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Car-PC Project
In summer of 1999 I got an interesting piece of PC hardware: a Kontron industrial PC. It was a seriously built 386 in a magnesium enclosure and with goodies such as a DC power supply, TFT color display and ISA bus expansion slot. I decided to install it into the Saab. Soon I realized that I would have to move the components into a more appropriate enclosure and hide it away. And that is how I got started with this project which has occupied a lot of my freetime lately. I haven't been working on it in a hurry: the project is simply recreational. This page is about reporting the current status of the project and I've included some photos you may find interesting if you're working on a similar project.
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Hardware almost completed. Software under development. The system will be installed in to the car in fall 2000.

Components Last Update 6th September 2000
Here's a list of components I've gathered for the project. Where appropriate, I've mentioned the part source and price as well. Most of the parts, however, are saved from being scrapped.
PhotoComponentSourceEst. cost (€/$)
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Kontron IN-Lite PC  
Although old (from 1993) this is quite a piece of hardware: An Intel 386SL/25Mhz based PC with 8 megabytes of memory. The motherboard features built-in IO ports (including SCSI), PCMCIA slot, and an embedded 120 MB hard disk. The unit has a DC 18-30V power supply (I'm using a 12 to 24V power converter to power the PC from the battery) with internal backup battery (15 mins). The floppy drive is very small footprint. The other highlights include a 12" TFT Color display and ISA expansion slot. This Kontron PC has an advanced diagnostics capability including an additional LCD status display reporting component temperatures, input voltages and so on... In case of components freezing or voltage dropping the error is presented in the display and the PC will be protected. The computer was originally assembled in a laptop case made of magnesium. It was neat but wouldn't have suited my installation so I just ripped all the components from the case.

This PC is perfect for the purpose. It is more than powerful enough and the ISA expansion slot and DC power supply are vital features. You're right, it wouldn't work as a MP3 player, but that was never my intention.

Other parts visible in the picture are:

  • On the lower left corner: ISA slot expansion card from a Digital DecPC
  • On the lower left corner: Standard LPT expansion card (the mainboard LPT port is dead)
  • At the top: PIC serial bus relay controller, see below
PhotoComponentSourceEst. cost (€/$)
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Click for a 800x600 pixel photo in a separate window
Enclosure (Microtek Scanmaker II)  
This is funny: I was looking for a proper enclosure to build the PC into. At the same day I was completely pissed of because my old Microtek scanner was acting up again. I came up with the idea of sacrificing that old POS for a good cause and so the scanner was dissassembled and I got a very nice enclosure to build the PC into. The case is made of plastics but coated with EMC protective copper paint from the inside. The holes I cut with a Welleman plastic welding kit. The case was painted gray with spray can, using plastic primer first. The scanning plate, made of glass, now serves as the front panel. It is now covered with black plastic film, except for the openings for the TFT and diagnostics displays.
PhotoComponentSourceEst. cost (€/$)
  Console Probyte Oy, Tampere Finland 40.-
Since I was going to hide away the PC I would have to make a separate console. I was first going to use the 12" TFT display but soon realized it is way too large to fit in the dash. So I bought a 4x20 characted back-lit LCD panel from Probyte. It is interfaced into the PC via the parallel port. I also needed key controls, and for that purpose I scrapped a standard keyboard and kept the controller board.

  IO: inputs: ADAC 5516DMA Adac Corporation  
Since the PC has a standard ISA slot, I will be using ADAC's 5516DMA data acquisition board for the signal input.

  IO: outputs: Probyte SmartDriver16 Probyte Oy, Tampere Finland 40.-
Because there was no room for an additional relay output board and since I wanted to install the relays into the engine compartment to avoid extra wiring I bought a PIC-based relay controller from Probyte. It connects to the serial port of the PC and can control 16 relay outputs.

Temperature sensors: Dallas DS1820 Probyte Oy, Tampere Finland 6.- each
These are very cool components! They're completely stand-alone temperature sensors which can be connected into a serial bus leading to the PC serial port. A query sent to the bus from the PC will return the temperature reading of the desired sensor. Here's a link to another project using these chips: source codes are included.

Click for a 800x600 pixel photo in a separate window
Click for a 800x600 pixel photo in a separate window
Click for a 800x600 pixel photo in a separate window
Assembly Last Update 6th September 2000
I don't think these photos need much explanation. Assembling the components into the scanner enclosure was quite a task, but I think the result is quite satisfactory. It will be bolted into the rear of the backseat, into the trunk of my Saab. The console panel is laser-cut from stainless steel and has the same look as the rest of my dash panels. The hole in the left is for the extra boost gauge on my dash. This panel will fit the extra DIN opening in the center console.

Programming / Features Last Update 6th September 2000
I'm programming the PC using Borland's Turbo C++ 3.0 for DOS. I'm using DOS 6.22 as the operating system because it is very simple and still powerful enough. It is also important that all the driver libraries required by my components are available for that particular environment. These libraries include: Here are the features I'll be implementing into the first version:
  • 5 temperature sensors picking the temperatures in various locations: outside air, intake air, intercooler core, air temp at throttle body, cabin temperature
  • Intelligent intercooler fan control triggered by the temperature sensor readings
  • Programmable boost level control: low-boost mode while engine is cold, high-boost while readings are ok, low boost if overheating
  • Speed sensing
  • Trip computer functions: average speed, current speed, acceleration time calculations
  • Logbook function: driving time and distances for my records
  • Data transfer to desktop pc using floppy drive
These features are a bit more difficult to implement, so they're planned for the "2.0" version next summer:
  • Fuel consumption sensing
  • MPG calculations and estimations
  • Cruise control
  • Intelligent cabin temperature control
  • GPS positioning and GSM data connectivity
  • Integration to the theft alarm (SMS alerts)
Before implementing these features I will have to get familiar with flow meters (I doubt I can use injector pulse calculation as the fuel flow measurement signal since the turbo engine has a variable fuel pressure) and stepper motor controls (cruise and climate control). If you know good sources of information covering these subjects, please let me know!

All materials Copyright © 2000 Jouko Kuisma