not luck

any ideas ?