WEMO Hardware

Showing results for 
Search instead for 
Do you mean 
Reply
WEMO Maker Inventor
Posts: 6
Registered: ‎06-21-2014

Re: Available Sensors

As far as I can tell, the sensor input is just a TTL-compatible logic input, with an internal 4.7Kohm pull-up resistor to +5V. So logic "0" would be 0V to 0.8V, and logic "1" would be >=2.4V. I don't think there's an A-to-D in the wemo maker. Nice as that would be. Would be nice if the wemo folk could publish more electrical data on the device.

WEMO Maker Inventor
Posts: 8
Registered: ‎05-17-2014

Re: Available Sensors

Just received my Maker today and I'm already lovin' it.  

 

I've got quite a few sensors that I use for arduino that I'll be using....PIR, Ping, etc...

 

As well as integrating it with arduino as well for further logic.

WEMO Maker Inventor
Posts: 4
Registered: ‎07-28-2014

Re: Available Sensors


adchan wrote:

As far as I can tell, the sensor input is just a TTL-compatible logic input, with an internal 4.7Kohm pull-up resistor to +5V. So logic "0" would be 0V to 0.8V, and logic "1" would be >=2.4V. I don't think there's an A-to-D in the wemo maker. Nice as that would be. Would be nice if the wemo folk could publish more electrical data on the device.


   No, at http://www.belkin.com/us/wemo-maker/, it clearly states "Once connected, the WeMo Maker allows you to monitor a variety of 5v analog sensors."

 

   This indicates that the sensor port is analog, not digital. The emphasis is mine. Smiley Happy

 

   I will be exploring this more tomorrow.

 

   8-Dale

WEMO
Posts: 8
Registered: ‎05-13-2014

Re: Available Sensors

Most of the 5v sensors available for the Arduino will work for the WeMo Maker.
WEMO Maker Inventor
Posts: 6
Registered: ‎06-21-2014

Re: Available Sensors

I wish that was the case (sensor being an analog port). The brief info released by WeMo to-date can lead to that conclusion. I, too, first thought that the Sensor input has an internal A-to-D connected to it from their description. Having played with the Maker a bit, I am now convinced that it's just a logic input pin.
WEMO Maker Inventor
Posts: 45
Registered: ‎07-31-2014

Re: Available Sensors

Yes so to help clear things up the sensor used must have a GPIO (General Purpose Input/Output) type interfaces. Here's a good tutorial to help explain this...

 

GPIO - Wiki

 

If that doesn't help visual what type of sensors that can be used another way to look at it is from the point of view of a PLC (programmable logic controller such as Allen Bradley or Siemens. Normally you use ladder logic to create "programs" using various inputs and outputs to obtain what you want. The ladder "step" is a line of various combinations of NO (Normally Open) and/or NC (Normally closed) contacts (or sensors in our case) and a device at the end to represent what your energizing. I know this might confusing so here is a tutorial.

 

PLC Programming Tutorial

 

Which brings up another point currently the WeMo app has a limitation on the complexity of IF statements that can be programmed in it. At the moment only a simple logic statement such as this can be programmed…

 

If "Sensor" is "high"   turn "light" "On"   --- (where each item in quotes can be modified.)

 

At the moment complex statements such as the following can't be programmed with the WeMo app...

 

If "Sensor 1" and "Sensor 2" are "high" turn on "Light 1" and "Light 2"

 

Going back to PLC logic the above more complex if statement could be hard wired to accomplish a hardwired equivalent to AND, OR, etc. I'll post a topic later to explain this with some examples later on. (Another alternative is to use IFTTT to create more complex statements although at the moment the WeMo Maker can't be used by IFTTT but it's in the works apparently. Another issue with IFTTT is there can be substantial delay in executing statements so be careful.)

 

 

 

Eric

_________________________________________
http://community.wemo.is/t5/Discuss-WeMo-Maker/How-to-guide-for-testing-the-WeMo-Maker-without-sensors-attached/m-p/1852#U1852
http://community.wemo.is/t5/Discuss-WeMo-Maker/Sensor-Fix-Options-for-converting-an-active-high-circuit-to-an/m-p/2522#U2522

Connect on LinkedIn: https://www.linkedin.com/in/ericmadej
WEMO Maker Inventor
Posts: 11
Registered: ‎06-16-2014

Re: Available Sensors

I've got my WeMo Maker all setup and ready to go... and ordered the PIR Motion Sendor (https://www.adafruit.com/products/189), it should be here tomorrow and then I can really start playing.

 

I was wanting to try out my unit with my Smartthings and IFTTT, but saddened to see the integration is not ready for either. For now I will stick to the IF rules in the WeMo app.

 

I'm thinking I'll use the motion sensor to turn on my other WeMo lights in the house when it senses motion in the garage, and use the WeMo maker relay as my garage opener. Nice way to tie in to be able to open and close from my phone. (I already have a Smartthings sensor monitoring if the garage door is opened or closed.)

WEMO Maker Inventor
Posts: 11
Registered: ‎06-16-2014

Re: Available Sensors

Anybody have any luck getting a PIR Motion Sendor (https://www.adafruit.com/products/189), to work with the Maker? I got mine today but apparently I'm having a hard time figuring out which wire goes where... I've tried what I think is right, and then tried every other configuration but I can't get the Maker to trigger with the sensor. I've even tried following their tutorial page (https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/), but maybe I am missing something... or need something else to get it to work.

 

I'd appreciate any input anyone has.

WEMO
Posts: 11
Registered: ‎09-03-2014

Re: Available Sensors

Hello Inventors,

 

         There was a typo on the website.

 

Sensor Input:

 

  1. 4.7k Pull up to 5VDC.
  2. This is a standard TTL input, normally High in the untriggered state.
  3. Pulling this pin low, to gnd, triggers the GPIO.
  4. This is not an analog input

Hope this helps Smiley Happy

 

Jason

WEMO Maker Inventor
Posts: 103
Registered: ‎07-29-2014

Re: Available Sensors

Totally guessing here, but you may have to bypass the regulator. The website indicates you can run in with 3V if you do that.

 

From the Adafruit page:

"Runs on 5V-16V power (if you need to run it off of 3V you can do that by bypassing the regulator, but that means doing a bit of soldering)."

-G