CONST
   IDREG        = 0;
   INTREG       = 2;
   CATSTAT      = 4800;
   CMSTAT       = 6002;
   VBSTAT       = 6040;
   BLANKALL     = 605C;
   OVERLAYCTL   = 60A2;
   CMINDEX      = 60B0;
   CMRED        = 60B2;
   CMGREEN      = 60B4;
   CMBLUE       = 60B6;
   PLANEMASK    = 60B8;
   CMAPWRITE    = 60F0;
   CMAPREAD     = 60F8;
   WMSTAT       = 4044;
   TCWEN1       = 4508;
   TCWEN2       = 4708;
   TCREN1       = 4504;
   TCREN2       = 4704;
   FBEN         = 4500;
   STARTMOVE    = 409C;
   RUGCMD       = 4206;
   RUGSTAT      = 4206;
   WMBLWIDTH    = 4208;
   WMBLHEIGHT   = 420A;
   WMBLSTARTX   = 4210;
   WMBLSTARTY   = 4212;
   WMBLENDX     = 4214;
   WMBLENDY     = 4216;
   WMCLIPLEFT   = 4218;
   WMCLIPRIGHT  = 421A;
   WMCLIPTOP    = 421C;
   WMCLIPBOTTOM = 421E;
   PRR          = 4502;
   WRR          = 4506;
   WMSOURCEX    = 40F2;
   WMSOURCEY    = 40F6;
   WMDESTX      = 40FA;
   WMDESTY      = 40FE;
   WMWIDTH      = 4102;
   WMHEIGHT     = 4106;
   PATTERNS     = 4400;
   TRR          = 450C;
   COLOR1       = 450E;
   COLOR2       = 470E;
   TRRCTL       = 4512;
   ACNTRL       = 4514;
   PLANEMODE    = 4516;
   
