empeg.com Car Radio

Gregory Alan Bolcer (gbolcer@endeavors.org)
Mon, 15 Mar 1999 14:35:11 -0800


Now that's a better approach to how they do it now.
Digital radios, about time. Just imagine grabbing
songs as you like them, writing your own Python
smart agent. Now that's a programmable car radio

Greg

empeg.com

The unit uses a Digital/Intel
StrongARM processor running at
220Mhz, which provides enough power
for MP3 decoding, plus plenty of spare
capacity to deal with future standards
as they arrive. It's got 8Mb of memory,
plus flash ROM to store the bootstrap.
Up to two 2.5" laptop drives can be
fitted to the shock-mounted cradle
inside the unit: with current drive sizes,
this gives up to 28Gb of storage -
although the PSU and hardware is
capable of handling 4 drives (56Gb!)
there isn't enough vertical room in the
box for 4 drives. Maybe later :-)

On the audio side, a custom in-car DSP
deals with the DAC and provides
digital loudness, bass, treble, balance
and fader for the four outputs. It also
gives a separate 5-band equaliser for
each of the four channels.

The decoder software can cope with
MPEG 1, layer 3 compression as well as
the higher quality (and less
compressed) MPEG 2 formats. We plan
to expand this as standards shift and,
as it's all done in software, there's no
getting left behind with out of date
hardware.

On the front of the unit there's a
graphic vacuum-fluorescent display,
giving a sharp, clear, high-contrast
information readout. Apart from
showing you what tracks are playing
and letting you browse the menus, you
can turn on visualisation mode using
Orogenic's Prolux to give you spectrum
analysers and plasmas that move with
the music.

Also on the front is both an IrDA
transceiver and a consumer-IR receiver,
which deals with both the IR remote
and also with talking to things like
palmtop computers. Currently, there's
no software to talk to devices like the
PalmPilot, but we hope some madman
will write some and we'll help where we
can.

Round the back live the serial
(230,400bps max), USB (12Mbit) and
home power-in jacks, plus the docking
connector for the in-car mount.

Why Linux? Well, it provides a good
support environment for the unit's
software, and is solid and reliable. We
also like it a lot, and worship Linus on a
daily basis at our own personal shrine.
Not that we're obsessed, or anything...

People have asked about making the
unit more open. At the start, we don't
have the manpower to offer this sort of
thing, but it is planned to release a
setup which will allow logins, and be
configured with gas and gcc for users
to develop their own software on the
unit. However, there will be no support
for this - you have to be serious about
it, and happy with Linux and software
development in general for this to
appeal to you. In the worst case, you
can always reinstall the default
software - the boot code is protected,
so you shouldn't end up with a dead
unit.

The unit's UI is written in Python,
allowing Python-esque users to add
features and giving great flexibility in
the way the unit works.