Panasonic VDR-M30PP Service Manual page 15

The VDR-M30 is equipped with a software disc-protect function instead of an erase-prevention
mechanism: The erase-prevention mechanism is not provided with new round disc holder because of
its structure.
The software disc-protect function writes the protect data to DVD-RAM disc to prevent data on it
from being accidentally erased: It performs the same function as the write-protect tab of
conventional disc cartridge, using software. Software disc-protect can repeatedly be set and released
on one disc, in the same way as the mechanical write-protect tab.
The software disc-protect function is included in the DVD-RAM disc specifications defined by DVD
Forum. Therefore, the disc-protect set on VDR-M30 can be released or set again on devices equipped
with the same function.
DVD video camera/recorders that use DVD-RAM disc packed in a cartridge are not equipped with
the software disc-protect function, since a write-protect tab is provided on the cartridge. Therefore, if
a disc for which software disc-protect has been set is put in a cartridge and the write-protect tab is
released, the disc can be played back on those DVD video camera/recorders, but no recording or
editing can be performed on them. To record or edit such discs, release the software disc-protect on
VDR-M30 or on another device equipped with the same function.