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Grand Prize Winner
(Dec 2012)
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(July 2012)


DefendLineII is ATMega1280-based unit which has open architecture, rich functionality and opensource firmware support. These features make it perfect for wide range of embedded applications: security, monitoring, medical, base for designing of robot-kits of any kind.

The documentation is available at DefendLineII User Guide

Main unit features:

  • Includes Atmel ATmega1280 chip with 128k internal flash program memory clocked by 14.7456 MHz crystal;
  • Power supply: 3.3 Vdc, dual independent stabilized power sources (7-14 V unregulated input as main source, 0.8-14 V input as backup or battery source), interrupt driven power failure detection;
  • Four independent input lines for alarm sensors (PIR sensors, etc) and one line for tamper detection;
  • Two 10A 240 VAC relay outputs;
  • Four hardware serial interfaces for communication with GSM/Ethernet/Bluethooth/Zigbee/GPS modules, JPEG CMOS cameras etc. (One serial port is used by onboard USB-to-Serial FT232BL chip to simplify device configuration, flashing and debugging procedures but USB functionality may be disabled by a jumper so there will be four serial ports at your service);
  • Dedicated I2C real time clock chip;
  • Dedicated I2C thermometer/thermostat chip;
  • Standard AVR ISP 10-pin connector for in-circuit flashing;
  • Standard JTAG 10-pin connector for in-circuit debugging;
  • USB connection via serial port emulation, Win/Linux driver support;
  • MicroSD slot for storing pictures, sounds etc;
  • I2C connector for interfacing with tilt/accelerometer/motion etc sensors;
  • Interface for 2×16 3.3V LCD display, backlight fading out feature;
  • Two buttons for toggling modes;
  • Three LEDs (green, red and blue) to indicate states, the first one is used for USB traffic indication, the last two could be programmed at designer discretion;
  • Two extension connectors with 10 and 6 I/O lines;
  • PWM driven interface to external speaker;
  • Four interfaces to external servo motors;
  • Pre-flashed bootloader allows to program the unit via USB, no need in external AVR ISP programmer;
  • Open source firmware unlocks literally unlimited potential of this unit;

Currently the project is underwent intensive firmware development phase and the source code is available to the community as open source project at DefendLineII at SourgeForge.net.

PCBs will became available for buying fully assembled, not assembled (just bare PCB) and with some critical components soldered to simplify assembling for less advanced hobbists and beginners.

DefendLineII blog articles:

Circuit Diagram;
Soldering Tips;
Flashing Bootloader;
Building Firmware;
Terminal Commands;
C328 JPEG Colour Camera Intergration;