December 1, 2010
Special: Embedded Guide 2010
Embedded Beaker!Beaker from the Muppet Show can be built as an interactive puppet and his presence and responses (sort of) enjoyed for all they’re worth. The project is sketched only on these pages and really intended to add a light-hearted note to this December 2010 Embedded Guide. But make no mistake, Embedded Beaker! involves programming a microcontroller and juggling MP3 files, hence is a full blown embedded project.LED Board on ATM18Following on from “Build a Scrolling LED Message Board in One Day” , here in one page (or almost) is how to display a 64 × 32 pixel .bmp image on the aforesaid board. No need for a 32-bit microcontroller for that — our trusty ATM18 module has everything we need for this.USB TO RS485 / RS232 ConverterThe converter described here requires only two chips and a handful of passive parts. The core of the circuit consists of an FT232RL IC from FTDI. The IC includes everything needed to create an RS232 port on a PC that doesn’t have one.XPort(Pro)-to-Breadboard InterfaceAlongside USB, the Ethernet interface is a favourite when it comes to connecting computers to other devices. The Lantronix XPortPro device does the job quite well, besides adding an ultra-compact Linux based 32-bit mini server with many protocols supported. It’s also claimed to be The World’s Smallest Linux Networking Server. The discerning Elektor reader however will want to “switch stuff at home” hence rejoice at … I/O lines!Using Minimod18 to Control up to 256 Servo MotorsCheap radio-controlled (R/C) cars usually have only a single servo motor, just for the steering. In small model aircraft, you typically find two (steering and climb/descend), four is already quite a lot. So who might need to control up to 256 servos?Easy Sceptre Programming with Oberon-07Astrobe is an integrated development system running on Windows which incorporates an Oberon-07 compiler and linker with a powerful multi-window editor and a set of library modules. You can use it to develop applications for the NXP LPC2xxx ARM7 family, which includes the LPC2148 microcontroller used in the Scepter prototyping system. This article describes the structure of an Oberon-07 application and some of the low-level features of Oberon-07 used when programming the Elektor Sceptre hardware directly.PIC-based Lighting Controller with TriacsThe objective of this design project is to generate lighting effects for works of art produced by students and displayed in an exhibition. This involves six 12-volt, 50-watt colored halogen lamps that are rhythmically switched on and off in varying combinations according to a ‘sound-to-light’ scenario in order to achieve artistic effects from the interplay of color, light and shadow.A Graphics Display for the SceptreHere's how to link the Elektor Sceptre 32-bit fast prototyping platform to the colour graphics display for the Nokia 6100 phone (132 × 132 pixel square 4096-colour display with an effective area of around 30 × 30 mm). And the icing on the cake: you can buy ready-made PCBs with this display already fitted.Modular LED Message BoardThe circuit described in thbis article only comprises 64 LEDs and has been designed as the basic building-block of a panel that can be extended as much as you want, in height and width.So each of the building-blocks making up the message board comprises only 64 LEDs. The various blocks are physically juxtaposed to build up the message board.Ground ReceiverAn over-air low-battery warning system for remote controlled models.One Pixel EyeIn this article we show how to make a simple ‘1-pixel camera’ using an LDR and an Arduino. Two pieces of software, one for the Arduino and the other for the PC, are used to control everything.Speed Controller for Small DC MotersInspiration for this design came from the need to drive a Lego model using a small electric motor. The application required the motor speed to be adjustable and capable of maintaining a constant speed under varying load conditions at low speed. The neat solution given here uses an ATtiny44 micro to measure the motor’s back-EMF and control a motor driver stage.