This is an old revision of the document!
The Little Wire on Digispark Shield Kit connects provides a Little Wire compatible pinout on the Digispark. This allows the Digispark to be easily used as a Little Wire device, with the Little Wire firmware and libraries. The shield also provide pull-ups for the I2C lines, which can be enabled by an included jumper, and an external power jumper. The kit also includes a 6 pin IDC cable for connecting to other circuits or to standard 6-pin AVR ISP headers for programming AVR chips.
Little Wire is multi-featured USB controlled Open Source Hardware tool packed in a minimal form factor designed by Ihsan Kehribar. The Little Wire for Digispark shield was designed by Ihsan in collaboration with Digistump. Little Wire appears as a usbtinyisp device and provides a tethered interface between hardware and a computer.
Little Wire has the following features:
This is an unassembled kit and requires basic soldering. This is designed for use with the Digispark development board, which is not included.
|Little Wire Shield PCB||1|
|6-pin IDC Cable||1|
|4.7k ohm 1/4W 5% resistor||2||Brown - Black - Yellow|
|0.1“ pitch Jumper/Shunt||2|
|1x40pin male 0.1” pitch header||22 pins worth|
Soldering: If you are new to soldering we recommend the following tutorials: Soldering Basics (http://www.sparkfun.com/tutorials/106) and Soldering Crash Course from the folks at Sparkfun (http://www.sparkfun.com/tutorials/354). How to solder from the Curious Inventor: http://store.curiousinventor.com/guides/How_to_Solder
Adafruit has this excellent guide that starts with the tools needed and then shows detailed pictures, including some of the common problems that beginners experience (http://learn.adafruit.com/adafruit-guide-excellent-soldering).
We assume for these assembly instructions that you know the basics of thru-hole soldering. If you don't check out the links above, these boards are very easy to solder - we promise!
Empty kit bag (or if using a raw PCB, acquire parts) and verify contents. Note for Kickstarter Backers and Pre-orders: Headers are not included in each kit bag, but the entire order came with more than enough headers for all kits.
Insert resistors. Solder the leads and clip off the excess.
Cut two lengths of male headers 3 pins long and insert (from the top) into the 6 pin (2×3 pins) header. Solder the pins on the back.
Cut a two lengths of male headers 2 pins long and insert (from the top) into the two jumper locations. Solder the pins on the back.
Place the jumper/shunt on top of each set of pins just soldered. Optional: Placing the jumper on the I2C pins connects the I2C pull-ups (remove if not using I2C). Placing one on the Ext. Power pins connects the 5V lien to the 6 pin header (remove if using external power).
If using the cable - plug into 6 pin header.
Cut a length of male headers 6 pins long and one 3 pins long. Insert into corresponding positions (on the bottom of the board) and solder each pin.
Tip: Inseting the headers into a breadboard and then placing the board on top can make this process easier.
Note: If you are using stackable headers, use them here instead of the standard male headers.
Download the Little Wire firmware installer for your platform here:
Run the executable and when prompted plug in the Digispark that you will be using with the shield. When complete the Digispark will now appear as a Little Wire device 5 seconds after it is plugged into the computer.
See http://littlewire.cc for documentation, libraries, and more!