byte message[] = {0x81, 0x00, 0x22, 0x20, 0x28, 0x84};

void setup() {
  Serial.begin(9600);            // to the laptop
  Serial1.begin(250000);     // to the EVM board   
}

void loop() {
 
  Serial1.write(message,sizeof(message));        // send message to  EVM board
       while(Serial1.available() > 0){                            // if there's a response from the EVM board.....
       Serial.print(Serial1.read());                                // ......display it on the arduino serial monitor
    }
  delay(5000);
}