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libnjb-2.2.6-2mdv2008.1.x86_64.rpm

Nomad Jukebox API
v2.2.6
2007-09-05

http://libnjb.sourceforge.net/
http://www.sourceforge.net/projects/libnjb/


Release Notes
-------------

This is the second release of the C API for the Nomad Jukebox.
For changes regarding the API, see CHANGELOG. You should also
read the new documentation that can be generated with doxygen
(just run "doxygen" in the root directory, output in doc/html)
or found at http://libnjb.sourceforge.net/api/html/

This library has successfully been built and tested under:

   FreeBSD 5.1-RELEASE (x86)
   Linux 2.4.20 (x86)
   MacOS X (Darwin, PowerPC)
   Microsoft Windows (Win2K)
   Solaris (using Suns port of libusb)

NetBSD users may be able to build this library as well, with
minimal or no porting, due to the fact that FreeBSD uses the NetBSD
USB stack. We have not built libnjb for VMS, BeOS, OS/2 and
<insert your favourite obscure OS here>. Help us port it if you're
interested!

These devices are handled, more or less perfect:

* Creative NOMAD Jukebox 1 a.k.a. Creative D.A.P.
* Creative NOMAD Jukebox 2
* Creative NOMAD Jukebox 3
* Creative NOMAD Jukebox Zen
* Creative NOMAD Jukebox Zen USB 2.0
* Creative NOMAD Jukebox Zen NX
* Creative NOMAD Jukebox Zen Xtra
* Creative Zen Touch
* Creative Zen Micro
* Creative Zen Sleek
* Creative Zen
* Dell Digital Jukebox ("Dell DJ")
* Second Generation Dell Digital Jukebox
* Dell Pocket DJ
* Third Generation Dell Digital Jukebox

Newer devices have a 2.x MTP/PlaysForSure firmware upgrade -  we 
do not support MTP so please don't install it!

THESE DEVICES ARE NOT SUPPORTED:

Creative Zen Portable Media Center
Creative Zen MicroPhoto
Any other MTP/PlaysForSure device

If you want to use MTP devices under Linux you are currently out of
luck. Please start hacking up an MTP library if you have nothing better
to do, there is even a protocol specification for it!


NJB Issues
----------

It's pretty easy to "wedge" your JukeBox during a session.  If you get
stuck with a "Host is in control" message, simply disconnect the USB
cable and reconnect it.  Apparently, the documentation that Creative
provides warns against this activity, but USB devices are hot-pluggable,
so it won't hurt anything (the standard disclaimers apply, of course).


Issues with newer jukeboxes
---------------------------

Some users of NOMAD Jukebox Xtra have reported problems when using the
library for the first time. This seems to be caused by the playlist
of preloaded content. Try to remove all playlists by using the menus
on the device, and see if this solves your problem.


USB issues
----------

Some users experience problems with USB communication. There are some
hardware USB controllers which is problematic. This might be caused
by either electrical properties of the bus, or by badly programmed 
drivers in the host kernel.

nForce 2 motherboards are known to be problematic.


FreeBSD Performance Considerations
----------------------------------

It appears that the uhci device under some FreeBSD releases performs
poorly on bulk data transfers.  The USB 1.1 specification defines
1000 "frames" every second, for 1 frame per ms.  The host controller
determines how many packets to place in each frame, based on available
bandwidth and bandwidth requirements.  This is called "bandwidth
reclaimation", and the FreeBSD USB stack does not do this as of
4.x-RELEASE.  The end result is only one packet sent per frame,
which severely limits the transfer rate: the NJB uses 64-byte
packets, and the math gives us a data transfer rate of 64,000
bytes/second.  Yuck.

If you have a UHCI USB controller, this will bite you.  If you have
an OHCI USB controller, the ohci device driver "does the right
thing", and will give you 430kb/second (or so).  However, there is
a caveat: I have noticed some instabilities in the ohci driver, so
you may have problems here, too.

This problem with the uhci stack has been fixed under NetBSD and
FreeBSD 5.x.

Some BSD:s have a problem with USB 2.0: the EHCI driver may need a patch
(e.g. /FreeBSD-CVS/src/sys/dev/usb/ehci.c). The latest versions of 
NetBSD have the problem fixed.


Compilation of programs under MacOS X
-------------------------------------

Older versions of libusb for Darwin does not handle short USB writes
properly, which is a prerequisite for libnjb to work. This has been
fixed since the 0.1.8 version of libusb.

If you're writing your own applications to use libnjb under MacOS X
you will have to add the line "-framework IOKit" to your CFLAGS.
If you use compilation with pkg-config the flags will be added
automatically and you need not worry about it, see below on 
"compiling programs for libnjb".


Compilation of programs under Windows/Win32
-------------------------------------------

See the separate README.TXT file in the "windows" subdirectory.


What Works
----------

Most of the functions in the API have been tested and documented.
Right now, using the API, you can:

   - transfer audio tracks to and from the NJB
   - delete audio tracks
   - manage playlists (create, rename, update and delete)
   - get playlist information
   - send and recieve data files
   - get data file metadata
   - obtain disk usage (free and total bytes)
   - get an set the "owner" string
   - play tracks
   - manipulate sound parameters (volume and EAX)
   - obtain full internationalization using UTF-8 unicode


What Will Never Get Done
------------------------

There exists an API for firmware upgrading of the series 3 devices.
This API is unsupported and you shall not use it. IT HAS NEVER BEEN
TESTED. It was only implemented out of curiostity. This may 
disappoint some of you, but we don't care, because:

   1) Creative doesn't release the firmware as standalone data blocks
      for transferring.

   2) Of all the functions in the USB protocol, the firmware update 
      is the only one that could potentially render your NJB unusable.

   3) We're not willing to use our own NJBs as a guinea pigs.  If we're not
      comfortable doing this to ourselves, then we're sure as hell not 
      going to do it to other people.

Send us guinea pig NJBs and we might support it some day.  ;)

For more information see below about the firmware upgrade sample
program.


Building and Installing
-----------------------

See the "INSTALL" file.


Compiling programs for libnjb
-----------------------------

libnjb has support for the pkg-config script by adding a libnjb.pc 
entry in $(prefix)/lib/pkgconfig. To compile a libnjb program, 
just write:

gcc -o foo `pkg-config --cflags --libs libnjb` foo.c

This also simplifies compilation using autoconf and pkg-config: just 
write e.g.

PKG_CHECK_MODULES(NJB, libnjb)
AC_SUBST(NJB_CFLAGS)
AC_SUBST(NJB_LIBS)

To have libnjb LIBS and CFLAGS defined. Needless to say, this will 
only work if you have pkgconfig installed on your system, but most 
people have nowadays.

If your library is installed in e.g. /usr/local you may have to tell
this to pkgconfig by setting the PKG_CONFIG_PATH thus:

export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig


Firmware upgrade sample program
-------------------------------

As of libnjb 2.1 there is a small program that can extract firmware
from Windows executables or use previously extracted raw firmwares
and send them to the series 3 devices. This sample program is called
"fwupgrade" and lives in the "samples" directory.

* The first rule of fwupgrade is you don't use fwupgrade.

* The second rule of fwupgrade is you DON'T USE FWUPGRADE.

Extracting the firmware from Windows executables is relatively easy,
just download Creative's firmware installer .exe file and run
"fwupgrade" against it. If this fails, the executable may be
compressed. Then you have to start the executable in Windows (or
WINE or whatever) and copy the uncompressed executable from some
temporary directory under:

C:\Documents and Settings\<yourusername>\Local Settings\Temp

For example the firmware upgrade for Zen USB 2.0 version 1.11.01
is named "JBZen2PCFW_1_11_01.exe" but this is not possible to use
with "fwupgrade". You need to run that executable and then locate
a file named "Zen(USB2.0)Upgrade_1_11_01.exe" somewhere in that
temporary directory. Different Windows versions may put these
extracted files in different places. The extracted executable can
be run through fwupgrade. The Dell DJ firmwares comes in a handy
self-extracting archive (this can be run using a Windows emulator
such as WINE if desired).

Newer firmwares, such as the Zen Micro firmwares, seem to be 
uncompressed or compressed with RAR. Try to extract the contents
using a RAR un-archiver, perhaps WinRAR.

What we do is to go into a Windows executable and extract the 
firmware, which is compressed with the free software library
zlib. Newer firmware seem to not be compressed with zlib.

Needless to say, there is no guarantee about anything related to
fwupgrade. And by the way, don't use fwupgrade.


Documentation
-------------

Read the new documentation that can be generated with doxygen
(just run "doxygen" in the root directory, output in doc/html)
or found at http://libnjb.sourceforge.net/api/html/

The NJB USB Protocol Guide, available from SourceForge from the 
same place where you got libnjb, has some nice info on the lower
level protocol on the NJB1. For other models, see the file HACKING
and the source files protocol3.c/protocol3.h.


Did Creative help you with this?
--------------------------------

No. They didn't help us. We did everything by reverse-engineering, by
looking at the USB traffic. We did not disassemble any Creative code.
We did ask Creative for support, but they have not offered assistance
in any official capacity. The same goes for Dell.


Programs using libnjb
---------------------

If you want to test and look at some programs that use libnjb, apart
from the samples that comes with the library, check out the following:

Gnomad 2 (Linux, BSD, GNOME):
   http://gnomad2.sourceforge.net/
Neutrino (Linux, BSD, GNOME - also makes the njbstack for GNOME):
   http://neutrino.sourceforge.net/
Creative Nomad Jukebox KIO::Slave (Linux, BSD, KDE):
   http://sourceforge.net/projects/kionjb
Nomad Media Manager (Linux, BSD, GNOME):
   http://nomaedia.sourceforge.net/
Nomadsync (Linux, Windows):
   http://nomadsync.sourceforge.net/
XNJB (MacOS X):
   http://www.wentnet.com/projects/xnjb/
KZenExplorer
   http://kzenexplorer.sourceforge.net/


Feedback
--------

Send feedback to the user and developer lists at Sourceforge. You may
subscribe to this list through the project web page, see:
http://sourceforge.net/mail/?group_id=32528


User community
--------------

For generic information on the Creative or Dell devices, see these
Wikipedia entries:

http://en.wikipedia.org/wiki/Creative_Nomad
http://en.wikipedia.org/wiki/Creative_Zen
http://en.wikipedia.org/wiki/Dell_Digital_Jukebox

For a user-supported community of high quality, see:

http://www.nomadness.net/