Little Wire

Little Wire is multi-featured USB controlled open source hardware tool packed in a minimal form factor designed by ihsan Kehribar. Even though it has minimal form factor, and packed with full of features; there aren’t any SMT components involved, therefore it is very suitable for beginners to assemble. 
This tool has to take instructions at run-time over USB. It can't work in a computer-less environment.
V1.1 beta firmware released for the Little Wire. You can find the changelog and details from this link.
  • USB controlled multi-tool with:
    • 4-channel digital input / output
    • ADC (10 bit resolution)
    • 2 parallel hardware PWM outputs  
    • SPI interface
    • I2C interface
  • USBtiny compatible AVR programmer
  • Printf style debugging over AVR-ISP pins
  • USB to UART converter (alternative firmware -- CDC-232 port)
  • Onboard serial bootloader for firmware upgrades 
  • Minimal form factor and all through-hole components
  • Open Source Hardware design
  • AVR programming /summon captainObvious 
  • LED dimming, color mixing  
  • General servo driving   
  • Pan and tilt servo control of a webcam for face tracking
  • With additional motor driver IC, 2 wheel robot driving   
  • Analog voltage recording and plotting
  • Controlling LED matrix displays by using SPI module to drive shift registers
  • USB to SPI bridge
  • USB to I2C bridge
  • USB to UART bridge
  • General purpose V-USB developement board
Packing list
  • 1 x Little Wire PCB
  • 1 x Pre-programmed Attiny85 chip.
  • 1 x 8pin IC socket
  • 1 x USB Male Type A connector
  • 2 x 3.6v zener diode
  • 2 x 100 nF capacitor
  • 2 x 27 Ohm resistor
  • 1 x 1.2 kOhm resistor
  • 1 x 150 ohm resitor
  • 1 x LED ( for power indication)
  • 1 x 2pin male header
  • 1 x 2pin jumper
  • 1 x (2x3)pin male header
Silkscreen AVR-ISP PWM/Servo ADC I2C SPI CDC-232 Bootloader
pin1 MISO Channel_B - - DO TX TX
pin2 SCK - Channel_1 SCL SCK RX  
pin3 RESET - Channel_0* - CS -  
pin4 MOSI Channel_A - SDA DI - RX
Analog functionality on pin3 pin isn't stable but supported. Use it at your own risk.
Document Links
What is included?
  • Eagle schematic / layout files. Also in PDF format.
  • Microcontroller firmware files and makefile  
  • Bootloader source files
  • C function/header files for command line USB interface for Windows and Linux
  • C++ class for Windows and Linux 
  • Processing library for Windows ( With reduced feature set ... ) 
  • C# class for Windows USB interface ( in development ... )
  • Example C projects for almost every feature of the board
  • Example C++ projects for almost every feature of the board  
  • Example Processing projects
  • Example C# project for analog voltage plotting based on zedGraph