[Dtb-talk] Some Information About the NLS Hardware DTB Players

[David B Andrews]

>From another list, the dtb-test list which is the list for NLS Pilot
Download tests.

Dave



David Andrews
Chief Technology Officer
Minnesota State Services for the Blind
2200 University Ave. W., #240
St. Paul, MN  55114-1840
(651) 642-0513  Office
(612) 730-7931  Cell
(651) 649-5927  Fax


>>> lras at loc.gov 12/28/2007 2:07 PM >>>
Hello.  Neil asked me to answer some more of the questions which
have 
arisen on this list concerning our DTB player, which is now in
field 
testing.  But he asked me last Friday, and I was already on
Christmas 
vacation (even engineers take vacations sometimes).

Some information about our hardware players can be read at
   http://www.loc.gov/nls/businessplan/playerdescription.html 
.  The links in the main part of the page are to JPG pictures, not
to 
additional descriptive material.  We haven't put a comprehensive 
description or instruction guide for the player on the web
anywhere, so 
even my additional comments will probably not answer all of your
questions.

There are two versions of the NLS player.  The DS-1 is the standard
model, 
which has controls for Play, Rewind, Fast Forward, Power, Sleep,
Volume 
up/down, Tone up/down and Speed up/down.  The DA-1, the advanced
model, has 
five additional controls:  Information, Previous item, Menu, Next
item and 
Bookmark.  There is no numeric keypad on either unit, and no
provision for 
selecting from a collection of multiple books on one cartridge or
flash 
drive.

The following describes some of the characteristics of the current

software, version 1.0.14.  There could be some minor changes in
responses 
to user feedback in the current field test, in the next round of 
large-quantity manufacturing, or after further experience. 
However, we 
believe we are close to the design goals we have set.

On both the DS-1 and DA-1 units, the Fast forward and Rewind
buttons do not 
produce chatter.  If tapped, the play position moves forward or
back in 
5-second jumps.  If held down for several seconds, these buttons
move the 
play position forward or backward by time in units of 20 seconds,
one 
minute, 5 minutes, 15 minutes, 30 minutes, 1 hour, etc.  But if
this 
movement crosses the boundary between chapters or level 1 items,
the player 
gives a beep at each chapter.  Letting up on the fast forward or
rewind 
button at that tone puts the player  on the beginning of that
section 
rather than moving the playing position by x minutes.

On the DA-1 player, the Menu key acts somewhat like a down-arrow
key on the 
players which have keypads.  You move from highest to lowest levels
in the 
book, then to pages (if available), then one-minute/phrase level,
then 
bookmark level, then back to whatever is at level 1.  Based on
markup in 
the books, we attempt to provide names for the levels in the books
or 
magazines, based on their particular structure and content.

A single NLS book must be in the root directory of the flash drive
in order 
to be recognized and played.  In addition to the Z39.86-2002 format
and 
encryption that NLS uses, the player supports unencrypted audio
Daisy 2.02 
books, and books formatted according to the Consumer Electronics 
Association structure for audio books.  It partially supports Daisy
3 audio 
books in the Z39.86-2005 format.  It can play audio files in MP3
and 
unencrypted   3GP formats, which can be arranged in folders, as
long as 
there is not a DTB in the root directory.  Even if an audio file is
in 
stereo, it will come out both headphone channels in mono.  The
players do 
not include text-to-speech, so they cannot do anything with
text-based 
DTB's or other text files.

The side USB port (hidden by a small clip-on cover) has three 
functions.  It can be used by repair personnel to do low-level 
diagnostics.  Extension controls (technically called Human
Interface 
Devices) can be connected to it.  And it is a host port, allowing
USB 
memory devices to be connected and function like a DTB cartridge. 
With the 
card readers we have tested so far, an SD card connected through
the USB 
port will only work properly while the player is running on AC 
power.  Other kinds of USB devices work without problems.

I hope this answers many of your questions.  If you have further
questions, 
please consider sending them directly to me (lras at loc.gov) or to
Neil 
(nlsdownload at loc.gov) rather than to the whole dtb-test list. 
There are 
now potentially 1,000 subscribers to this list, and the
signal-to-noise 
ratio is sometimes very poor because some of you are replying to
the whole 
list when you could reply to individuals or small groups of people.
 More 
than a dozen NLS staff read this list, but they are more likely to
take it 
seriously if it contains useful information rather than off-topic 
banter.  Having said all that, we certainly want to hear from you
and find 
this entire download project very beneficial to the program and to
its 
present and future users.

Lloyd Rasmussen, Acting Head, Engineering Section
National Library Service for the Blind and Physically Handicapped
Library of Congress    (202) 707-0535   <http://www.loc.gov/nls>
HOME:  <http://lras.home.sprynet.com>
The opinions expressed here are my own and do not necessarily
represent 
those of NLS.