format  void SCL_SetShadowBit (Uint32 enable);
 Input  enable: Specify the screen to display the shadow. Multiple items can be specified simultaneously by OR operation.
  SCL_NBG0 | SCL_NBG1 | SCL_NBG2 | SCL_NBG3 |
 S  SCL_RBG0 | SCL_RBG1 | SCL_BACK | SCL_EXBG | SCL_NON
 Output  None
 Function value  None
 Function  Sets the shadow bit.
 Remarks  A shadow sprite must be prepared in advance on the VDP1 side. 

  format  voidSCL_SetFrameInterval (Uint16 count)
 Input  count: V blank interval count
 Output  None
 Function value  None
 Function  Sets the number of frame change intervals.
  Depending on the number of intervals, it has the following meaning
  0 = Frame change is in auto change mode and the number of intervals is 1.
  Synchronization with SCL_DisplayFrame () is not possible.
 1  1 ​​= Frame change is set to auto change mode and the number of intervals is 1.
  Synchronization with SCL_DisplayFrame () is possible.
  0xffff = Undefined interval manual change mode. Check the end of VDP1 drawing and
  We will change the frame.
  0xfffe = Indefinite interval manual change mode with V blank erase. VDP1
 Frame change without confirming the end of drawing .
  Other = Constant interval manual change mode with specified number of intervals.
  b15 = 0: Erase light is performed.
  = 1: Erase light will not be performed. 

  format  voidSCL_DisplayFrame (void)
 Input  None
 Output  None
 Function value  None
 Function  Turn on the frame display request flag and splice by V-BLANK interrupt routine
Wait for the display of  and  frames to complete.