EZscreen RS-232 Touchscreen Controller (V4.3)
             ===================================================


 Programming Note :
 ------------------

                     
   (A) Communication protocol is fixed as the following :

              Baud Rate = 38400 BPS
              Data Bit  = 8 Bit
              Stop Bit  = 1 Bit
              Parity    = None


   (B) Data formats : ( from touchscreen controller to PC )

       (1) TouchScreen Record :

              --------------------------------------
              Bit  #   7   6   5   4   3   2   1   0
              ------ --- --- --- --- --- --- --- ---
              Byte 1   1   0   P   0   0   0   0   0
              ------ --- --- --- --- --- --- --- ---
              Byte 2   0   0 X11 X10  X9  X8  X7  X6
              ------ --- --- --- --- --- --- --- ---
              Byte 3   0   0  X5  X4  X3  X2  X1  X0
              ------ --- --- --- --- --- --- --- ---
              Byte 4   0   0 Y11 Y10  Y9  Y8  Y7  Y6
              ------ --- --- --- --- --- --- --- ---
              Byte 5   0   0  Y5  Y4  Y3  Y2  Y1  Y0
              ---------------------------------------

               P      = Touch Status ( 0 : released, 1: pressed )
               X0-X11 = Horizontal coordiante
               Y0-Y11 = Vertical coordiantes

	       Note : The controller is equipped with a 12 bit Analog Digital
		      Converter (ADC) for providing a resolution of
		      4096x4096.

	       	      The coordinates of X and Y are the reading from
		      the ADC converter. The cursor coordinates are
		      handled by the driver with the calibration data.
		   
                      X : 0 -> 4095, Y : 0 ->4095.
		      X=0, Y=0 stands the coordinate of Left-Up corner.




       (2) Serial Mouse Record :

              --------------------------------------
              Bit  #   7   6   5   4   3   2   1   0
              ------ --- --- --- --- --- --- --- ---
              Byte 1   1   1   L   R  Y7  Y6  X7  X6
              ------ --- --- --- --- --- --- --- ---
              Byte 2   0   0  X5  X4  X3  X2  X1  X0
              ------ --- --- --- --- --- --- --- ---
              Byte 3   0   0  Y5  Y4  Y3  Y2  Y1  Y0
              --------------------------------------

               L  = Left key status ( 0 : released, 1 : pressed )
               R  = Right key status ( 0 : released, 1 : pressed )
               X  = X relative movement ( negative for moving left )
               Y  = Y relative movement ( negative for moving up )


   (C) Power Up Detection :

	      (1) Set RTS=0 (Low)
              (2) Wait at least 55 ms for controller
              (3) Set RTS=1 (High)
              (4) Read the controller ID
		  The ID should be '[TS]' ( hex : 5B, 54, 53, 5D )

    
   (D) Control Commands :

              
              (1) Set RTS=0 (Low)
              (2) Wait at least 55 ms for controller
              (3) Send the command byte listed in the following
              (4) Read the response byte from the controller
              ... Repeat step 3 and 4 for more commands
              (5) Set RTS=1 (High)


 	Function      Command Byte    Response Byte        Remark
     --------------  --------------  ---------------  --------------------

      Read model         A1h              D4h          D4 -> TSR4COM

      Read F/W Ver.      A2h              Ver. #       e.g. 10h -> V1.0

      Illegal command    ??               EFh