The settimecode command enables or disables timecode recording for a VCR. VCR devices recognize this command.
wsprintf(lpstrCommand, "settimecode %s %s %s", lpszDeviceID,
    lpszTimecode, lpszFlags); 
 | record on | Sets the VCR to record timecode. | 
| record off | Disables timecode recording. | 
Returns zero if successful or an error otherwise.
  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
MCI Overview, MCI Command Strings