Jeff McKelvey author of SoCGadget, created his own garage door monitoring system using XBee in his Issaquah, Washington home.
Jeff documented his design, Low Power XBee Module, on SoCGadget. After reading the post, iDigi’s own Jordan Husney, author of the article 12,000-Mile Universal Remote published in the Smarter Homes edition of Make Magazine, gave Jeff a suggestion that improved his design.
Jordan suggested the “deep sleep” mode that uses the sleep_req pin and external logic to wake the XBee in order to send a sample. The changes give near instantaneous feedback when Jeff’s door is open or closed and allow him to run his design off of a pair of modest AA batteries for six months or more; versus only a few weeks when he was using cyclic sleep.
Check out the result, Jeff’s improved design, documented here.
“In a previous blog post, I created an XBee digital input device to monitor the state of my garage door. Since there was no convenient power source where I needed the sensor, I designed it to be battery powered. I also wanted the battery to last long enough that I wouldn’t get irritated by replacing it all the time. The results weren’t bad, I had a device than ran about 3 months, in practice, from the 2000mAH LiPo battery pack I was using. However, an individual named Jordan Husney commented on that blog with an idea to make it better. I finally got a chance to go with the idea and the results were well worth the trouble.
The new design leverages XBee’s pin sleep mode and some external hardware that wakes up the XBee to send data samples only when the state of the garage door changes. This means the XBee is in a low power deep sleep mode most of the time, saving considerable battery power.”
Jeff, a software engineer by profession, started SoCGadget to share information about micro-controllers and system-on-a-chip based projects.
Congrats to Jeff on his project and thank you for sharing on SoCGadget.
Are you automating your home? Creating things with XBee? Let us know! You can see more XBee projects in our XBee Project Gallery.