NLS: That All May Read

Materials Development Division:
Utility Software for Network Libraries

The Materials Development Division has developed software to support the deployment of the Digital Talking Book system.

This software is for the use of Network Libraries supporting the NLS program. It is also made available to NLS contractors and any other non-profit or commercial entity who wishes to build equipment for sale to libraries.

It is provided as free open source software under the terms of the license printed below.

Use of this software or of the algorithms embodied in the software by NLS contractors does not in any way alter the responsibility of the contractor to adhere to NLS specifications relevant to the contract.

Digital Talking-Book Cartridge Write Protect


Digital Talking-Book Cartridges (DTBC) manufactured for the Library of Congress NLS/BPH program conform to the standards defined by the USB Implementers Forum Link out for USB Mass Storage Devices. These drives implement the SCSI disk protocol for communication with computers (and the Digital Talking-Book player). The SCSI disk commands and data are carried over the USB transport layer.

To protect DTBCs from accidental or malicious alteration and to reduce the likelihood of theft, the NLS Engineering Section devised a method of write protecting the cartridges, implemented through additional 'vendor specific' SCSI commands.

All DTB cartridges supplied by NLS as completed DTBs will be write protected and can only be rewritten by NLS.

Cartridges sold to Network Libraries by the contract manufacturer (Northstar Systems), or from distributors, will not be supplied with the protection enabled.

Write protection of these cartridges may be applied by the Network Library during or subsequent to duplication. NLS recommends that Network Libraries apply write protection to cartridges prior to distribution.

Cartridge write protection is a separate and distinct process to book protection (DRM).
Cartridge protection
prevents alteration or erasure of the DTB files whereas book protection prevents the book being played on unauthorized devices.

The DTBC Write Protect program

The software described on this page can be used to protect cartridges purchased by Network libraries. It it supplied as an installer package for computers using the Microsoft Windows operating system. It has been tested on Windows XP and Windows 7. It has not been tested on Windows Vista.

DTBC Write Protect :

  1. Will write enable a protected drive (if supplied the correct passphrase)
  2. Will write protect DTB cartridges (if the cartridges were write enabled)
  3. Operates transparently in the background. Once running, the cartridge is write enabled upon connection and write protected on removal automatically without user intervention.

Note: The enable and protect passphrases must be re-entered of upgrading from an earlier release.

Download Code


  1. Download the installer package above.
  2. Execute the installer by double clicking the file in "windows explorer".
  3. Follow the instructions.


A desktop icon will be created called "DTBC protect". Double click this icon to launch the program. Before connecting a cartridge, use the "Configure" button to enter the passphrase that your library will use to protect cartridges. (Do not forget this passphrase. There is no way to recover a cartridge protected by a passphrase that has been forgotten or mistyped.)

The installation and operation of the program is shown in the Flash presentation below.


The DTBC write protect program will operate transparently each time a DTB flash cartridge is connected to the computer. It can be configured to:

  1. Apply a write protection passcode to a USB flash cartridge. Protecting the cartridge will prevent the accidental or malicious altering of the files contained on the cartridge.
  2. Change the write protection passcode.
  3. Clear the write protect passcode. This will permit the cartridge to be written to, or the files contained on the cartridge to be erased, on any computer without requiring this program or knowledge of the passcode.

If the USB flash cartridge write protected, the program will attempt to use the “Enable” passphrase to write enable the cartridge upon connection. If the configured passphrase is correct, the cartridge is write enabled, indicated by a green check mark on the display. If the enable passphrase does not match the passphrase that was used to protect the cartridge, the cartridge remains write protected, indicated by a red on the display.

NLSBPH DTBC Write Enable display

The operation of the program is changed by setting various parameters on the configure dialog screen. From the main page press the “Configure” button.

Configure screen

The controls on the configuration screen are:

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Posted on 2014-12-02