Hardware to generate event on Open/Closed circuit?

[kkl]

I'm looking for any hardware options to trigger an Event when a circuit Opens or Closes (Continuity / No Continuity). I believe this is called a Digital Input (0 voltage). A +12V/0V DC input would also work for me. I think that the Velleman K8055N with plug-in would work, but I don't want to overlook other inexpensive options. Thanks for any leads.

[krambriw]

If you eventually would have a wireless receiver like the RFXtrx this type of module could be an alternative:

WBT-912.png (85.75 KiB) Viewed 2771 times

Otherwise, a RaspberryPi with it's inputs (GPIO) is most likely the cheapest. Install Node-RED that supports tons of things, install a MQTT broker like Mosquitto and you can integrate it with EG

[krambriw]

...and not to forget...the 1wire technology

A controller

download.jpg (2.06 KiB) Viewed 2768 times

and an input/output module

See this thread: http://eventghost.net/forum/viewtopic.p ... it=onewire

[kgschlosser]

You also have the arduino end of things. these are full micro controllers, minicomputers that you program to do open and close circuits, read voltages. a whole plethora of things. and they are very inexpensive. 5-20 dollars and you can add things to them called "shields" that add functionality like wifi, ethernet, bluetooth, cellular data, gps, figerprint sensors, LED's, pretty much anything you can think of.


as an example. i used a magnetic reed switch that i put into my doorbell right next to the electro magnet. and i connected it to an arduino so that the arduino can see if the reed switch is open or closed and if it closes (someone rang my doorbell) the arduino sends an event via wifi to my eventghost computer.

there is a guy on the forums named pearbear i believe is his handle that has made a library for the arduino called etherevents specifically tasked with communicating with eventghost. taking most of the guesswork out of getting it running. there is a learning curve with the arduinos as you have to create and flash the firmware on them. but is a very simple thing to do and the sky is the limit with them.

another example i have running. i use an arduino to output voltage to a wire and that wire if stuck into the soil next to my foundation on my house and i have another wire that is put into the soil from the arduino as well. right next to it. and on that wire i have it read voltage. and based on how much electricity is passing between the wires i know how damp the soil is and if my basement is flooding or not. this is really nice to know because I have a finished basement and live in the mountains where basement water happens. so i know if it is or isn't going to flood if the moisture content of the dirt starts to rise and i have it trigger an event which starts an action to send a text message to my phone letting me know.

very useful.

if you are interested i would be more then happy to help you learn using one of these devices. they are cheap and if you believe it's to difficult it wasn't a huge waste of money.

basically between 5 and 10 dollars for the controller and some time.

and pearbear as well i know would help you out

[kkl]

Thanks very much for those ideas. The great thing is that you've already written EG plug-ins for them. Thanks!

There's one other intriguing option I stumbled across. PoKeys makes these neat devices with a huge number of I/O ports. The PoKeys57U has 55 digital inputs, 7 analog inputs, and many more features. The software appears to be robust. $69 USD, 42,00 Ôé¼

[kgschlosser]

that's pretty spendy. it's a micro controller just like the arduino. and the atmega 2560 has 16 analog input pins, 54 digital input 15 of which can be used for pwm, 4 serial ports, and it supports spi and i2c for communications. last time i bought one it was 12 dollars. WiFi for it is about 2 dollars and Ethernet is 8. the Ethernet comes with an sdcard slot as well. the atmega chips are used in most vehicle Body Control Modules. cool thing is though they will run on anywhere from 5 volts to 20 volts dc

[kkl]

Arduino and Raspberry Pi are both devices that I've wanted to learn, just never had a good enough reason or enough knowledge. I had no idea that the atmega 2560 had that many I/O ports. I may take you up on your offer to teach me some basics. Thanks!

[kgschlosser]

The pi is very different than the arduino. And the arduino excells at high speed asynchronous data. Like controlling addressable LEDs or as an ir transmitter/receiver. This is because there is no operating system to interrupt the processor from doing what you want it to do. And also if they lose power abruptly there isn't the chance of having an operating system get corrupted. I have and run both but only out of necessity because to run my ambilight there isn't a means that is already made to go from media portal to arduino. I have to use hyperion which runs on the pi. But all the new LEDs are only a data wire no clock. And the raspberry has issues handling the asynchronous data. So I have the pi send the data to the arduino which controls the LEDs. Way to many pieces involved and I have to reboot the pi all the time for dropping connections. But that is where EG steps in. So I just have EG reboot the thing every time my projector turns on. And since the projector takes a while to warm up they pretty much finish at the same time.

But the arduino can pretty much handle every aspect of home automation I have them controlling my fireplaces. Sump pumps in my basement. All the ir blasting and receiving.