Format  Sint32 CDC_CdScan (Sint32 scandir)
 Input  scandir: Scan direction
 Output  None
 Function value  Returns an error code.
 Function  Plays back a CD.
 Scanning  Scanning continues until a CD drive command (CD playback, seek, etc.) is issued. Out of playback range
When   is reached, the scan is canceled and paused. The pose position at that time is undefined. 

(1) Scan direction

constant name	description
CDC_SCAN_FWD	Fast-forward playback (forward scan)
CDC_SCAN_RVS	Rewind playback (reverse scan)

  (2) Audio output 
When scanning and playing from the 〈PLAY〉 state, -12dB sound is output in the CD-DA area.
When scanning and playing in the CD-ROM area or 〈PAUSE〉 state, the sound is muted. 

Remarks When the CD-ROM area is scanned and played, sector data is not read. : If you try to reverse the scan direction near the boundary of the playback range, you may get out of the playback range. When reversing, pay attention to the vicinity of the boundary (within 3 to 6 seconds).