Arduino Tutorial 51: DHT11 Temperature and Humidity Sensor with LCD Display
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- Опубликовано: 11 сен 2024
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In this lesson we are working towards a portable temperature and humidity sensor using the DHT11 sensor and an LCD display. In order to facilitate a more practical portable system, we are using an arduino nano, since it can be plugged directly into the breadboard.
You can get the kit I am using for this series at the following link:
amzn.to/2I7N4Ek
I strongly suggest picking up an arduino nano, since it can plug directly into the breadboard, making a portable system more practical. You can pick one up here:
amzn.to/2WXTC2M
As projects get more complicated in these lessons, you guys really need to get a set of breadboard jumper wires which allow you to make neater connections on the board in your projects. You can pick a pack of these wires up here:
amzn.to/2XrY5Kq
In addition as projects get more complicated, you are going to need a bigger breadboard. This is a reasonable one here:
amzn.to/2IY4d3M
Check out our WEB site:
toptechboy.com...
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#Arduino
This was a hard project for me because THIS beginner bought a clone without realizing it and had to figure out how to burn the bootloader on and hook the board up to the Uno directly (Master-Slave) because I couldn't get it recognized on the port! Fortunately, there are a TON of resources out there online that helped me figure it out. I'm so glad you did this build on the Nano because I need to learn to use those smaller boards (for my own art/jewelry projects) and I've been afraid to try them. Thanks for the push! ;)
Thanks for the tip! It put us on the right track. We also went and bought clones and got stuck in the same way. We solved it by reading your comment.
please give the resource you downloaded the file from, cant find any working one
Hahahahaaha. I usually use atmega stand alone for compatibility
I did it on my own on both the UNO and NANO! Thank you Paul for teaching it the way I guess nobody else will. Love from India!
I made one of these, and put it in a box. I powered it with a 12-volt cigarette lighter and a buck converter. I placed it on my bus so I can see the temperature of the cab. Now I would like to Pace another one in the back of the bus so I could see temperatures in the front in the back.
that's good, maybe you can just add another temperature and Humidity Sensor in the back and put it in the same arduino, and read both ,you can compare them and also see the difference if you want
Doing these projects gives me so much of joy including the immense learning that comes along. The most excellent channel indeed! Thank you Sir ❤️
I did this on my main board and will repeat it when my nano is delivered. Another top tutorial. I also did a bit of background work and added a degree symbol to the temperatures lcd.print((char)223) and rounded the values lcd.print(round(tempC). Thanks again Paul.
Thanks for the tip Keith! Believe this is what Paul mentioned by community working together.
As I only have an LCD with the I2C interface soldered onto it I had to figure out how to get that working before I tackled the DT11.
But I'm very happy to report that everything went very smoothly afterwards thanks to your excellent tuition.
Many thanks to you Paul for a very satisfying project/lesson.
yah me too and i was originally super confused abt why there's a chunk of electronics stuck to the bottom of the lcd lol
This project kept giving me issue after issue, and it was all because I was given a faulty kit! I'm doing this as an assignment for school and I've been practically tearing my hair out for the last three days trying to figure out what was wrong. The battery that came with the kit was dead and the sensor that came with the kit was broken. I got a new sensor from my dad and had a fresh battery on hand, but if I hadn't I would've been SOL. Your video definitely helped get me through the coding and wiring, so thanks Paul!!
I appreciate you recommending other items but making clear your projects are still completable using the kit. Also, did it by myself!
This was a great learning project, thank you. I did it the 1st time using my Uno R3 and a breadboard and got it working properly. I then used the ALL IN ONE SENSOR SHIELD V11 which took me a while to figure out the pin sequence between the LCD 1602 & the ALL IN ONE. I did manage to get it working perfect. Thanks for these amazing video's.
i am 4 years late to these but they are so helpful!! thank you so so much
I don’t have a nano YET but hooked the uno up with the power pcb with a 9volt battery and powered the arduino uno on the V in pin and GND. It all fits on the smaller breadboard. Also got a box of jumper. Makes it a LOT neater. Great tutorials Paul!
GREAT VIDS, ALL OF THEM. However my wife wants be to stop saying "BOOM!" and "Most Excellent" :)
Yes indeed! Boom!
@@rogerlilley4702 Most excellent Reply!
😂🤣😂😃
I too have adopted Most Excellent!
Wow. Took your advice and bought the Nano, short wires, and triple breadboard. Big change. I found a pair of needle nose pliers very helpful for placing the tiny jumpers. Another thing I wasted a LOT of time on but finally debugged it - worth mentioning if you have not already. The +ve (red) and -ve (blue) rails do NOT run the entire width of the bigger board. A channel divides them down the middle. For example the top rails runs from col. 0 to 29 and then 31 t0 60. There is a divider at col. 30 and the 2 sides HAVE TO BE JUMPERED. I had my LCD on the left and NANO on the right and could not figure out what was wrong! A little testing of the rails with a multimeter finally solved it. Now it works great.
Excellent!
Did this before I followed the lesson. Work with MEGA2560 - DHT11 and LCD-display with I2C-board. Due too my DHT-library I had to add the library "adafruit unified sensor".
Everything worked en I while follow all lessons because I am a beginner.
Thanks foor teaching us.
Nailed the hw in 10 min! These things we are building are starting too look more like something you'd buy at Home Depot. Plugged this to a battery....stuck it in the freezer and the temp dropped. Humidity increased to 90 blowing on it, and formatted the text perfectly on the LCD updating every 5 sec.
While i made cursor(0,0) static for humidity value displayed, i delayed cursor(0,1) to display TempC and Temp F. I see GROWTH. Thank you Paul.
Did the home work!!! I used a Nano 33 iot.... The LCD didnt work at first, I figured out that the Nano 33 did didn't have enough power to power the LCD, So I tried to hook up a 5V power supply. That worked.. And from there I saw on the diagram the Nano had a Vin pin and I said to my self.... "Fortune favors the bold" I held my breath and added jumped 5V to it. It works !!!!!
Did the homework! Added a variable to capture previous temperature and humidity to eliminate excessive LCD "Flicker" Only rewrites to the LCD when there is either a change of temperature or humidity from the previous read, 1-second prior. Powered by 9-volt battery, and/or 12-volt plug-in transformer.
I took your advice and got an Arduino nano, the breadboard jumped wires, and the bigger breadboard. The wiring is a lot neater.... And I've made it portable... Yes, the parts are all in there to do it. Another great lesson...
Nice work!
I did both, with the UNO i went portable and walked around, and the NANO got it to work thanks to your training.
I did this lesson on my own. My components came in and I used the Nano for the first time. I had to trouble some minor issues like loose wires. I made it portable already. I still watched your video because you gave me a new idea to power my ardouino with the power bank. Thank you for that.
"IT'S ALIVE" 😃. Had to burn a bootloader as I purchased a cheap Nano, used the power module and 9v battery out of kit.
Cleared the display after each print, so it alternates between Humidity%, Temp.C and Temp.F, and works great. Sense of achievement is off the scale.
Next step the MOON.
I did it using the Nano, and it was a bear getting it to work. The IDE seemed to be stuck on the UNO board. It was driving me nuts. There were all kinds of complex suggestions on the internet as to how to fix it. The one that worked was getting a new power cable (cheap here in Saigon). So now the Nano board was recognized and accepted. Next problem, also driving me nuts, was an error message when running the code. This I finally fixed by changing the processor setting to Atmega328P(old Bootloader). It was very satisfying once I got everything to work. Thanks again Paul for all you do.
Paul, I travel for a living and spend many, many weeks living out of a hotel room. So, I have time to go thru your lessons plus, Arduino and the associated parts and materials are very portable. With your fine instruction I am taking my electronics hobby to higher levels. You are a fine teacher and inspiring as well.
We head south for the winter in a motorhome, I too love the portability of the hobby.
I tried to sort of make up for the calculator homework I needed to get a hint or two from Tutorial 49. This time I did the homework for this Tutorial 51 a 100% on my own. I wish we had the option to share picture files on RUclips so we could show our work, but it's probably for the best, so that spammers can't come and disturb our peace and learning.🙂
Successful with the homework and with a bit of research I wrote in the 'degree' symbol for temp :-)
Bought a pack of Nano's, which came with unsoldered jumper pins and discovered my soldering iron has called it a day. So now waiting for another Amazon delivery! Then I go mobile!! :-)
I was following this lesson up to the point where Paul hooked up the Nano with its USB cable. It was then I realized that I did not get the Nano WITH a cable. Back to Amazon :( for a cable. I should get this tutorial done before I leave to visit my daughter, son-in-law, and my granddaughter for Christmas 2023. This means a week and one half away from the course. More to come on this post.
I love his energy about his successful project when he screams like a child and say, Boom. Geddy Up. Such a great mentor to me. Today, is difficult to wire all those stuffs. It is really difficult to debug if wires up one after another. I guess, it is time to come big board to hook Paul 's next project. Hope for the best in future project. Thank you very much to give us your wonderful content again. God bless you.
Completely did not notice you leaving out "int" s in your variable setups. Completely did catch the comma you left out in the lcd setup. I did get the Nano and used it for this lesson (did it before watching) and had one wire off which rendered it non-functional until I discovered my mistake. Went on to do the homework, finding the power supply and hooking it up for power. already using the big new breadboard. Another great lesson, thanks!
Worked through the process with Paul. Good outcome. After mangling a number of the small jumpers on my breadboard, I used the fine point of my multimeter to pre-open the correct holes on the board. Worked well and it takes a little longer to plug them in, but they go in easier and are still secure.
Thank you once again. I did purchase an Arduino Nano but I am having difficulty getting it recognized. I went ahead and completed the assignment with the Mega I have been using for the previous projects and I got it working quickly and correctly - very satisfying! I see in the comments below that getting the Nano recognized is a common problem so I will do more research and get that figured out. I was just too impatient to get to the next lesson to bother with the Nano but I will have it working correctly soon. Thank you, Steve.
The Nano...so darn cute stuff. Got this working really nicely and added an LED to tell me when the temp reading took place every 8 seconds. The NAN problem is also solved. Salute to Paul.
Present. I did the homework, but I still watched you build it, good for the RUclips algorithm. I have watched every video all the way through so far. I did not use the nano, but I did utilize the new jumper wires you prescribed. Planning on getting the nano before too long.
BOOM!! It worked first time! just had to play with the way the info was displayed. Totally enjoyed this lesson!
Great to hear!
I'm really enjoying the lessons. I'll admit to going a bit off-piste with the homework. Did it with my SSD1306 display instead.
As a slight aside I decided to learn actual C++ to help with the coding. I feel like I've developed a super power just because I now know that I can go into the library and look at the functions in side it find out what it can do. Added on a Heat Index to my display because I found it in the DHT library!
I'm starting to realize that most of the problems I'm having are hardware related. I bought a DHT22 heat sensor and all my readings are correct now. Life is good
I had my circuit built and working using the UNO board. I thought that was our last homework assignment. Fortunately that freed me up to wiring in the NANO board. All of it went fairly smoothly. now it time to move on to portability. I suspect it involves the 9 volt battery. Time for a little research. Thanks for sharing your knowledge Paul.
Got a nano and neat short wires and combined info in lesson 50 and 48 to do this on my own. So chuffed with myself. Attached a cheap powerbank to the usb cable to the nano and walked round the house checking temperature (I prefer in degrees C) and humidity. All my wires extra neat, I'm sure that I'm more OCD than you Paul.... Thank you again for making such wonderful lessons - I really look forward to learning the next thing.
Paul, I made it completely portable with the nano, the design wires and a power bank! I discovered that the current was too low for my bank to keep functioning, so I had to add 2 LED's to the circuit, just to keep my bank providing, otherwise it drops after 10 seconds. I think diminishing current is also the reason why I can't load my cellphone a 100% when hiking in the woods. Thanks a lot for this great tutorial, it's a giant leap forward and opens some doors of perception ;-) Greetings from Belgium!
Such a good teacher, I didn't even need to follow along to make it work! Proud to say I did it all on my own! I did use a MEGA2560 and long cables but ordered some Nanos, short jumper wires and more breadboards whilst you were talking. Sorry I wasn't paying attention, Sir!
I am thrilled to find these tutorials. My background is programming and I just love your approach. I am retired and just having a ball playing with these Arduino lessons. Huge thank you for all the effort you put in to these videos.
This project was a lot of fun! Thank you, was able to stop the video after your physical connection portion and write the code based on what you taught before. Great class.
Great job!
I did it on my own! It's an amazing feeling making things work. I have a different kit, working with different hardware and has to research read stuff to make it work especially with the LCD I have with an I2C. Most amazing feeling tinkering on things and making it work! Thank you so much, Paul!
Got mine working perfectly using the Uno as homework, but enjoying binge-watching the lessons so much that I've just splurged on Amazon with more breadboards, wires and a Nano :-D
Hey, you did it! And close to how I did it! Good for you!😉 Seriously, Paul. Thank you for putting these lessons out there, I just wanted to wire up a Boeing 737 throttle quadrant and it's switches and maybe a MCP panel, but now in addition to that, I'm kinda hooked on going through all these Arduino lessons and checking out all your other micro controller classes as well. Thank you!
I did the homework on my own with my new arduino nano and new prototype board under an hour!
However, my temperature readings were in Celsius because I live in Canada :)
Thanks for the detailed instructions. I am new at coding, but I was able to follow along. Everything seem to work fine using the serial monitor. When I connected the LCD and added the codes for it, the temperature and humidity were off by about 20C and 14% respectively...….and seem to work negatively, that is to say, when the sensor is exposed to increasing temp, it would actually decrease the values and vice-versa (I am currently in a room at 20C and 23% humidity, LCD is showing -0.5C at 8.8%). No changes were made to hardware or wiring. The only thing that was changed was the additional coding for the display. I would appreciate any feedback. Thank you for the most excellent teachings.
I got it going with my Nano !!!
Thank you Paul !!
I included Celcius and a 9V batterie with 5v power supply.
Finally did my first homework with no hiccups... Usually need to see follow up lesson to correct my errors. Did with the Uno... Nano comes in the mail tomorrow 😎.. looking forward to taking everything to the next level... Thank you again Paul ... Watching these 3 years after production... saw on Pauls Live Stream that the Pico W is going to be the next adventure... Hope to be done with this series over the next few weeks and gearing up for the new episodes !!!!!!
Great job! I am really excited about the upcoming Pico-W class. I will really try my best on that!
Sir, I did the assignment myself. I'm still waiting for the kit but I manage to keep up with your lessons. Thank you very much.
Can someone explain where the USB on the nano is from. I ordered the nano and hadn't got it with it
@@abdihogsade47 i just saw this now, you may have already figured it out but i think you can also replace it with any usb cable that has the same size as the plug.
We did it without your help by looking at our code for #48 and #50. Worked like a charm!
My NANO turned out to be an Elegoo 3 so had to install drivers for it, but after that all went smoothly. I 3d printed a tray which takes 2x bread borads and a slot for the battery, hooked it all up with the psu board from the kit. Booom! fully mobile. Please keep up the great tutorials.
Boom!
Hi Paul, very interesting tutorial. Whenever you retake this one I would suggest you include three things: 1/ when switching from uno to nano make sure you have the right driver for the nano installed; 2/ when buying a nano make sure you get a cable for the nano with it because the cable for the uno does not work with the nano and last but not least 3/ since the cable that comes with the nano is very short, get some ISB extensions to that you can continue to work on your desk rather than on the floor of your desktop... These maybe minor oversights but if they are not highlighted in the introduction of this tutorial they can cause people to loose a lot of time.
Thanks Paul. Appreciate your vids. Initially impressed with your "under the hood" explanations of LEDs and logic gates. Was hoping for one on LCD.
Listening to you talk through the build of the circuit sounds very familiar. With all the circuits of varying sorts that I have built over the years, I have verbally walked my way through the connections as a double-check of my work.
Again a great example of how important it is to methodically check your work as you go along. Like yours, mind worked first time I applied power. Causing a real feeling of accomplishment. Thanks, Paul, for the superb lesson.
Happy to reach the 51st video ! & So excited to do the rest ! Thanks a lot !
Enjoy!
Homework completed! I'm still working with the regular Uno board and the long jumper wires for now, but it helps to know what equipment I should be getting when I'm ready to start expanding.
BOOM!
I can see the benefit of using a nano, but I couldn't wait and did the homework using the Mega2560 and plugged the 9V battery to it. Most excellent!
Either I am learning something from your lessons, or my ability to cut and paste your previous lessons together and make them work is improving.
Got this one before you even showed your coffee mug!
to be really honest, I did the homework and if I check I did the same way as you do, then I just play your video at twice speed while doing math. Since I can't support your patreon, I will just do this.
Hey! I did it with the Elegoo. I needed this for my college experiment. Wasn't able to figure out to do it with the LCD, but after following your series I have learnt so much and able to understand everything. Thank you so much!! You've worked so hard! 😀
Great job!
did it with UNO, ordered NANO - waiting for it. Thank you, Paul!
We built this with the nano and the uno. We have a couple of various component boxes. It was interesting to see how the temperatures vary between them. Thanks for the great video.
Sorted !!
I still had the LCD display hooked up on the breadboard so just had to include the code to write to it.
Also got myself a few more Eleego breadboards which I can clip together and a Nano.
Hooked it all up, downloaded, connected a power supply and hey, I can now unplug from my PC and walk about with it. Cool. I'm already seeing some potential here in building test devices for use with my commercial software. Great stuff, as usual. Will try and post a video at the weekend.
Apologies if these points have already been covered but if I missed them others may also have done so.
1. My sensor was reading high so I found it could be calibrated with the line
float tempC = HT.readTemperature() - 1.7; (The sensor was 1.7 C too high)
2. Anybody buying Elegoo Nano boards will find the pins need soldering (new stuff for me) and the driver downloading. On testing my solder joints I found pins A6 and A7 didn't work and it took some searching to discover that they have no output capability on these boards.
Hope this helps somebody.
Loved this project!👍
Still watching, making it all the way to the end, getting anxious to do some builds and coding believe I'm learning enough that my project reason for being here will come to life! Increasing confidence, difficult for an old learner to do.
Hey Paul, I did do this project on my own as an extension of the previous lesson just to challenge myself. I have 3 DHT11 sensors, so what I wanted to do is i wanted to set them all up to see how different the readings would be. So reporting back, the max observed difference between three of them atm is 1.7C, which is within the accuracy of 2C from the manufacturer's data sheet. The max observed difference in humidity is 1%, which is also within the range of 5% allowed variance.
Didn't get the Nano yet, but I have the "cool" wires ordered, so I can neat up my board. I also have two more 183 pin breadboard, so I am thinking about just getting a piece of plywood and sticking all three of them next to each other on that plywood. I think it could work and give me some extension in regard to the real estate to play with. I am trying to control myself really hard here not to buy every little thing I find on amazon, as I already did go crazy and got myself several kits - elegoo mega 2560 kit, elegoo r3 kit, Upgraded Electronics kit (that one has "neat" wires) and 37 sensors kit. Then I got a multimeter and usb tester, set of pliers and a wire stripper. Now I am sitting, looking at all of this and thinking - oh dude, did I overdo it?.. Again?.. 😂
By the way, nice lesson, as always!
Just curious, if you averaged all the sensor readings, would that be more accurate?
@@matthewcollins1858 It should be more accurate than one sensor alone if they are located in the same general area because each sensor has a bit of imprecision, either plus or minus. So the more readings you average, the more precise the average should be. Unless the sensors are all consistently over-calculating or under-calculating, then your average would be wrong.
I used a Arduino Micro for this and a 20 X 4 green LCD display and I did this as the homework so sadly I didn't follow along : ( but I still watched the video. Thank you for your hard work, this was a long one!
Jumper wire tip: If you have old solid copper phone line wire it can be used to make custom length jumper wires. Phone wire is 22 - 24 gauge wire and fits perfectly into breadboard sockets.
PAUL: I thank you so much from heart for all these videos!!!!!!!
Please continue this Arduino series!!!
I'm not a online course learner , but honestly your tutorials are so great that I have so much motivation to learn more and more every single day with your videos. High efficient videos , keep up your excellent Work Paul
Glad you like them!
Easily did this one on my own. A lot of fun and learning through doing things on my own!
I love it when a project gets to the point of NOT relying on the USB cable. Good job. BUT, I will continue to use a I2C interface to eliminate all of those display wires.
I bought a nano, and made it myself … thanks for the lessons
BOOM!!! Managed to build & code the whole thing on my own from previous lessons.
For my homework from the last lesson, I got the portable unit built using an Arduino Nano, the DHT11, and an I2C Serial 16x2 LCD display.
i use a nano too, but i bought this very early one cause my goal is to make a wireless RC car. great video.
I did the home work and it worked the first time 🙂
This was a super easy project for me as I have been using arduino nano since the beginning.
I AM LEGEND! And I added a little bit extra! So, I thought it would be cool to see in both Fahrenheit and in Celsius So, I put a push-button and it switches from Fahrenheit to Celsius!! Thanks Paul so much!
Legend!
Hello Paul, my name is Mario.
Before the lesson I had allready done it but still with the wires of the kit, because my smal wires and the nano is still on the way.
The build looks crazy but works fine.
Thanks for sharing your lessons! I enjoy em and learn a bootload of things ;-)
Yes Sire!!!!!
I did do it all along with you but i did use Arduino Uno and I2C lcd display which made it easy!!
thank you ...Happy Teachers Day (belated).
I took a different approach and left the Humidity to show first then the Temperature in F. But I did not include the serial.print in program as I'm trying to be on the LCD only. Thank you Paul for your fine teaching. By the way, I came up with my on programming on this for the first time! I just looked at the programming in the lesson and developed it as best I could.
Great lesson. Yes I did get working with the UNO then I transferred everything to the NANO, it bombed. Checked the connection several times no go, replaced the pot still no go. Wrote the program to output to the serial monitor, Hey Presto works great. I have a bad LCD, evidently I jacked up my LCD, ordered a new one, but all in all I like this setup better, it's smaller and easier to walk around with. Thanks Paul.
I did not buy a NANO, I might sometime. I did do it the same way you did, which was good. Thank you Paul for a great lesson.
Thanks Paul. Another great project. Used a nano and it works well!
Thank you for these nice tutorials. They are addictive! I'm learning a lot and having so much fun.
On this last one I noticed that the "%" sign for the humidity didn't show up on the LCD display because of the 16 characters limitation. Since the humidity comes out in discrete steps, I changed it from FLOAT to INT and now the % shows up.
Hello Paul. I bought a kit and some sensors online and this was my first project with an LCD display. Your channel is very useful !
I was assembling the stuff with you but had to take a detour because in the kit the LCD came with an IC2, much less wiring.
I also hooked up a TMP36 that came in the box.
The DHT11 reads 25.30 C and the TMP36 reads 20.80 C.
Well at least it wokrs. I'm gonna see other projects in your channel!
Yep, did this homework on my own prior to this. Still good to see your methodology. Great Vid. This un-tethering concept makes sense. I designed and 3d printed my own project board which holds the Arduino + breadboard firmly in place together. Nano in the post though. Phil (UK)
BOOM!
Did it with Mega2560, few mistakes but learning all the time, great series of tutorials for me as a complete novice, keep them coming.
I used the Nano on a Prototyp PCB Board with the old school wire wrapping style and it works like a charm.
I love these cool projects. Thank you very much Paul, you rock! ;-)
Did it myself. I used the large board and the UNO, I added a LED that turns on for 200 Ms every cycle just to show that it is working.
Excellent Lesson. Worked really well and used the power bank to make it portable. Looking forward to the next one. Many thanks
Another "Most excellent" tutorial. I had some issues getting it to work but refused fold up like a cheap lawn chair. I worked it out eventually :)
Excellent!
I did this homework assignment and it worked!! I was skeptic on this one. Great lesson!
Thank you for suggesting to use the hookup wire kit. I had one laying around but have used up most of the parts; however, I noticed that internal strands of the CAT5, CAT 6 EitherNet wire is AWG 22 and has thinner insulation. You can using a AWG 22 stripper to clean the ends. Makes a nice looking breadboard. Every time I watch your video's I learn something. Thanks for sharing your knowledge.
Another great lesson ! The homework for this week is done. My solution works with a 9V-Batterie.
In Germany actually on my windowsill outside we have 7 degrees Celsius and 56 % humidity.
12/16/23 - the cable arrived. I made the changes to the IDE. 1/ Tools | Board set to Nano. 2/ Tools | Port COM3. Ran the DHT test and it passed. Loaded 50DHT11-LCD.txt and it ran fine connected to the USB port. Mounted the power supply and it ran untethered on a 9v battery. That was the assignment.
Thanks, Paul! Great lesson, I don't think any people get bored when you explain and carefully connect wires between the pins, it's engaging )))
Arduino Nano looks great, I ordered myself a pair and also extra bread boards & neat wires to be able to do several projects at once :)