how to set font size for bluetooth printing?

Question

I am writing an application which print ticket receipts.
I have some how written the code to print the receipt but the printer either      

prints in very large size fonts or in very small size( not readable) fonts. Can any body provide me the code to set format.

     try {
            //////////this code runs in thread
                    OutputStream os = mBluetoothSocket
                            .getOutputStream();
                    String BILL = "";
                    BILL = BILL
                            + "     *********      ";
                    BILL = BILL+"\n***Invoice No*** \n" +
                            "Muslim Movers\n"
                            +Todays_date+"\n";

                    BILL = BILL + "\n\n";
                    BILL = BILL + "Tickets:" + "      " + String.valueOf(tickets_wanted)+"\n";
                    BILL = BILL + "Price:        "+String.valueOf(Total_Tickets)+"\n"+
                            Selectedroute+"\n";
                    BILL = BILL
                            + "     *********     \n";
                    ////textsize and allignment
                    byte[] format = { 27, 33, 0 };
                    byte[] arrayOfByte1 = { 27, 3, 0 };
                    format[2] = ((byte)(0x10 | arrayOfByte1[2]));
                    format[2] = ((byte) (0x8 | arrayOfByte1[2]));
} catch (Exception e) {
                    Log.e("Main", "Exe ", e);
}
t.start();

Answer 1

Before writing change your printer configuration:

  byte[] cc = new byte[]{0x1B,0x21,0x00};  // 0- normal size text
  byte[] bb = new byte[]{0x1B,0x21,0x08};  // 1- only bold text
  byte[] bb2 = new byte[]{0x1B,0x21,0x20}; // 2- bold with medium text
  byte[] bb3 = new byte[]{0x1B,0x21,0x10}; // 3- bold with large text

  outputStream.write(cc);
  outputStream.write("Your String");