Little Wire & Digispark
Recently, I came across details regarding the Little Wire for Digispark Shield Kit, which simplifies the utilization of Digispark as a Little Wire device equipped with the Little Wire firmware and libraries. Little Wire, created by Ihsan Kehribar, is a compact open-source hardware tool with a multitude of features that can be controlled via USB. I’m pleased to note that Digistump has begun offering shield kits to enhance the ease of using Digispark with the Little Wire firmware.
Little Wire for Digispark Shield Kit
The Little Wire for Digispark Shield Kit, designed to be used with the Digispark development board, is an unassembled kit that requires basic soldering skills. Once you’ve successfully assembled the kit, you can proceed to load the necessary firmware as outlined below:
• Download the Little Wire firmware installer for your OS platform at http://littlewire.cc/downloads.html (under “Single click installers for v1.3 firmware”)
• Run the execution, and when prompted, plug in the Digispark that you will be using with the finished shield kit. Watch the command window to proceed (see screenshots given below).
Thereafter, Digispark becomes a Little Wire device about five seconds after it’s plugged into your computer.
For my Windows 7 (x64) PC, I downloaded the needed Windows Driver (64 bit) located under the “Binaries” section of the downloads page (http://littlewire.cc/downloads.html).
It’s important to emphasize that the Little Wire firmware does not supersede the Digispark software; rather, it’s a program that’s uploaded in a manner similar to an Arduino sketch. As such, you have the flexibility to replace it with an Arduino sketch using the standard upload procedure whenever necessary.
An Alternative!
If you can’t readily access its shield kit, you still have the option to create your own shield using a small perforated circuit board or a Digispark protoboard. The original shield offers the convenience of jumper-enabled pull-ups for the I2C lines, along with an external VCC jumper, and these features are also included in the schematic provided here.
Additionally, if you believe it would be beneficial to connect the Digispark protoboard with a DIP-8 socket for programming your Attiny85s, you can accomplish this without too much difficulty. Simply solder the IC socket and establish connections by linking six wires from it to the AVR ISP header in the correct sequence. That’s all there is to it!
For the curious, here is the pin assignment of Attiny85. Keep an eye on the four connections: MOSI, MISO, SCK, and RESET (don’t forget that you need to wire up VCC and GND for the IC socket).
