Using Wemos D1 Mini & Oled Shield

Category : Arduino, Electronics

In this guide I’ll show you how to use the shield and it’s two buttons. Lets get to it.

Resoltion is 64×48
Button A is by default pin D3.
Button B is by default pin D4.

Buttons can be customized by soldering jumper pads under the shield.


Wemos D1 Mini @ Aliexpress

Oled Shield @ Aliexpress

PS, be sure to get the shield with A & B buttons when you buy it, there are a few types to choose from.


There are several libraries to choose from, but I found the one from Sparkfun to be suitable for my use.

Download it, then unzip in libraries folder and restart Arduino IDE. Then paste my code:

#include <Wire.h>  // Include Wire if you're using I2C
#include <SFE_MicroOLED.h>  // Include the SFE_MicroOLED library
#define PIN_RESET 255  //
#define DC_JUMPER 0  // I2C Addres: 0 - 0x3C, 1 - 0x3D
MicroOLED oled(PIN_RESET, DC_JUMPER); // Example I2C declaration
void setup()
  // Before you can start using the OLED, call begin() to init
  // all of the pins and configure the OLED.
  // clear(ALL) will clear out the OLED's graphic memory.
  // clear(PAGE) will clear the Arduino's display buffer.
  oled.clear(ALL);  // Clear the display's memory (gets rid of artifacts)
  pinMode(D4, INPUT); // Setting D4 B Button as input
  pinMode(D3, INPUT); // Setting D3 A Button as input
void loop()
  oled.clear(PAGE);     // Clear the screen
  oled.setFontType(0);  // Set font to type 0
  oled.setCursor(0, 0); // Set cursor to top-left
  oled.print("Line 1");
  oled.setCursor(0, 8); // Set cursor to top-left
  oled.print("Line 2");
  oled.setCursor(0, 16); // Set cursor to top-left
  oled.print("Line 3");
  oled.setCursor(0, 24); // Set cursor to top-left
  oled.print("Line 4");
  oled.setCursor(0, 32); // Set cursor to top-left
  oled.print("Line 5");
  oled.setCursor(0, 40); // Set cursor to top-left
  oled.print("Line 6");
  if (digitalRead(D4) == LOW)
    oled.setCursor(0, 40); // Set cursor to top-left
    oled.print("B Pushed");
  if (digitalRead(D3) == LOW)
    oled.setCursor(0, 32); // Set cursor to top-left
    oled.print("A Pushed");

You should now see this when buttons are pressed:

Thats it! Now play around with it. Hope this short guide was helpful.

Using Wemos D1 Mini with SHT30 Sensor Shield

Category : Arduino, Electronics

SHT30 is a temperature and humidity sensor, almost the same as DHT22 only much smaller. They also measure a larger range, from -40 to 125 C.


What we need is a Wemos D1 Mini board, which can be found on Aliexpress for around 5$. And of course the SHT30 shield can also be found on Aliexpress for a few dollars.

SHT30 @ Aliexpress

Wemos D1 Mini @ Aliexpress


Next up is installing the Arduino Library for the SHT30, unzip in libraries folder and restart Arduino IDE.

Then in Arduino IDE select the example called SHT30_SHIELD, or use example code below,  just to verify that our sensor is working correctly.

#include <WEMOS_SHT3X.h>
SHT3X sht30(0x45);
void setup() {
void loop() {
    Serial.print("Temperature in Celsius : ");
    Serial.print("Temperature in Fahrenheit : ");
    Serial.print("Relative Humidity : ");

Then open up the serial monitor and you should see it reporting temperature and humidity:

Thats it! Now play around with it. Hope this short guide was helpful.

My Makerfarm Prusa i3v 10″

Category : 3D Printers, Electronics

Thought I write a quick review of my Makerfarm Prusa i3v 10″.


Of all my printers this is the one I’m most satisfied with, mainly because of it’s large build area and speed. It’s also easy to modify.

I’ve changed a few thing on it, to improve the quality and speed:

Wider spool holder


The on that came with it wouldn’t fit all my different rolls of filament, so I printed out this part from thingiverse. Basicly just makes it hold wider spools, fit’s perfectly. Make sure you print it will high infill rate, I used 80%.

Aluminium heat bed mount & isolation


I used a thin sheet of glava isolation which greatly reduce heatup times, and a aluminium bed mount. The bed mount makes it more rigid as large wood sheets tend to flex. You can find glava or similar rock/glass isolation at your local hardware store. Makerfarm sells the aluminium bed upgrades. Click here to get it.

Astrosyn stepper motor dampers


Not so easy to see in this picture, but it’s impressive how quiet it became after I mounted these to my X and Y axis motors. Haven’t bothered to install dampers to my Z axis motors yet, since they aren’t running all the time while printing.

I also added washers to all my screws holding the motors in-place, this reduces pressure on the wood pieces. Not sure if this is necessary but I felt the small screw head was drilling it’s way into it.

These are the dampers for Nema 17 steppers. Since Astrosyn does’t normally ship to Norway I had to contact them and arrange a deal.

E3D V6 with 0.5mm nozzle

IMG_2968 IMG_2966

This one is a major improvement! Faster print speeds and better quality. My main bottleneck now is the extruder mechanism, when running at extremely high speeds it will slip. I had to cut the extruder fan shroud to make it fit on the e3d, but apart from that it’s a easy installation.

You also need to modify your firmware, I got mine from makerfarm with E3D support added. You can download it here.

Wanhao Duplicator i3 mods I’ve done

Category : Electronics


I’ve had my Wanhao i3 for a few months now, and I must say it’s not perfect. I wasn’t expecting a perfect printer either.

But there are a few very annoying issues that needs to be fixed IMO, even tho many users have had no big complaints. My major struggle on this one are uneven bed adjustments. I can have a perfect print, and the next time I print it screws up at the first layer. It’s almost like I have to re adjust for each print.

You might be thinking that this is my first printer and I’m just not used to this, but I have been using 3d printers since early last year and now own 6 printers. And my latest in the collection is the Wanhao i3, and I feel I’m quite familiar with bed leveling. Not claiming to be an expert.

Anyhow, these are the mods I have done so far:

Heatbed isolation.

This can be done several ways, but I choose a rather quick fix for it. Simply cutting a cork mat I bought off ebay, and taping it to the underside of my heatbed with kapton tape. This helps on heating up the bed faster, and makes for a more evenly distributed heat pattern.

MicroSD to SD card adapter.

Easy fix, you can find one here. I used some adhesive tape to keep it locked in place on top of the electronics box.

LED lights.
ledextruder ledtio

Many ways to do this one, but I used a pair of led strips with adhesive tape on them, and a 1W led emitter on the extruder. Just make sure you order some 12v ones.

Z-Axis stiffening.
screwdetail2 screwdetail

Link to all parts are on this post on thingiverse. As you can see on the first picture I have added two threaded rods and stiffens my Z-Axis. This mod I would really recommend, makes the whole printer much more rigid, resulting in higher quality prints.

After you have attached the threaded rods and nuts, you need to use some angling tool to make it perfect 90 degrees.

There are other useful parts in that post too. And I also recommend printing the front and back Y brace. And adding a ziptie to make the bed belt go more evenly.


This summons up all mods I’ve done to my i3 so far. It’s still not as good or reliable as I want it to be, but it’s much better.I’m far from done, my next mod will be a replacement of the hotend part with a all metal one from Swiss Made. It will be interesting to see how it performs with that one installed.

Cheap eBay brushless gimbals?

Category : Electronics, RC

It’s really exciting how much the prices have dropped on brushless gimbal lately, and there are swarming with 70$ gimbals for gopro on ebay. I’ve seen some videos around youtube about their performance and it seems pretty good!

So I got around and ordered me one for testing, turns out it worked fine out of the box:

Great! I sold that gimbal to a friend and ordred me a new one, why not? They are working out of the box. Only mount your gopro camera onto it and power it on! So I thought.

My second gimbal arrived in a different box, and after closer inspection it has a different layout on the PCB, it also has a micro usb instead of a mini usb. So what, I mounted my gopro and powered it up. Heres my results:

Listen closely, can you hear that cracking noise?

After several rounds of testing, I still get the same results. So I contacted my eBay seller and complained about it. Long story short, he is now sending me a new controller board. He also provided me with some manuals written in chinglish. They might come in handy, especially if you also are having trouble with one of these gimbals:

Dropbox link for manuals.

Guide: Flashing Hobbywing Skywalker 20A ESC with BLHeli Firmware

Category : Arduino, Electronics, RC

This guide will tell you step by step how to flash a Hobbywing 20A esc with BLHeli firmware for multirotors. It will be the same procedure for any other ESC with a silabs chip, you just need to find the pin-outs for it. Well lets get started.

You will need the following:

Arduino (UNO, Nano etc. I use a Mega 1280 in this guide)
Three wires (I used some male to female jumper wires)
Soldering-iron with a tiny tip
OlliW`s flash-toolkit

Step 1:

Attach your selected Arduino board to your computers USB and run the following file from the OlliW toolkit “AvrBurnTool_vxxx.exe”. Choose the type of Arduino board and select it’s COMport, then click the button “Burn All”. This will burn the flashing-tool onto your Arduino board, you can use your Arduino board for other sketches later, this will not make your board useless for other tasks.

A CMD window will popup and let you know the flashing is in progress and then done. Just close the AvrBurn tool and the CMD window. Lets move onto next step!

Step 2.

Remove the plastic wrapping around your ESC, and get familiar with the soldering points as show in the next picture (click on the picture to see a larger one).


Now solder on the three jumper wires onto the pads shown in the picture above. The GND can be very tricky to solder, but after some try and fail I noticed it doesn’t need to be soldered exactly where the picture shows, but you can use the GND(black) at the servo-cable connection. Or generally any other GND. The red and white are easier, just put some tin on them first, then while you heat the wire, attach it!

It should look something like the picture below.


Then we attach the three wires onto the Arduino boards ISCP header, as shown in the picture below.

Step 3.

We are now almost ready to flash the ESC, but before we do so the ESC needs a lipo battery connected. Needs to be powered on while flashing. The start the file  “BLHeliTool_v100.exe” and choose your ESC make, model, type. As shown in the picture below.


Or choose the firmware file directly “BLHeliHexFiles\SKYWALKER_20A_MULTI_REV9_3.HEX “, and hit Flash!

If everything went smooth it should say “Flash hex file… DONE!” 🙂 To verify this click the “Setup Basic” tab and select READ, this will tell you the firmware type.


PS! At the moment 9_3 firmware will cause “twitches” when used on the Skywalkers, a new fix is in the works. And will be released in a matter of days.

UPDATE: v10 firmware is now available, check out this link.


X525 V3 ARF from Goodluckbuy

Category : Electronics, RC

I just took the next step and ordered a real quadcopter, it is a ARF kit thats based on the x525 frame. The contents of the kit looks okay, and I guess for a first time build it’s just a good thing most parts already has been selected for me.

Kit Contents:

– X525 V3 folding frame*1
– KKMulticopter v5.5 *1
– XXD 2212 KV1000 brushless motor*4
– 3.17mm Shaft adapter*4
– GEMFAN Carbon Nylon 90×50″ 9050 9050R CW CCW Propeller *4
– Hobbywing 20A ESC*4
– ESC Connect Board*1
– Heat shink tube*12
– Not assembled,just a kit

I will most likely not be using the KKMulticopter 5.5 board, instead I have a KK2 from Hobbyking on it’s way. It looks much easier for a newbie to understand and setup. As some extras to the kit I also got a few extra props, one screw set, prop savers. I also ordered one extra frame kit!

The receiver I’m gonna use is the Turnigy 9x, and for powering this quad I will be using the lipos listed under here. Of course I will not use both at the same time, but I thought I’d give it a shot with different C ratings and mAh:

I’ll try to update this blog with a build log.


Review: The three cheapest video cameras found on eBay

Category : Electronics

First of all this review has nothing to do with my previous blog post about the 808 #16 camera as I haven’t got mine yet.

So, lets introduce our three tiny video cameras.

Mini DV 808 Car Key Chain

Price is typically around 6-8 USD, this little key chain camera has nothing to do with the real #16, except they use the same plastic housing. Video quality isn’t great, it’s blurry and hard to see any details if there are movements. The camera also struggles if the brightness changes, etc going from indoors to outdoors. Or pointing the camera towards a window. The bottom line is, don’t buy it! You will be better off with the real 808, even if it costs a bit more. This camera weighs 13,9 grams with the metal key-hook removed.

Mini DV MD80

Price for this camera generally lays around 8-11 USD, it comes with allot of different mounts. The general quality feel of the housing is good, you get the impression it’s more well built than the other cameras in this test. Video quality is decent, it’s the best from these three cameras I’ve tested so far. Weight of the camera is 19,4 grams.

5MP Smallest Mini DV

This is the most expensive camera in this review, it’s priced from around 11-16 USD, in video quality it’s better than the 808-clone, and not as good as the MD80. Even tho the resolution on the recordings are high, but the compression makes it blurry and not all that good. One thing I noticed this camera cuts the recording into several files, highly annoying! The weight for the camera is 15 grams.


There we go, three of the cheapest eBay mini dv`s tested! I’ll add a video soon, showing the quality of each camera.

Mini DV 808 #16 – Key Chain Camera

Category : Electronics, RC

A long time ago I bought a small key chain camera from a random eBay shop, I knew the video quality had to be very bad considering it’s size, and I was right. But then I stumbled over a thread on RC group discussing just something similar to what I had bought. In fact it was identically looking, only the internals was better on the product discussed on rc groups.

I soon discovered I had bought a cheap china copy of a not so cheap china product hehe. The real hd key chain camera would record 720p in a decent quality.

So me and a friend went onto eBay to look for this #16 model, a real one that is. We found a great deal only 40$ including shipping for each 808. So I’m gonna do a quick review when mine arrives in mail. Until then, here is a sample video someone else recorded with the 808.


  • 1/4” CMOS WXGA HD Sensor / H.264/AVC1 DSP / Hynix 512M DDR2
  • Rechargeable LIPO Battery (250mah), with Battery Charger Manage IC
  • Video: 720P HD H.264/AVC1 video codec, 1280 x 720 30fps .mov
  • Photo: JPG 1280*960 (no degrading by upsizing to interpolated “5 megapixel” size)
  • microSD card slot, supports up to 32GB
  • USB2.0, plug and play, easy connection with computers, no driver needed.
  • Super mini size, only around 50mm (L) x 32mm (W) x13mm (H)
  • Super light-weighted: only approx 17g!
  • Multifunctioned, you can use it as a mini DVR, a camera, a webcam, a removable USB drive.

Stay tuned!

Bad quality shield bought on eBay

Category : Arduino, Electronics

I was looking for some cheap shields for my Arduino board, and stumbled across a very inexpensive proto shield. A well known seller with good reputation had it laying around for only 7,65 $, so it couldn’t be that bad.

Well, after a couple of weeks it arrived in the mail. And here are a few things I noticed:

Looks like it’s rusted and kind of old?

Not even close to nice solderings…

Some plastic is melted off? 😛

Well, its not worth that much and it actually works, but for how long?

Whats most annoying is how the seller can say that its Quality and New!