RS  RW
Address  -  A2  A1  A0   --  Function
-------------------------------------
 02000H      0   0   0       Write Command Register
 02001H      0   0   1         (same as above)
 02002H      0   1   0       Read Status Register
 02003H      0   1   1         (same as above)
 02004H      1   0   0       Write Data Register
 02005H      1   0   1         (same as above)
 02006H      1   1   0       Read Data Register
 02007H      1   1   1         (same as above)