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Programming AVR I2C interface. I2C (also referred as IIC or TWI) is widely used interface in embedded applications. Two wire bus initially was used by Philips and become a standard among chip vendors. I2C bus consists of two lines called Serial Data Line (SDA) and Serial Clock Line (SCL). Communication is relatively fast and short distance mainly used to communicate between sensors, RTC, EEPROM, LCD. I2C protocol allows up to 128 devices connected to those two lines where each of them has unique address. Communication between devices is master and slave based. Master generates clock signal, initiates and terminates data transfer.

From electrical point of view I2C devices use open drain (open collector) pins. Each communication is initiated by START signal and finished by STOP. Bus is considered to be busy between START and STOP signals. I2C communication packet consists of several parts: START signal; Address packet – seven address bits lead by data direction bit (read or write) + acknowledge bit; STOP signal. Read.

PIC

Le forum officiel PICAXE francophone - PICAXE Forum. Technopujades.free.fr - La technologie au collège. Initial review: mbed LPC1768 Development Board. In this article we review the mbed NXP LPC1768 development board and the mbed system in general. Introduction Today we will examine the mbed NXP LPC1768 development board. The goal of the mbed system is to “provide(s) a platform for microcontroller hardware, tools, libraries and resources designed to enable rapid prototyping with microcontrollers.” ( Personally I also see this as a good option for a “next step” for those who have outgrown their Arduino – the mbed offers much more processing power, a similar development environment and similar hardware ease of use.

The NXP LCP1768 MCU on our mbed board offers the following specifications: For a full description and data sheet, please visit: Although a small project started by two ARM employees, the mbed has proven to be a worthy product to allow people of generally all skill levels access to powerful microcontrollers without a lot of the inherent complications.