nandannaveen
Posts: 7
Joined: Thu Aug 20, 2015 5:56 am

Temperature and moisture sensor for Raspberry pi 2

Mon Sep 14, 2015 12:07 pm

Heyy guys i have got temperature and humidity sensor

http://www.amazon.in/DHT11-temperature- ... B00BOMEO5U


got moisture sensor

http://www.digibay.in/soil-dust-humidit ... ure-sensor

and LCD display

http://www.amazon.in/JCE-16x2-LCD-Display/dp/B00OVY28M4


I need to make automated Plant care system connected to windows IOT App, does this peripheral works ?

scotty101
Posts: 3649
Joined: Fri Jun 08, 2012 6:03 pm

Re: Temperature and moisture sensor for Raspberry pi 2

Mon Sep 14, 2015 12:24 pm

I don't think the LCD will work. It states 5v and doesn't mention anything about being 3.3v compatible.

There are plenty of raspberry pi compatible LCDs available that do work.
Electronic and Computer Engineer
Pi Interests: Home Automation, IOT, Python and Tkinter

Massi
Posts: 1691
Joined: Fri May 02, 2014 1:52 pm
Location: Italy

Re: Temperature and moisture sensor for Raspberry pi 2

Mon Sep 14, 2015 12:33 pm

nandannaveen wrote:Heyy guys i have got temperature and humidity sensor
http://www.amazon.in/DHT11-temperature- ... B00BOMEO5U
This is a very common DHT sensor.
Since readings from this sensor has to be very timing precise, i'm quite curious if it's possible to have it working on win10 iot.
On raspbian it is all working using precise timing of interrupts, is this possible on IOT?
This is purely analog. You need an adc to use this on your raspberry.
Well, is this a HD44780 display? In this case, it shouldn't be much pain to get it working..
I need to make automated Plant care system connected to windows IOT App, does this peripheral works ?
With standard raspbian this would be almost trivial. I think with IOT we are still in the age of "try and see" :)

ricl
Posts: 657
Joined: Wed Aug 26, 2015 11:55 am

Re: Temperature and moisture sensor for Raspberry pi 2

Mon Sep 14, 2015 1:36 pm

I would go with an I2C temperature/moisture connected device, which should then be very easy to use in a IoT application.

https://shop.pimoroni.com/products/spar ... AgdI8P8HAQ

HDMI is the only supported display option on IoT (for now).
ricl : F/gamma = ma : Law ii(a) : https://climatedatablog.wordpress.com/2016/01/02/an-energy-challenge-2016/ #AnEnergyChallenge2016

haroldpulcher
Posts: 58
Joined: Tue Jun 09, 2015 8:08 pm
Contact: Website

Re: Temperature and moisture sensor for Raspberry pi 2

Mon Sep 14, 2015 3:40 pm

I would suggest a using an I2C device as well. WinIoT directly supports that protocol and it is way easy to use.

Not knowing any of your size constraints, I would suggest something like: https://www.sparkfun.com/products/11931


Massi
Posts: 1691
Joined: Fri May 02, 2014 1:52 pm
Location: Italy

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 8:26 am

i'm going a little off topic, but from the answers (everyone is suggesting to use an i2c sensor), can i suppose that with win10IOT at the moment it's not possible to precisely time interrupts? (precisely time: get in the callback for each interrupt the system tick that interrupt occurred)

ricl
Posts: 657
Joined: Wed Aug 26, 2015 11:55 am

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 10:18 am

IoT is not a real time OS so, at the end of the day, no matter how much you make a thread high priority, background, no UI, etc. you still cannot absolutely guarantee that it will run continuously without possibly being suspended for a short time occasionally in a difficult to debug way. (With 4 cores, how long that will take will depend on what else you have going on).

This is a multi-tasking UI OS and other threads, including the OS, can always push their way in regardless.

Windows CE is still the Microsoft real time OS, not IoT.
ricl : F/gamma = ma : Law ii(a) : https://climatedatablog.wordpress.com/2016/01/02/an-energy-challenge-2016/ #AnEnergyChallenge2016

Massi
Posts: 1691
Joined: Fri May 02, 2014 1:52 pm
Location: Italy

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 10:25 am

ricl wrote:IoT is not a real time OS so, at the end of the day, no matter how much you make a thread high priority, background, no UI, etc. you still cannot absolutely guarantee that it will run continuously without possibly being suspended for a short time occasionally in a difficult to debug way. (With 4 cores, how long that will take will depend on what else you have going on).

This is a multi-tasking UI OS and other threads, including the OS, can always push their way in regardless.

Windows CE is still the Microsoft real time OS, not IoT.
ok, now i'm entering my noob modality :)
is this in any way different from raspbian behaviour? afaik, no.
But on raspbian get the precise tick of an interrupt is trivial.

Note: this is the farest post from a "os war" you can imagine. I'm looking forward to test IOT myself, but i've got some sensors that _needs_ precise timing to decode messages. i can't get rid of this.
Even to decode signals (like ir signals) i need to give ticks to interrupts.

ricl
Posts: 657
Joined: Wed Aug 26, 2015 11:55 am

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 11:42 am

On IoT, device drivers are used to insulate the OS from the hardware/outside world. Effectively they turn hardware interrupts into buffered software ones.

If you want to add to the device drivers on the Pi, then it is possible, but fairly non-trivial.

Using that code to very precisely time and sample external data in a 'guaranteed to run, never, ever interrupted itself' sort of way is not going to happen though.
ricl : F/gamma = ma : Law ii(a) : https://climatedatablog.wordpress.com/2016/01/02/an-energy-challenge-2016/ #AnEnergyChallenge2016

Massi
Posts: 1691
Joined: Fri May 02, 2014 1:52 pm
Location: Italy

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 12:40 pm

ricl wrote:On IoT, device drivers are used to insulate the OS from the hardware/outside world. Effectively they turn hardware interrupts into buffered software ones.

If you want to add to the device drivers on the Pi, then it is possible, but fairly non-trivial.

Using that code to very precisely time and sample external data in a 'guaranteed to run, never, ever interrupted itself' sort of way is not going to happen though.
thanks a lot for clarification.
Going on with my noobness, isn't this something usable?

https://msdn.microsoft.com/en-us/librar ... s.85).aspx

thanks :)

ricl
Posts: 657
Joined: Wed Aug 26, 2015 11:55 am

Re: Temperature and moisture sensor for Raspberry pi 2

Tue Sep 15, 2015 2:59 pm

Nope.

You can only write User Mode drivers, not Kernel Mode drivers (which need to be signed by Microsoft to install on IoT).
ricl : F/gamma = ma : Law ii(a) : https://climatedatablog.wordpress.com/2016/01/02/an-energy-challenge-2016/ #AnEnergyChallenge2016

Massi
Posts: 1691
Joined: Fri May 02, 2014 1:52 pm
Location: Italy

Re: Temperature and moisture sensor for Raspberry pi 2

Wed Sep 16, 2015 8:46 am

ricl wrote:Nope.

You can only write User Mode drivers, not Kernel Mode drivers (which need to be signed by Microsoft to install on IoT).
thanks again.
to me, this is a huge limit (not the user/kernel drivers management, the lack of precise timing for interrupts :))

Return to “Windows 10 for IoT”