Last updated Sep 15th
Car MP3 Player by Jeff Mucha
I designed a microprocessor shut down controller This unit will detect the voltage at the battery and it has a temperature sensor that makes sure the computer is going to turn on in a safe temp range it is available now at www.mp3car.com if you want to buy one.
Check out a new gadget I invented for the christmas tree. This is a review I wrote for a product I invented (so Yaa it's biased...) and I'd like to see it get into retail stores for Christmas.
I am now selling MPBS1 Power Supplies to fellow hobbyists. The power supply seems to be one of the biggest stumbling blocks when implementing a car computer. This power supply will work for many applications but I don't sell many of them and that is why I have to ask what I ask. The component prices along with all the labor it takes to build them drives the price up. I do it because people make some pretty cool boxes with my design and that satisfaction is pretty cool. Purchase an MPBS1 Power Supply!
Here is the AC waveform measurement data
I Just bought a PLL based FM transmitter. This is far better than the ones that have a tuning dial because it locks on to the exact frequency. It has very good audio frequency response and only cost 25 dollars. The crummy ones will drift in frequency. I took the thing apart and it has a microprocessor and a quartz crystal along with what I imagine is a pll synthesizer which has the markings scraped off. They probably wanted to keep the design from people like me :-) I highly recommend this as a way to connect to a CD player that doesn't have aux in or if your mp3 player has buzzing coming in over the RCA jacks. Or if you just want it wireless!!
Click This Link and then click on MP3/VCD/CD Player on the upper left of the page. At the bottom you will see the Link-it FM Transmitter.
See some really cool pictures of Mpegbox3 and my setup with GPS, Crummy FM Transmitter, and Sony PSone display. Cool low light Shots
See a graph of how much typical processors use for power. The MPBS1 can only supply 25 watts of CPU power. CPU_power
See pictures of the new mpegbox3 with
the custom MPBS1 DC-DC Power Supply! I finally got a new Digital camera! Mpegbox 3
MpegBox 2 was stolen last night
(june 17-18) If you find it, I will give you a reward and be very grateful. Corvallis OR Police Report # 01-6017
systems are nothing more than a PC motherboard with lots of onboard
features packed into the smallest case I could make in my garage.
Each system can hold a number of MP3s relative to the size of
the hard drive I decided to use. MpegBox was screwed together
on an oak frame, when I came around to building MpegBox 2, I
found acrylic cement at the local glass shop.
This page is dedicated to a project
I started on in 1998. I have made two of these "Plexiglass
Computers." The first of which runs off of 120V AC and the
second one runs off of 12V DC. I call these machines "MpegBox"
and "MpegBox 2"
- This page is dedicated to the design
and ideas in building and configuring MpegBox 2 - The Car MP3
Player / Plexiglass Computer.
Here you can see the main components to this mp3 computer.
The Physical dimensions of MpegBox 2 are 9.5" by 9.5"
The top is held on by four screws that were tap and threaded
directly into the Plexiglass.
All the ports to this box come off this panel. When the system
is used in the car, the ports that are used are: Keyboard, Sound-out,
Parallel, and 12V Power.
- More Views:
Here is a picture of the complete system for use indoors:
Here is a picture of the LCD in action:
- The Plexiglass Mpeg Box is nothing more than a PC with all
the guts crammed together as tightly as possible. I chose a motherboard
that has "on board everything," tethered an LCD display
connected to the parallel port, wired up an X10 MouseRemote RF
receiver, wired up the necessary power supplies to the AT power
connector, and made an I/O plate with all the connectors attached.
To do this project I decided that I wanted to find a motherboard
that had at least on board sound, ethernet, and video. I found
the Amptron 585LMR. This
board is of the baby-AT form factor, which means it has the AT
power connector as well as connectors for most of the I/O ports.
It measures 8.5" square and supports socket 7 CPUs.
Here is a system based on the FV24 that is almost just like Mpegbox 3 and it is only $250!
SHUTTLE SV24 VIA VT8363A INTEL SOCKET 370 READY FLEX ATX BAREBONE SYSTEM
- Power Supply:
Here is a power supply I have designed for the next generation
mpegbox: MPBS1 DC-DC ATX Power
- I got two laptop power supplies from Marlin
P Jones. When I bought them, there were only a few hundred
left so I hope they never blow out. Here is the spec sheet for
the AA90304.txt by Astec.
- I wired up the power supply so one of the laptop supplies
powers the motherboard and one powers the hard drive. I ran the
system off of one power supply, but the 5 volt line draws power
very close to its limit of 3.5 Amps and the one power supply
got very warm. By using two of them, neither of them get very
warm and it does a pretty good job. I had to isolate the individual
connections because with both power supplies connected in parallel,
one power supply would over current at startup and shut it's
- I also under clocked my CPU. You don't need more than a 486
to play MP3s so I took my spare Pentium 233 and under clocked
it to 133. This saved quite a bit on the power draw. The complete
system draws about 35 watts or about 3 amps at 12 volts.
- If you want to power your system with a standard power supply in
a car, get one of these. This will be able to power any system from a 12
volt lighter outlet.
Tripp-Lite 12 volt Power Inverters.
- Since I had to make my own wiring harness to my system, I
found the following information useful.
ATX Power Connections:
(with color codes)
AT Power Connections:
(with color codes)
comes with a wireless RF interface to the computer. It will connect
to the PS/2 port or the serial port. There are plugins that work
with WinAmp that use the serial port of the computer to interface
the MouseRemote. I did not have much luck using the serial port
on my machine so I hacked together the PS/2 interface and hard
wired it to the PS/2 port of my motherboard. You can see the
circuit board in the top view picture above.
I paid 30 bucks for my MouseRemote, it looks like they jacked
the price to 50? I'd wait for a sale to get another one of these.
This is the Mouse Remote from X10 >>
<< Here is an image of the RF receiver on MpegBox 2.
It is a good idea to use hot melt glue to "strain relief"
connections made to circuit boards so the wires don't get stressed
and break off.
- LCD Display:
- The LCD for MpegBox 2 is a standard backlit 40x4 character
display. I bought it for 15 dollars from TimeLine.
I wired it up using lcd.GIF below as a guide.The 40x4
display has a 16 wire interface where as the 20x4 has a 14 wire
interface. The difference is the second Enable line, 40x4 displays
have two Hitachi HD44780 controler chips on them. On standard
LCDs, pins 1-7 are data, pins 9-11 are control, pin 12 is contrast
adjust, pin 13 is ground, and pin14 is 5 volt power. If there
are two controler chips on the LCD ie. the 40x4, pin 15 is also
a control line. All the data and control lines can be wired directly
to the parallel port of a computer. Go here
for more details of how to implement an LCD display.
- In order to make a connection from the LCD to the computer
you need to get 5-volt power. Most parallel ports do not supply
enough power to operate an LCD. I decided to use the keyboard
connector to power my LCD. I have a cable that goes from the
keyboard connector to the parallel port connector, and then a
cable that goes from the parallel port connector to the display.
for the pinout of the PS/2 and AT connectors. To connect my
LCD, I found that I need at least 14 wires to go to the 40x4
display (contrast is controled with a potentometer at the LCD).
I was able to find some cable that had very small wires. The
cable is only 1/8 inch thick and has 16 separate wires in it.
I got the wire, AT keyboard connector, and parallel port connector
all from the local surplus electronics shop. The LCD is enclosed
by an anti-static bag because I could not think of a better solution
that would not be big and bulky. It does a very good job of insulating
the LCD from everything but it doesn't look as nice as it could.
- Operating System:
- When I first decided to do this project I had to choose an
operating system. There are tons of choices and all of them have
their advantages. I am a fairly novice Linux user and most of
my friends told me I should use Linux or some flavor or embedded
Linux. There are single disk distributions of Linux and bla bla
bla.. I decided to use Windows, (I know, blah blah... I'm a sellout
and the whole bunch..) I did a Win98Lite install and started
to hack it down to save time at startup and avoid problems with
windows in a non-monitored system. I admit, Linux would be a MUCH
BETTER SOLUTION if I had the time to learn enough about it to the point
where I could do the same things I did in windows. You would want a hacked
down version of the kernel with networking support, RF mouseremote
support, and the works.
- Reasons Why I Chose Windows:
- WinAmp is freeware and LCD drivers are already written for
- Batch files with playlistes are easy to make and use and
associate to keys on the MouseRemote.
- The drivers for the MouseRemote work and are already written.
- It is very easy to update all the music files whenever I
want by plugging the box into my local network and having a batch
file that will either boot normal windows or boot hacked down
- Things I did to speed up the boot-up process (Hacking
- Turn Off ScanDisk and Disable Splash Screen:
- Add or change these lines in the msdos.sys file:
- By setting AutoScan to 0 it disables ScanDisk at startup.
By setting Logo to 0 it gets rid of the splash screen (Windows
9X) at startup. I have used this box in my car for 2 years and
I brought it inside and ran scandisk on it one day and it didn't
have any errors from being power cycled (instead of being shutdown).
- Don't boot into Explorer:
- Edit your system.ini file:
- Instead of booting into explorer when Windows comes up, I
have it launch WinAmp and a playlist in this example. You can
replace what comes after "shell=" with a batch file
and have it do whatever you want, load anything you would have
loaded in the startup folder, etc.
- Copying files over the network:
- One thing I like about windows is the built in networking.
I set up a batch file that copies a version of system.ini that
has the explorer launched when I want to copy files from the
network or make system changes in Windows, upgrade WinAmp, etc.
To do this, I plug the machine into the network, plug in a 12
volt supply, plug in a mouse and keyboard. I hit F8 at startup
and tell it to boot to command prompt. I then run bootwin.bat
and it makes that change and loads windows.
- If you set up file sharing, you don't need to have Explorer
running, you can plug in the box to the network and have the
box still function stand alone while files are being copied to
or from it.
- Example Files:
- File info:
- Bootamp.bat: This batch file copies the iniamp.ini
file to system.ini in the Windows directory.
- System.ini: This file is the backup of system.ini
that loads windows as normal.
- msdos.sys: This files shows the changes to turn off
scan disk and kill the splash screen.
- Bootwin.bat: This batch file copies system.ini into
the Windows directory.
- Autoexec.bat: This shows how lcdprint.exe can be used
to display a startup screen on the LCD.
- lcdprint.exe: This is a program that will print a
text file to the display, useful for LCD startup screen and testing.
- Hello.txt: This my txt file that gets printed to the
- lcd.gif: This is the hookup diagram I found on the
- vis_LCDi.ini: This is my config file for the LCD WinAmp
- visLCD572.zip: This is the plugin for WinAmp. The
latest version of the LCD display WinAmp plugin can be found
- Cost and Parts:
- Here is a breakdown of the
associated with my Car MP3 Player. I'm sure most of these prices
will have changed by the time that you read them, so take it
for what you will. If you make one of these, expect to spend
about 300 bucks on hardware along with countless hours
of your time. Depending on your operating system and software,
that can run you from free to hundreds of dollars.
- LCD Displays and
other stuff : EIO
- Electronics Parts :
- More Electronic Parts
: Electronic GoldMine
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The author of this page is
not responsible for any damages caused by someone following the
procedures listed above.
This page is presented for entertainment purposes only. All claims
are made from experience and are not necessarily fact.
Various trademarks on items are the property of their respective
Send comments or corrections to: Jeff
©2001 Jeff Mucha. All Rights