- Joined
- Mar 26, 2018
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Hi All,
Thought some of you might enjoy this. Wife and I have 3 cats but often end up traveling out of state for work and holidays. We have a neighbor stop in to feed them, but we are always worried about our kitties! Rather than constantly text her to see if she stopped by, or install a camera (kinda creepy?), I figured I could put my micro-controller and programming skills to work.
I used a magnetic reed door switch to sense when the door is open. The switch is tied to a digital input on a NodeMCU Wifi enabled micro controller. These are around $3 on Amazon and are quite powerful for a basic micro.
I programmed it in the Arduino IDE and used a web service called Blynk to create an iPhone app that displays the data I want. My project was simple enough that I could just use the free features within Blynk.
Here is the simple app I built (yes... I know my phone is almost dead). It creates a push notification (ding!) whenever the door opens, time stamps it with an accurate RTC reading, displays an on screen LED to tell me if the door is open, has a button to clear the history, has a big display for when the door was last opened, and a 10 line table to show the time the door was opened as well as the duration of the visit and how long between visits. I might change the big display to show an incrementing time since the last visit.
Maybe 5 hours of work and $15 of hardware needed ($10 of which was a USB cable from Home Depot ) to get this to work. I have programmed Arduino compatible micro-controllers for years now, but always thought that web interfaces were out of my reach.
The machining part of this will be a simple case for the micro-controller and a better mount to stick the magnet on the door.
Mike
Thought some of you might enjoy this. Wife and I have 3 cats but often end up traveling out of state for work and holidays. We have a neighbor stop in to feed them, but we are always worried about our kitties! Rather than constantly text her to see if she stopped by, or install a camera (kinda creepy?), I figured I could put my micro-controller and programming skills to work.
I used a magnetic reed door switch to sense when the door is open. The switch is tied to a digital input on a NodeMCU Wifi enabled micro controller. These are around $3 on Amazon and are quite powerful for a basic micro.
I programmed it in the Arduino IDE and used a web service called Blynk to create an iPhone app that displays the data I want. My project was simple enough that I could just use the free features within Blynk.
Here is the simple app I built (yes... I know my phone is almost dead). It creates a push notification (ding!) whenever the door opens, time stamps it with an accurate RTC reading, displays an on screen LED to tell me if the door is open, has a button to clear the history, has a big display for when the door was last opened, and a 10 line table to show the time the door was opened as well as the duration of the visit and how long between visits. I might change the big display to show an incrementing time since the last visit.
Maybe 5 hours of work and $15 of hardware needed ($10 of which was a USB cable from Home Depot ) to get this to work. I have programmed Arduino compatible micro-controllers for years now, but always thought that web interfaces were out of my reach.
The machining part of this will be a simple case for the micro-controller and a better mount to stick the magnet on the door.
Mike