Since we’ve been busy adding quite a few I2C sensors and breakouts lately, I thought this technical overview of the 2-wire “Inter-Integrated Circuit” bus might be handy. I2C isn’t fast (typically limited to 400kHz in most real-world situations), but it’s convenient since it only requires two pins and more than 120 devices can be connected on the same bus, address space permitting. For low-pin count devices, it can be a real life-saver since you can hook an OLED display, a DAC, a 7-segment display and 16 servo motors up to your Arduino with a measley two pins and some careful coding! The full bus specification is available from NXP in UM10204 – the bus was created by Philips, whose semiconductor branch later became NXP — but the more concise information from Embedded Systems Academy might be easier to digest as a starting point. The FAQ has some very good information in it.
I2C Bus Technical Overview – [Link]
In this project we introduce easy to build, miniature servo controller. This miniature servo controller system is ideal for most of the robotic and mechanical projects. Some of the most notable key features of this project are:
- Tiny PCB design (35mm × 33mm aprox.) using standard through-hole components.
- Support for both analog and digital control interfaces.
- Compatible with most of the servo units.
- Low cost due to small amount of components.
Mini PIC12F675 Servo Controller – [Link]
Ejberg.dk has developed this project for a simple ATtiny2313 based servo tester.
This device lets you test servos by varying the pulse width between limits of 0.8000 ms and 2.2000 ms selectable through the use of four buttons.
While the schematic shows an Atmel AT90S2313, the circuit will work with the popular ATtiny2313 using version 2.05 of the code downloadable from the ejberg site. He also has another version of this tester known as the ServoTester2 which uses the ATmega16P.
ATtiny2313 based servo tester – [Link]
Chris @ PyroElectro.com writes:
Searching for a reliable wireless solution for your project can be a real pain if you’re not familiar with current wireless standards, data rates and reliability. The Xbee Modules that we will use in this article are widely available, use a very reliable wireless transmission protocol and have sufficient datarates for most hobby projects.
This article will show you how to build a basic wireless input and output system in the form of a single transmitter and single receiver. Communication will be one way to keep things simple with two xbee modules being used for the wireless link. In the end, a small trimpot will control the movement of a servo motor.
Xbee Wireless Servo Control – [Link]
This is just a quick video showing that you can power an AVR project from a fried servo or an old emergency cell phone charger.
Arduino Project Alternative Power Sources – [Link]
I believe that kids (and not only kids) that have their hands on electronics, wanted at least once in their lives to make an electronic keylock system for their house or room. When i was a kid, i had bought a Smart Kit Keycode lock system, and i had adapted it on the external door of my house. But this door had already the automatic-release mechanism. I only had to find which wires actuate this mechanism and hook the relay of the kit in parallel to this.
Then, i discovered that making a key-code circuit, is simple, very simple. As a matter of fact, so simple, that i designed this very simple key-code circuit, similar to the one from smart-kit but much better (mine had automatic reset operation when wrong code was entered), which took me only a few hours to design. Not to mention the microcontrollers… But why don’t i have a keycode-lock for my apartment’s door? Simple because it is expensive and needs a great mod on the door or frame.
Servo-Actuated Door Keylock Hack with capacitance touch-pad – [Link]
The servo motor is widely used in model hobbyist such as airplane R/C model for moving the rudder, ailerons, elevators and acceleration control or in the car R/C model for steering and acceleration control. In this tutorial we will learn how to control the servo motor as well as the simple close loop control algorithm for this servo motor.
The servo motor basically is a high quality geared DC motor equipped with electronic circuit for controlling the DC motor rotation direction and position. Currently there are two types of servo motor available on the market, the first one is called standard servo and the other one is called continues servo; standard servo can rotate to maximum (clockwise or counterclockwise) of 120 to 180 degrees while continues servo can rotate up to 360 degrees in both direction.
Basic Servo Motor Controlling with Microchip PIC Microcontroller – [Link]
Simon has created an servo switcher for use on autonomous vehicles. designed to allow manual control if the autonomous controller fails. Using a pic12f683 and 4066 analog switch. source code and board files are available on his website.
Autonomous servo switcher – [Link]