The controller is actually just an ATTiny2313, running of it’s internal RC oscillator at 8MHz, soldered onto an universal board with a few resistors and wires. There are no control items - no buttons, no nothing. It just does what it does - makes the effect of LEDs randomly fading in and out using 9 channels of PWM. Unfortunately, the processor has only a few hardware PWM channels, so some of the channels had to be done by software.
Before starting this Ethernet project the author did of course some prototyping and then he noticed alreadythat UDP was not a problem with lots of space left on the atmega88. Therefore he was quite confident that TCP + HTTP will work. TCP/IP was invented more than 25 years ago. Todays microcontrollers provide almost the computing power a standard computer had at that time. No java or xml was used at that time. Things were done in smart and efficient ways.
As you can imagine this web-server code is written for a friendly environment. Don’t put it on the open internet. The code uses e.g the incoming packet to build from it the outgoing packet. An attacker who sends a mal formed IP packet might be able to confuse the TCP/IP stack. The code is verified with a lot of different browsers and a number of operating systems. It was tested Linux, BSD Unix, Win 98, Win XP, Mac OS-X with a number of different web browsers. It works very well but it was not tested agains atacks and destroy tests.
What is Ginger ? Ginger is yet another physical computing platform, which is similar to gainer (http://gainer.cc). The goal of project is to develop PC Platform
Ginger makes use of avr-usb (http://www.obdev.at/avrusb/) for the implementation of USB interface. Thanks to avr-usb, no external USB-serial bridge chip is required to interface host PC, and this makes ginger hardware simple. ATmega88 is chosen because it is available in AKIZUKI-denshi, where many electric parts are sold in bargain price.(We love the store).
In Macintosh platforms, you don’t need to install software drivers, as the device is recognized as /dev/cu.usbmodem*. In Windows, please use ginger.inf provided with source code in tarball.
This simple circuit is designed to report the temperature via any standard FM broadcast band radio at regular intervals. It uses a simple low bit rate tone signalling scheme which can be interpreted easily by both humans and machines. Such a device can be used stand-alone or as part of a PC-based weather station or HVAC system.
There are endless practical applications for such a device, just think about how many time you wanted to measure a temperature and for that you needed to run wires to the sensor. Now with this circuit you can place the device where you need the temperature reading and no more wires need to be connected.
The LM35 of National Semiconductors that is used in this project is a precision centigrade temperature sensor, which has an analog output voltage. It has a range of -55ºC to +150ºC and a accuracy of ±0.5ºC . The output voltage is 10mV/ºC . The output voltage is converted by the AD convertor of the ATMega8. The temperature is displayed on an LCD module. In this example the thermometer has a range of 0ºC to 40ºC and a resolution of 0.5ºC. If you want to have a readout in Fahrenheit you can use the LM34.
LM35 Based Thermometer Display Temperature on LCD:[Link]
