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Data Acquisition Unit

The Data Acquisition Unit was the most difficult to develop hardware part of the BlueEyes system. Because we wanted to make it a truly mobile device we had to squeze quite a lot of hardware into a fairly small box. Here's the DAU development story...



To acquire the Bluetooth transmisison technology we first built a "distributed" version of the Data Acquisition Unit, which was not mobile at all. The core of the system was a universal Phlips 80C552 microcontroller board.

To be able to communicate with the "outer (real?) world" we developed an I/O board featuring:

  • 32 kB of external RAM memory
  • I2C interface
  • LCD display
  • RS232 serial port
  • debug LEDs
  • small keyboard

The I/O board was of course connected to the microcontroller board.


As the Philips 80C552 has no Flash EEPROM we had to execute the microcontroller software using an (self-made of course) EEPROM emulator.

The microcontroller binary program is loaded through a parallel port, then - the emulator resets the microcontroller and the new program is being executed.


Finally, we connected one of the precious Bluetooth modules to the rest our machinery.

After weeks of tests, we developed the main DAU software (rougly over 4 KLOC of 8051 microcontroller assembler code)


After the microcontroller software reached a more or less stable state we started to develop a mobile version of the device.

The best thing to start with is a PCB (Printed Circuit Board). This one contains:

  • Atmel 80C52 microcontroller (ran at 22.1184 MHz)
  • power supply
  • LCD display, ID card, keyboard and Jazz sensor interfaces
  • MAX232 for RS232 communication and Bluetooth module interface

Here - the biggest fun starts - squeezing all the parts (microcontroller main board, Bluetooth module, PCM codec board, Jazz interface board, ID card interface, batteries, LCD display and LEDs) into the box (18x11x6 cm).

We started with drilling holes (for the LCD display and the ID card interface) in the bottom of the case and placing blocking elements.

  In the top of the case LCD display, keyboard and LED diodes were mounted.
  Just to connect everyting with some cables (note that under the PCM codec board there is the ID card interface and under the microcontroller board there is the Jazz interface boards), and ...
  ... we are ready to close the box ...

... and to turn it on.

It didn't blow up !

Moreover - it works and (as expected) wants an ID card (which is a separate story). Well done !


copyright - BlueTeam - 2001
web design - Stanislaw 'STACHOO' Osinski Krystian 'ZAK' Nowak