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.
Little Wire is multi-featured USB controlled Open Source Hardware tool packed in a minimal form factor designed by Ihsan Kehribar.
This is an unassembled kit and requires basic soldering. This is designed for use with the Digispark development board, which is not included.
|Temperature Sensor Shield PCB||1|
|DS18B20 1-wire Temperature Sensor||1|
|3.5 mm pitch 3-pin screw terminal||1|
|4.7k ohm 1/4W 5% resistor||1||Brown - Black - Yellow|
|0.1“ pitch Jumper/Shunt||1|
|1x40pin male 0.1” pitch header||12 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 the the DS18B20 Temperature Sensor, matching the shape of it with the printing on the board and solder all pins.
Insert resistor. Solder the leads and clip off the excess.
Cut a length of male headers 3 pins long and insert into the jumper location (labeled P1 DAT P5). Solder the pins on the back.
Place the jumper/shunt on top of the pins just soldered. Position it over DAT and P5 or DAT and P1 based on whether you'd like to use P1 or P5 to communicate with the sensor.
Insert the 3-pin screw terminal with the hookup openings facing outward. Solder the two pins.
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.
External 1-wire devices can be added to the same 1-wire bus by connecting them to the 3 pin screw terminal - following the labeled pin outs on the board.
Sensors other than the DS18B20 will not be covered in the included examples, but many examples are readily available online.
With the newest version of the Digispark Arduino IDE goto Examples→OneWire→Digispark Example
This example uses P5 by default - to use P1 change this line: OneWire ds(5); to OneWire ds(1);