ESP32 Starterkit

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ESP32 Starterkit met alle onderdelen verkrijgbaar !!! Scroll omlaag voor de uitleg.

Christmass is coming up and that is the time for presents.
If you are looking for a present for a loved one, friend, or family member that wants to start with Home automation, electronics or the ESP chips in general consider my book on the ESP32 which has all ingredients to get someone starting. 

For a full list of chapters look here:
http://lucstechblog.blogspot.com/2020/06/esp32-simplified-my-book-in-english-now.html

For an international list of resellers look here:
http://lucstechblog.blogspot.com/2020/10/esp32-simplified-world-wide-available.html

Next week is Christmass and the week after is New Year so this was the last posting of this year.

Have a Merry Christmass and a Happy New Year.
Lets hope it will be a lot better then this one.
Stay Safe !!!

Luc Volders

 

 

 

 

ESP32 Starterkit

Het is bijna Kerstmis en tijd voor cadeautjes.

Als je iemand in de familie of vriendenkring hebt die geinterresseerd is in electronica, huisautomatisering of de ESP32 chip in zijn algemeenheid dan is er nu het ideale Kerstcadeau.

De firma Otronic https://www.otronic.nl/ heeft een complete starterskit beschikbaar voor de ESP32.

Naast De ESP32 zelf worden alle onderdelen bijgeleverd zoals breadboard, jumper kabels, weerstanden, leds en sensors zoals ze in mijn boek staan beschreven. En uiteraard is mijn boek in het Nederlands ook bijgeleverd. De kit heet niet voor niets: ESP32 Starterkit Luc Volders editie !

Hier is de lijst met alle bijgeleverde onderdelen:

1x    Boek ESP32 Uitgelegd 365 pagina's van Luc Volders
1x    ESP32 Development Board
2x    Breadboard 400 gaats
100x    Weerstanden diverse waardes
50x    Transparante LEDs in 10 kleuren
10x    Dupont Jumper kabel 20cm M/M
10x    Duppnt Jumper kabel 20cm M/F
1x    Dallas DS18B20 thermometer
2x    LDR
1x    SG90 Servo motor
1x    TIP120 Power Transistor
1x    UBS Breadboard power supply
1x    Relais 5v
2x    DC Motor 5v
2x    470µF Condensator
1x    8 Leds RGB WS2812 strip
1x    L293D motor driver chip
1x    PIR sensor 5v
1x    RCWL-0516 magnetron radar sensor
1x    SW-18010P trilsensor
1x    SW-520D tilt sensor
1x    Display TM1637 4-digits rood
1x    Mini OLED dispay 0,96 inch I2C 128x64
1x    Schuifweerstand
1x    Micro USB kabeltje
1x    5V - 3A adapter

Kortom compleet om direct met mijn boek aan de slag te gaan en de projecten en voorbeelden die er in staan te realiseren en natuurlijk zelf te gaan experimenteren.

Een fantastisch initiatief waar ik natuurlijk erg trots op ben.

De kit is te koop bij Otronic die overigens nog veel meer sensors en onderdelen beschikbaar heeft: https://www.otronic.nl/

Natuurlijk is het boek ook los te koop bij Otronic, Boekenbestellen, Kiwi Electronics, je favoriete lokale boekhandel of Bol.

Volgende week is Kerst, en de week erna Nieuwjaar dus dit is de laatste post van dit jaar.

Fijne Kerst en Gelukkig Nieuwjaar.
En laten we ervoor zorgen dat het nieuwe jaar beter wordt dan dit jaar.
Blijf Gezond !!!

Luc Volders

ESP32 Wifi-Analogread problem

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I was experiencing a strange error. And I could not find what I was doing wrong.

Short situation sketch.

I had an LDR attached with a 10K pull-down resistor to a pin of my ESP32 and I was going to send the sensors data over Wifi.

However the analog reading just gave 4095 all the time. So I presumed a faulty LDR. I exchanged it to a new one but no avail. I checked the connections over and over and still no result. The output of the ESP kept telling me the measured value was 4095.

Well then there could be only one conclusion. The analog input pin of the ESP32 should be defective. So I attached the LDR to another pin and presto: immediate result.

But something was nagging me. I had used that pin all the time when I was writing my book. So why would it suddenly be faulty. Therefore I started testeing other analog input pins and guess what:  some where working OK others were dead.

Wifi and Analog read do not mix on all pins !!!

Then I started digging in the technical literature and on the internet and then I found it. The ESP32 has two ADC converters ADC1 with 8 channels that are connected to GPIO 32 till 39 and ADC2 which has 10 channels. The problem is that ADC2 is used to manage wifi functions. So if you use Wifi you can not use ADC2 !!!

So the bottom line is: if you are using Wifi you can only use GPIO32 till GPIO39.

My Doit Dev Kit has not all of these pins exposed so I can only use GPIO32, GPIO33, GPIO34, GPIO35, GPIO36 and GPIO38. And testing revealed that these indeed worked as they should.



Above is a pin layout of the ESP32 Doit Devkit board with the Analog input pins exposed. You can use all these pins when you are not using wifi.

If you need Analog pins and Wifi only use the next pins:

pin D33 ADC5  GPIO33 OK
pin D32 ADC4  GPIO32 OK
pin D35 ADC7  GPIO35 OK
Pin D34 ADC6  GPIO34 OK
pin D39 ADC3  GPIO39 OK
pin D36 ADC0  GPIO36 OK

It is annoying but in the end I was just pleased that my ESP32 was not broken.

Till next time
Have fun

Luc Volders

SVG to STL

For an index to all my stories click this text.

Sometimes you need/want to print something easy. A 2D design which you want to use as a keychain or an anchor you want to transfer to a coat hanger.

There are two examples on this weblog. I made a location sign which you can find here:
http://lucstechblog.blogspot.com/2019/04/always-knowing-where-you-are.html

And I took a 2D design and altered into a coat hanger. You can find that story here.

To make a 3D print from a 2D design you need to do 2 important steps. Most pictures are in JPG format so you need to trasform that to an STL file.

The way I was normally doing that was by first transferring the JPG to an SVG file with convertio: https://convertio.co/nl/jpg-svg/

The next step was to convert the SVG file to an STL file using Tinkercad.
This works just fine and in Tinkercad you can adjust the size of the object before you convert it to STL.
The drawback is that you need an account for Tinkercad and that the process is slow (logging in, opening a new projact, loading the SVG).

So I did a quick search in Google and found an online SVG to STL converter. You can find it here: http://svg2stl.com/

SVG to STL

The website is simple and does what it needs to do.



Start with uploading an SVG file.



I tried uploading a JPG file. It was accepted however there were many artifacts shown. So that does not work.



An SVG file came out very well. So I converted it to an STL file.



It looked ok on the screen.



You can turn it in any direction you like for inspection just like the most STL viewers let you. After inspection just download it.



And here is the downloaded file in my slicer. And yes: for quick and dirty work I am using the creality slicer which is an old version of Cura but works just fine for most of my prints.

The slicer allows me to adjust the X, Y and Z dimension of anly loaded model so what I previous did in Tinkercad I can do now quicker.

JPG to STL direct ??

There are some websites that allow direct conversion from JPG to STL. I tried several of these and never got a good result. There is however another option to achieve this. That is for another upcoming story.

Till next time
have fun,


Luc Volders