0x0000 OFFSET
0xBFF0 WM_USER0
0xBFF1 WM_USER1
0xBFF2 WM_USER2
0xBFF3 WM_USER3
0xBFF4 WM_USER4
0xBFF5 WM_USER5
0xBFF6 WM_USER6
0xBFF7 WM_USER7
0xBFF8 WM_USER8
0xBFF9 WM_USER9
0xBFFA WM_USERA
0xBFFB WM_USERB
0xBFFC WM_USERC
0xBFFD WM_USERD
0xBFFE WM_USERE
0xBFFF WM_USERF
