Homepage of Stefan Salewski
Projects
Here are some of my projects listed -- in reverse chronological order.Digital Storage Oscilloscope (DSO)
Since some years different companies sell small little boxes, which can be connected to PC or notebook computers by USB or Ethernet and can than be used as a Digital Storage Oscilloscope (DSO). Although the principle design of such a device is no secret and different project proposals for the construction are available, no complete schematics can be found in Internet. My own (not fully finished) schematics and a short description are available here:
My principle goal is to build a few prototypes and to offer some minimal, open-sourced software under free GPL license.
My draft of a simple and cheap, but untested analog input stage for a DSO is available here:
Footprint generator for PCB
I have written a plain command line driven footprint or "land pattern" generator for the PCB-program of the gEDA collection of free software tools for Electronic Design Automation (EDA). It is written in Ruby, see this page for more information:
A simple Ruby script for fixing gEDA schematic symbols
USB -- Universal Serial Bus
Free, open-sourced firmware for Atmels AT90USB microcontroller
The USB is the prefered method to connect various microcontroller-circuits with a modern PC.
I build an experimentation board for the 8-Bit microcontroller AT90USB1287 (AVR) of Atmel corporation and developed a free USB-firmware (GPL) for this controller. The operation of the firmware is demonstrated with a small application program, which uses the internal Analog-to-digital converter of the AT90USB chip to record an analogue electrical signal, and sends the measurement data over USB to a (Linux)-PC.
More information about the experimentation board (schematics, pcb layout and bill of materials) can be found here: A detailed description of the USB firmware is available here: Alternatively you may go directly into the source-text directory: