Beagle Board -

BeagleBone Black project spotlight:
Open Sprinkler Beagle (OSBo)

By Tara Stratton

Planning to buy a sprinkler timer for your loved ones this holiday season? Have no fear, OpenSprinkler is here! Developed by Ray Wang at Rayshobby LLC, OpenSprinkler Beagle—nicknamed OSBo—was released last week. It is an open-source sprinkler/irrigation extension board for the Sitara-processor-based BeagleBone Black. The board helps you easily develop BeagleBone Black into a low-cost, web-connected smart sprinkler controller. It comes with a full-featured sprinkler scheduling program, uses online weather data to help regulate water time, and enables users to remotely change setting and programs while away from home. It works with the standard 24VAC sprinkler valves commonly found in household watering and irrigation systems and allows for an unlimited number of water zones to be individually controlled. Because it’s open source, it offers a lot of flexibility in features and functionality. Users are encouraged to hack the hardware and/or software (written in Python, which is easy to learn).

What motivated Ray to create such an innovative and futuristic project? Ray wanted to provide a solution to the limited set of fixed functionality and outdated user interface that come with most commercial sprinkler timers or controllers. Ray even included a relay on OSBo and hopes it can be used for opening/closing garage doors as well at some point in the future!

Ray has made several other versions of OpenSprinkler based on other low-cost computers, but he selected BeagleBone Black for the newest version to add even more features thanks to the large number of GPIO pins, built-in analog pins, eMMC, microSD card, and the high-performance Sitara AM335x processor from TI. The OSBo board contains a 24VAC to 5VDC switching regulator, shift register, triacs, terminal blocks, a zone expansion board connector, a rain sensor terminal, and a mini-relay. It provides 5V power to BeagleBone Black and uses four GPIO pins to interface with the shift register as well as SDA2/SCL2 to interface with the DS1307 RTC. The BeagleBone Black computer is oriented face-down, and it plugs directly into the extra-long male pin headers. The biggest advantage of the face-down design is doesn’t necessitate cables, thus there is extra space in the upper-half of the enclosure that makes it possible to add additional modules. To make it easy to reuse the available pins on BeagleBone Black, Ray also mapped out all of the 46 pins on ports P8 and P9 to the pinout area.

Check out the OSBo homepage at for more information or to purchase the OSBO v1 open-source sprinkler / irrigation extension board. You can also stay up to date on what Ray is developing on his blog at

Last updated by on Tue Nov 19 2013 20:41:05 GMT-0000 (UTC).