Stepper motors translate digital switching sequences into motion. They are used in printers, automated machine tools, disk drives, and a variety of other applications requiring precise motions under computer control. Unlike ordinary dc motors, which spin freely when power is applied, steppers require that their power source be continuously pulsed in specific patterns.
3 axis stepper motor driver using a single RS-232 port
Fred Sigernes – Optics Spectroscopy Electronics
“Currently I am hired as Professor in optics and atmospheric research. In addition, I am chief of the Kjell Henriksen Observatory at UNIS.”
The gEDA project has produced and continues working on a full GPL’d suite of Electronic Design Automation tools. These tools are used for electrical circuit design, schematic capture, simulation, prototyping, and production. Currently, the gEDA project offers a mature suite of free software applications for electronics design, including schematic capture, attribute management, bill of materials (BOM) generation, netlisting into over 20 netlist formats, analog and digital simulation, and printed circuit board (PCB) layout.
gEDA Project – Electronic Design Automation tools
The gEDA project was started because of the lack of free EDA tools for UNIX. The tools are being developed mainly on GNU/Linux machines, but considerable effort is being made to make sure that gEDA runs on other UNIX variants. For a complete list of freely available tools please be sure to visit Open Collector.
GEDA Projects External
CompuPhase articles and Application notes
On-line publications “for programmers”; they are also written “by programmers”.
CompuPhase develops electronic designs, printed circuit boards, prototypes of custom apparatus and the embedded software that runs on the devices.
Examples of such apparatus are the various LED-panels that we set up in several exhibit centres, under contract of Podium (Netherlands). Embedded systems
CompuPhase Services include contract programming of applications and embedded systems, and also the design and production of custom electronics.
CompuPhase Projects and Programmable MP3-player
On the right is a Programmable MP3-player for scale models, broadcast systems and special applications.
High quality audio, based on a 24-bit D/A converter with 8× oversampling digital filter, low noise and low distortion.
SDCC was written by Sandeep Dutta and released under a GPL license.
SDCC – Small Device C Compiler
SDCC is a retargettable, optimizing ANSI – C compiler that targets the Intel 8051, Maxim 80DS390, Zilog Z80 and the Motorola 68HC08 based MCUs. Work is in progress on supporting the Microchip PIC16 and PIC18 series. SDCC is Free Open Source Software, distributed under GNU General Public License (GPL).
- ASXXXX and ASLINK, a Freeware, retargettable assembler and linker.
- extensive MCU specific language extensions, allowing effective use of the underlying hardware.
- a host of standard optimizations such as global sub expression elimination, loop optimizations (loop invariant, strength reduction of induction variables and loop reversing ), constant folding and propagation, copy propagation, dead code elimination and jump tables for ‘switch’ statements.
- MCU specific optimizations, including a global register allocator.
- adaptable MCU specific backend that should be well suited for other 8 bit MCUs
- independent rule based peep hole optimizer.
- a full range of data types: char (8 bits, 1 byte), short (16 bits, 2 bytes), int (16 bits, 2 bytes), long (32 bit, 4 bytes) and float (4 byte IEEE).
- the ability to add inline assembler code anywhere in a function.
- the ability to report on the complexity of a function to help decide what should be re-written in assembler.
- a good selection of automated regression tests.
The SDCC Open Knowledge Resource
Cygnal (Silicon Labs) 8051 Port
The Cygnal port was developed on a C8051F120-TB prototyping board (instructions are provided should you wish to use an alternative development board) fitted with a 8051F120 microcontroller. The freeware SDCC compiler was used along with the Cygnal IDE.