Wiimote/Extension Controllers/Drawsome Tablet

The Drawsome Tablet is identified by the 24-bit constant 0xFF00 A420 0013 (0xFFFB encrypted) at register address 0xa400fa. Some simple paint-by-numbers programs are included on a standard Wii format disc in the box with the tablet. It appears to be a collaboration between Ubisoft and Thrustmaster. The THQ uDraw is likely based on similar hardware but an incompatible data format.

Data Format

Based on the work by Matthew Watts @ https://github.com/mwvent/wii_udraw2arduino2linux

The following appears to be the data format:

Byte\Bit 7	6	5	4	3	2	1	0
0	 <-----------X-Coordinates, lower 8 bits---------------->
1	 <-----------Y-Coordinates, lower 8 bits---------------->
2	 (Y Coordinates upper 4 bits)(X Coordinates upper 4 bits)
3	 <-------------------Tip pressure 8 bits---------------->
4	 <----------------------Unknown (FF)-------------------->
5	 1	1	1	1	1     tip=1 Btn1=0 Btn2=0


The tablet is based on a Hanvon HV0818 Graphic Tablet control IC and an unknown MCU (?) for interfacing the Hanvon UART to the WiiMote. Opening the the case reveals easy to access I2C and UART pins along the edge of the board.

From Hanvon's USB tablets which this appears to be a sibling of, we can guess at the following:

  • 1024 Pressure Levels
  • 4000 Lines per Inch resolution
  • X/Y Tilt
  • Battery-free Wireless pen