format  void SCL_Open (Uint32 sclnum)
 Input  sclnum: Scroll surface number or rotation parameter table
  Normal scroll 4 (SCL_NBG0, SCL_NBG1,
 S  SCL_NBG2, SCL_NBG3) or rotation parameter table A, B
 Select from  (SCL_RBG_TB_A, SCL_RBG_TB_B)
 Output  None
 Function value  None
 Function  Makes the following functions available for the selected scroll plane.
 S  SCL_SetLineParam SCL_Move SCL_MoveTo
 S  SCL_Scale SCL_Rotate SCL_RotateTo 

  format  void SCL_Close (void)
 Input  None
 Output  None
 Function value  None
 Function  Cancels the function available state to the surface selected with SclOpen (). 

  format  void SCL_InitLineParamTb (SclLineParam * lp)
 Input  lp: Line & vertical scroll parameter data
 Output  None
 Function value  None
 Function  Initializes the line & cell scroll parameter table.