Different data showing in arduino serial and hyperterminal

Question

I've connected to RS232 device with arduino. When showing data in arduino its showing as:

235
157
191
157
159
153
157
0

While in Hyperterminal it's showing as:

 101 102 103 104

How to get the same data as hyperterminal in arduino too?

My Arduino code:

   if (RS232.available()) {
    int incomingByte = RS232.read();

    Serial.println(incomingByte);

    //Sending to bluetooth
    BTserial.println(incomingByte);
  }