We want to show you how to use the popular Arduino to produce a device capable of recognizing passive transponder (TAG). But this is not the usual RFID key, because the system can activate a relay if a recognised TAG is read, but also we took the opportunity to make an application that use cloud-computing. The basic version, which is a simple key relay consists of an Arduino and the RFID shield based on a ID-12 of Innovations: placing a transponder already learned, the relay is activated. The extended version of our project uses an Arduino, the RFID Shield and the Ethernet Shield with which we can access the Internet and stored, using the Google Docs service, the transponder data.
Arduino RFID shield on the Cloud - [Link]
A lot of people who bought the TiDiGino ask me how to test it. The Gsm Remote Control is provided with bootloader, so you have to insert the prefered sketch that you can find in code.google. Daniele Denaro wrote a good sketch for TiDiGino, and I’m reporting his tutorial. Ask me (and him) all do you need.
Author Daniele Denaro
Be careful, because you have to manipulate the environment of development (IDE) 1.0 to insert the new hardware. In particular replace the file “boards.txt” (see below). In this new version of the file has been added to the section on hardware TiDiGino. You should also add the folder “tidigino” that “boards.txt” references (see below). The changes will be visible to restart the IDE.
Software and firmware for TiDiGino - [Link]
Kerry uses a DIY serial display to show debugging data sent from an Arduino’s UART. Sometimes the data comes too fast to read, so he added a 4K buffer and controls to scroll thorough the history. [via]
…if your application generates a lot of messages, it would still be hard to spot the relevant information as you can only see the last couple of lines of the data.
So my solution is to add a none-volatile off-screen buffer to the serial display so that multiple rows of data can be captured during run time and retained for later debugging.
Serial port monitor with 2×20 LCD and 4K text buffer - [Link]
I wanted to make an easy and secure way to enter my garage. RFID was the best way to unlock my door, even with my hands full I can unlock the door and push it open! I built a simple circuit with a basic ATMega 168 arduino chip and a ID-20 RFID reader to control an electronic door lock.
The circuit consists of 3 separate parts, a Reader to read RFID tags, a Controller to accept data from the reader and control the output of the RGB LED and the Electric door lock. The door lock is first installed in a door and tested with a 9v battery to ensure correct installation. In most cases you want a Normally Open circuit on the door lock, or Fail Secure. This means the door stays locked when no current passes through it. When 12vDC is passed through the electromagnet in the door lock, a plate in the lock gives way and allows the door to be pushed open freely.
Arduino RFID Door Lock - [Link]
This segment is the latest in a series of Arduino tutorials posted by Tronixstuff.
Tutorial: using Ping ultrasonic sensor with Arduino - [Link]
Digital pins 0-7, Analog 2-5, and a RST, V+, and GND pin are broken out to two rows of pins, maintaining about half the pins in a familiar shape and organization. A JST connector for LiPo batteries like the ones available through SparkFun and Adafruit and an MCP73811/2 charger circuit makes the Demiduino well suited for portable applications. On the back, I’ve also included CR1225 clips for ~3v3 power from easy to find coin cell batteries, and a power switch to save battery life.
Demiduino, another tiny Arduino compatible board - [Link]
Eric built himself a battery monitoring system based on the ATmega328 Development Kit. He drained a 9V battery with 100mA of current and monitored the voltage drop until total depletion. He used this data to estimate how much time is left until depletion – [via]
The 100mA constant load was chosen because my ProtoStack Arduino Clone with LCD draws about 92mA and I wanted to write a sketch to display a battery bar and the approximate hours battery life left. Since all batteries have an internal equivalent series resistance (ESR), it is important to take that into account when only using a battery’s voltage to monitor its state of charge. Since we discharged the battery through a load that is similar to the ProtoStack board with LCD, the ESR of the battery has automatically been accounted for in the voltage measurements.
Monitoring battery voltage to calculate capacity with an Arduino - [Link]
Here (machine translation) is a DIY single-layer version of the Arduino Leonardo. The blogger goes into detail on how to build one yourself. Everything is covered from preparing and etching your own DIY board, to fine pitch soldering of the ATmega32u4 IC. Once you have built your board, they show you how to upload a bootloader into the microcontroller.
The Arduino Leonardo is a new platform from the Arduino team that uses the ATmega32U4 uC with built in USB capability. This eliminates the need for the expensive FTDI USB-to-serial ICs and keeps the costs down.
DIY Arduino Leonardo clone - [Link]
If your Arduino project has minimal IO needs, you may want to consider shrinkifying it. This video demonstrates High Low Tech’s method for programming an ATTiny with Arduino code. Maker Randy Sarafan has designed an 8-pin Arduino programming shield to make the task easier. [via]
Shrinkify your Arduino project - [Link]
Don built an Amblight for his home theater PC. He put together this tutorial describing his build of a multichannel Arduino-based Ambilight. He estimates the BOM at $40 (in addition to the Arduino). [via]
The bill of materials include 6+ ShiftBrites (your call, I wouldn’t do less than 6 though), a printed circuit board, wire, and headers. Additionally this will require all of the components needed to get over 0.5 Amps at 5.5-9V DC on to the board to drive the ShiftBrites; this cannot be reasonably done over USB power. My ultimate goal here is to give others some ideas on how to go about this project for less money than it would cost to essentially buy everything in a kit. I went in to this trying to be resourceful and I feel pretty good about how it turned out.
DIY Arduino Ambilight using ShiftBrites - [Link]