[AT] Expects: AH 16H DL diskette drive number: 00H thru 03H ────────────────────────────────────────────────────────────────── Returns: AH 00H = diskette change line not active 01H = invalid drive number 06H = either change line is not supported or disk change line is active (media was swapped) 80H = diskette drive not ready or not installed else= BIOS disk error code if CF is set to CY ────────────────────────────────────────────────────────────────── Info: This determines whether the door of a drive has been opened since the last time the change-line was cleared (it is cleared by all successful disk accesses). When change-line is active, it does not necessarily mean a new diskette is in place -- only that the drive door has been opened at some point. Notes: ■ Use INT 13H 15H to see if a drive supports change-line detection. See Also: INT 13H: BIOS Disk I/O BIOS Data Area ROM-BIOS Functions -♦-