Arduino Simulator

Arduino Simulator

We had stumbled across an Arduino simulator, in which you can use both electronics and you Arduino skills to be able to test your circuit before buying the necessary component or just to prevent you having a fried Arduino.

It’s free and works really great, although it has one major downside, the sketches have to be saved in .hex files then imported into the simulator but other than that it’s a really great app to have. Once you get the hang of creating the hex files it is actually not too bad and it becomes quite effortless.



Here is a simple explanation on how to use Simulide.

First, you will have to download and extract the entire archive to your desired folder. If you run the executable from within the archive some functions will not be available. After extraction process has completed you can run the executable (.exe).

Next, build your circuit, remember to adjust the resistor values, on the left click on Properties and double click on the resistance value.



After you have built your circuit you can compile your sketch into a HEX file. In your Arduino IDE make sure your sketch is saved then go to Sketch->Export compiled Binary, or press Ctrl->Alt->S.

Now it’s time to load your sketch into the simulator, Right-click on the Arduino and select “Load firmware” and load your HEX flie you just exported, there will be two HEX files “xx.ino.standard.hex” and “xx.ino.with_bootloader.standard.hex” you have to select the one without the bootloader.

You are all set now and you can click on the power button at the top.

Another great Feature

The probe is another great feature the app has. Put the probe on up to four of your output pins and right click on it and select add to plotter.

Please note that this might look like an oscilloscope but it is a logic analyzer and will not work with PWM signals, for PWM signals select “Add to Oscope” instead of “Add to plotter”

Creating a Printed Circuit Board From a Diagram

Creating a Printed Circuit Board From a Diagram

Converting a circuit diagram to a Printed Circuit Board (PCB) could prove to be a challenging task.


But luckily with technology today it is fairly simple to complete this task, so there’s no need to be stressed out. We will be doing an easy one for today. It is called an A-Stable Multi Vibrator.

First, I will explain the circuit and the working thereof. Imagine that R2 were absent from the circuit, and suppose Q1 started out being turned on. Then Q2 would have nothing to turn it on, and Q1 would be held on by current through R3, while the R4 and the LED would charge C2. The effect would be that LED1 would come on and stay on, while LED2 would never light.

Now add R2. This will cause C1 to charge to -0.7 volts, until Q2 turns on. Once that happens, the charge on C2 would cause the base of Q1 to go negative, turning it off. When that happens, current flowing through LED1  will start flowing through C1 and the base of Q2, turning it on even harder. Once Q2 has turned on, it will keep Q1 off until C2 charges to -0.7 volts.

Note that while the circuit would have a stable state with both transistors on and both capacitors reverse-biased by 0.7 volts, in practice the winky-blink circuit always starts oscillating rather than entering such a state.


We will now start with our process. First download your software HERE for Design Spark or HERE for EAGLE CAD, I use Design Spark most of the time.


STEP1: Layout

,,,hFirst we’re going to place all of the components in the correct place.


It can be a bit difficult to find the components, but design spark has a great function under view -> Model Source Bar where you could either look under categories or enter a RS Components stock ,number just select your country and search your components you need, enter the stock number and click use component the software will tell you in which library it save the component and you can go fetch it from there. Marked in red are the two ways to find the components you need.



STEP2: Connecting

Next we will connect the components together as shown in the image above, note that instead of a battery I have have added a two pole header, when we have the final product we will have two holes where you can solder in the battery leads or you can put headers in those same holes.


STEP3.1: Converting

From here you have a few options. First option is to simply click on translate to PCB.


and follow the easy steps. Your PCB will look something like this


This does not always come out like expected, in which case we will see how to fix this in Step 3.2

STEP3.2: Converting

If your results was not what you expected in Step 3.1, click on Tools -> Unroute Nets -> All Nets.


You will see that the tracks has disappeared and now there are thin yellow lines. These yellow lines are to show you how the components were connected.

If you chose not to follow the previous option you will have to insert the components manually again. If you did follow the previous option you now only move the components how you feel fit.

This is what mine looks like yours can be different.


STEP4: Wiring Compnents

For option 1 go to Tools -> Auto Route Nets -> All Nets


and follow the instructions.

For option 2 you have to add the track in manually as in the schematic.

Your end result may look different than mine, but in the end, we achieve the same product.


Note: Using option two may result in errors making the PCB useless. Yes option one may have error as well but only if your schematic was wrong. Some of these errors may prove to be fatal.

I hope this blog post enspires you to try your PC board design!

Control an Arduino via the HM-10 BLE module, from a mobile app on your smartphone

Control an Arduino via the HM-10 BLE module, from a mobile app on your smartphone

We found this incredible tutorial on how to use the HM-10 BLE module by Hammad Tariq

connections_hn10_arduinoIn this tutorial, you will learn about controlling a LED using HM-10 BLE module, Arduino and Evothings Studio.

Last Summer, I wrote a tutorial about controlling the lights of your home using Arduino and HC-05 bluetooth module. While, HC-05, HC-06 and HC-09 are still famous and available everywhere, they are essentially based on Bluetooth 2.0 technology. On the other hand, many new smartphones support only BLE (Bluetooth Low Energy or Bluetooth 4.0) instead of Bluetooth 2.0 or Bluetooth 1.0. The iPhone is most prominent of those smartphones as it’s supporting BLE since iPhone 4S, which was released nearly 5 years ago!

As I sat down to explore what options we have for prototyping a BLE enabled IoT device, the HM-10 came up as a prominent module in this space as it’s inexpensive and available everywhere. The module is also based on already familiar TI’s CC2541 BLE SoC. The module also has a few clones; one is called BT-05, another is called AT09, yet another is known as the SPP-CA HC-05/HC-06 or BT06, yet some clones are based on ZS-040 breakout boards just like HC-05.

There is an excellent post by Martyn Currey if you want to identify the module you have or want to explore the differences between them. Essentially, if your module is based on CC2541, that is BLE and you should be able to use this tutorial with the exception of UUID of the module, that I will explain later in the tutorial. Also, HM-10 and all other clones use AT commands for configuration, you can read the datasheets for reference but this tutorial or mobile app does not need you to use any AT command.

In addition to the HM-10 and Arduino, I will be using Evothings Studio to develop our mobile app. Evothings Studio is ideal for developing IoT mobile apps as it’s easy to use, gets you started in minutes even if you have “some” knowledge of JavaScript and HTML. Also, it has useful pre-built libraries and plugins, such as, for this example, the Evothings Studio already has necessary libraries to work with BLE, all you need is to write down a few lines of code to connect and send commands to your BLE module.

Step1: What you will need.

1 x HM-10 or anyother similar module
1 x Arduino Uno
1 x LED
1 x 220 ohm resistor

Step 2: Connect the circuit
  1. Connect 3.3V of Arduino to the VCC of HM-10
  2. Connect GND of Arduino to the GND of HM-10
  3. Connect D8 of Arduino to RX of HM-10
  4. Connect D7 of Arduino to TX of HM-10
  5. Connect D2 of Arduino to the long leg of LED along with a 220 ohm resistor
  6. Connect the short leg of LED with the GND of Arduino


HM-10 and Arduino Wiring Diagram



Step 3: Upload the Arduino Sketch

Go to my Github repository and download/copy-paste the Arduino sketch to your Arduino IDE. Upload the sketch to your Arduino.

Step 4: Download the Evothings Studio

You can skip to next step if you already have Evothings Studio and are familiar with it’s working.

Follow these steps:

  1. Download and install Evothings Workbench on your computer. Generate an anonymous Cloud Key further down on the download page, paste it into the Workbench software.
  2. Download Evothings Viewer app from an appstore (iOS, Android)
  3. Open Evothings Workbench and click on “Get Key” button
  4. Open Evothings Viewer app, provide your connection key and tap the “connect” button
  5. Once the connection is successful, go to “Examples” tab and click the “Run” button for the “Hello World” example

You should see the “Hello World” app loaded into the Evothings Viewer; that is how the whole development suite works together, whatever changes you will make in your app code, the Evothings Workbench will reload it in the Evothings Viewer, allowing you to preview your changes in real time!

Step 5: Developing the Mobile App

On Evothings Workbench, click “Run” for “BLE Scan” example and note down the name of your BLE module.

Clone or download this Github repository on your computer. Open “hm10-arduino-ble” example, go to “app folder”, drag & drop the “index.html” to “My Apps” tab of Evothings Workbench.

Now open “index.html” in your favourite code editor, check “app.connect” function to confirm if your module has the same name as written in the code, else change it with your module’s name.

Now click the “Run” for your new project entry in “My Apps” tab, the app should load in Evothings Viewer, press the “Connect” button. Once connected, use the buttons to switch your LED On/Off.

Tip: If you experience any difficulty in connecting with your module, first identify which module do you have and then search for it’s UUID (universal unique identifier) online. Correct UUID should be given in the app.ledOn and app.ledOff functions of index.html.

Code Explanation

As explained earlier, the Evothings Studio comes bundled with all necessary libraries to connect and get you started with BLE. Our example is making use of arduinoble and easyble libraries which are located in app/libs/evothings directory. See this tutorial on more details about them. As, for now, we don’t need to go in detail of how these libraries are working, we can just focus on the code in the “index.html” file.

Following block of code is used to connect to the BLE module:

app.connect = function()
'BT05', // Name of the module.
app.device = device;
app.showMessage('Connected! Touch buttons to turn LED on/off.');
app.showMessage('Connect error: ' + errorCode + '.');

In this block of code, we are providing the name of the module to the library function of evothings.arduinoble.connect, upon success, we show a success message.

Similarly, analyze following block of code:

// Turn on LED.
app.ledOn = function()
app.device && app.device.writeDataArray(new Uint8Array([1]), '0000ffe1-0000-1000-8000-00805f9b34fb');
// Turn off LED.
app.ledOff = function()
app.device && app.device.writeDataArray(new Uint8Array([0]), '0000ffe1-0000-1000-8000-00805f9b34fb');

In this block of code, we are calling library function app.device.writeDataArray to write 0 and 1 to the BLE module along with the UUID of HM-10 module.

In the Arduino sketch, analyze the following block of code:

void loop() {
int c;
if (mySerial.available()) {
c =;
Serial.println("Got input:");
if (c != 0)
// Non-zero input means "turn on LED".
Serial.println("  on");
digitalWrite(LED_PIN, HIGH);
// Input value zero means "turn off LED".
Serial.println("  off");
digitalWrite(LED_PIN, LOW);

In this block of code, we are reading the software serial of Arduino. We simply switch the LED on if we receive anything other than 0 on the software serial, similarly, if it’s 0, we turn the LED off.

You can also check the serial monitor of Arduino IDE to see what you are receiving on Arduino’s software serial.

Getting Started with NodeMCU with ESP8266 part 2

Getting Started with NodeMCU with ESP8266 part 2

In this tutorial we will control electrical devices like fans, lights, etc., using esp8266 from a web browser.  The Arduino sketch below shows how you can add html code (web page code) to to the NodeMcu board so it will give you a web page when connecting to it. The web page the NodeMcu shows you will have buttons you can click on to control relays that in turn will control lights and so on.
What makes this cool is that you can connect to your NodeMcu from your wireless network from any device that got a web browser, including your phone.
Note: Make sure your browser enabled devices and the NodeMcu board is on the same wireless network. Depending on your networking knowledge you can take this a step further and configure your wireless router to do port forwarding and dynamic DNS to access your NodeMcu from anywhere on the Internet. Another good idea is to setup your router to always assign the same IP to your NodeMcu board in your router’s DHCP settings.
The components that you will need for completing this project are very simple, you need to have a NodeMcu module and a relay, make sure you buy a 5v relay, which are very easy to use with esp chips, it doesn’t require an external power supply.
We tested and sell this NodeMCU board.
You can also use this board with the easy and powerfull LAU scripting language, more info can be found on the LAU website.

For this example project I have used a 2 relay circuit, but the actual program is wrote to connect four relays.

You can watch the above video on how it works and how to connect your browser to the ip address returned from esp, all the details are included in this video.

Copy the below arduino code and paste into your Arduino IDE, then upload the program to your nodemcu or any other esp devices that you are using, make sure to choose the correct port and board. also don’t forget to change the SSID and password to your Wi-fi settings.
This program for the esp8266 also will return the status of the device , which will in turn notify you when its is connected to the specified network and it will also tell you what IP it received from the router.

#include <ESP8266WiFi.h>

const char* ssid = “Your Network Name”;
const char* password = “Your Password”;

; //
WiFiServer server(80);

void setup() {
pinMode(5, OUTPUT);
pinMode(4, OUTPUT);
pinMode(0, OUTPUT);
pinMode(13, OUTPUT);
digitalWrite(5, LOW);
digitalWrite(4, LOW);
digitalWrite(0, LOW);
digitalWrite(13, LOW);

// Connect to WiFi network
Serial.print(“Connecting to “);

WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED) {
Serial.println(“WiFi connected”);

// Start the server
Serial.println(“Server started”);

// Print the IP address
Serial.print(“Use this URL to connect: “);


void loop() {
// Check if a client has connected
WiFiClient client = server.available();
if (!client) {

// Wait until the client sends some data
Serial.println(“new client”);

// Read the first line of the request
String request = client.readStringUntil(‘\r’);

// Match the request

if (request.indexOf(“/light1on”) > 0) {
digitalWrite(5, HIGH);

if (request.indexOf(“/light1off”) >0) {
digitalWrite(5, LOW);


if (request.indexOf(“/light2on”) > 0) {
digitalWrite(4, HIGH);

if (request.indexOf(“/light2off”) >0) {
digitalWrite(4, LOW);

if (request.indexOf(“/light3on”) >0) {
digitalWrite(0, HIGH);

if (request.indexOf(“/light3off”) > 0) {
digitalWrite(0, LOW);

if (request.indexOf(“/light4on”) > 0) {
digitalWrite(13, HIGH);

if (request.indexOf(“/light4off”) > 0) {
digitalWrite(13, LOW);

// Set ledPin according to the request
//digitalWrite(ledPin, value);

// Return the response
client.println(“HTTP/1.1 200 OK”);
client.println(“Content-Type: text/html”);
client.println(“”); // do not forget this one
client.println(“<!DOCTYPE HTML>”);
client.println(“<meta name=’apple-mobile-web-app-capable’ content=’yes’ />”);
client.println(“<meta name=’apple-mobile-web-app-status-bar-style’ content=’black-translucent’ />”);
client.println(“<body bgcolor = \”#f7e6ec\”>”);
client.println(“<h4><center> Esp8266 Electrical Device Control </center></h4>”);
client.println(“Device 1”);
client.println(“<a href=\”/light1on\”\”><button>Turn On </button></a>”);
client.println(“<a href=\”/light1off\”\”><button>Turn Off </button></a><br />”);
client.println(“Device 2”);
client.println(“<a href=\”/light2on\”\”><button>Turn On </button></a>”);
client.println(“<a href=\”/light2off\”\”><button>Turn Off </button></a><br />”);
client.println(“Device 3”);
client.println(“<a href=\”/light3on\”\”><button>Turn On </button></a>”);
client.println(“<a href=\”/light3off\”\”><button>Turn Off </button></a><br />”);
client.println(“Device 4”);
client.println(“<a href=\”/light4on\”\”><button>Turn On </button></a>”);
client.println(“<a href=\”/light4off\”\”><button>Turn Off </button></a><br />”);
client.println(“<table border=\”5\”>”);
if (digitalRead(5))
client.print(“<td>Light 1 is ON</td>”);

client.print(“<td>Light 1 is OFF</td>”);


client.println(“<br />”);

if (digitalRead(4))
client.print(“<td>Light 2 is ON</td>”);


client.print(“<td>Light 2 is OFF</td>”);


if (digitalRead(0))

client.print(“<td>Light 3 is ON</td>”);



client.print(“<td>Light 3 is OFF</td>”);
if (digitalRead(13))
client.print(“<td>Light 4 is ON</td>”);

client.print(“<td>Light 4 is OFF</td>”);


Serial.println(“Client disonnected”);


Getting Started with NodeMCU with ESP8266 part 1

Getting Started with NodeMCU with ESP8266 part 1

The first thing you need to know is that the ESP8266 WiFi chip is much more than just a WiFi chip. It also includes it’s own microprocessor, 16 input/output pins, 64 KiB of instruction RAM and 96 KiB of data RAM.

The ESP8266 chip can me run as a serial device from an Arduino but it can also be used as a stand alone device!

You can use this chip on a breakout board with a couple of components to create a stand alone Internet Of Things device. This is much more cost effective than an Arduino with a WiFi shield.

Thanks to the guys who ported the Esp8266 into Arduino IDE and helping all the Arduino users to easily program the ESP8266.

Most of this NobeMCU part 1 post discusses how to install the Esp8266 support for the Arduino and then a short script on how to blink an LED (the hello world in the electronics).

Firstly open the Arduino IDE and then go to the file menu and click on the preference sub menu in the Arduino IDE

Copy the below link into the Additional boards Manager URLs

Click OK to continue.

After completing the above steps , go to Tools -> board, and then select Boards Manager

Search for ESP8266 in the search bar and install “ESP8266 by ESP8266 Community”.

Once all the above are completed we are ready to program our esp8266 with Arduino IDE.

For this example I have used NodeMCU esp8266, if you are using any other vendor wifi chips or generic wifi module please check with the esp8266 Pin mapping which is very essential to make things works.

The reason why I used D7 pin for this example is , I uploaded the basic blink program that comes with the examples program in the arduino IDE which is connected with 13 pin of arduino. The 13th pin is mapped into D7 pin of NodeMCU.

Go to the tools menu and then the board sub menu and select the type of esp8266 you are using and select the correct COM port to run the program on your esp8266 device. For the Node MCU, select NodeMCU 1.0 (ESP-12E Module)


void setup() {
// initialize digital pin 13 as an output.
pinMode(13, OUTPUT);

// the loop function runs over and over again forever
void loop() {
digitalWrite(13, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(13, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second

Part 2 of this block post can be found here.

Arduino online training

Arduino online training

Arduino online training

What is better than an Arduino training kit? …..

Online Training To Go With It, of cause.

We WANT you to become the next extraordinary electronics maker and we want that journey to be fast and fun.

No more having to search around for hours to try and find answers on your questions. And even more importantly – you have full access to the trainers to get you unstuck when running into problems.


Direct access to the trainers to keep you moving along smoothly

Training material

Step by step PDF’s, videos, datasheets and resources all in one place.


More than 150 quiz questions. Test your understanding and learn those things you missed


Forums are used to view questions and answers from fellow students and to ask your own.

18 Projects to build!

Building and experimenting with what you learn is crucial and it is also the fun part of your training. Each topic covered is accompanied with practical projects to make sure you can not just study but DO!

Its simple, start from the top and work your way trough each of the 21 topics. Each topic consist of training materials, component datasheets, quizzes and a link to the forum section.

No guessing or searching for hours to find information, everything you need regarding a topic is available in the topic.


Our forums will be one of the most important resources for you. Here you will find questions and answers from other students and that is a learning experience in its own.

You can also post your own questions and unlike other forums you might have seen we will answer questions in detail. Each forum section is covering a specific training topic so that you can focus specifically on the topic.


Quizzes might not sound like a training resource but it is an important one.

It does not only test your understanding and help you find information you might have missed but also gives you a great idea of what information is most important to know.

It makes you think more and view things from different “angles”. It also get you to re-study your training material so you go a second time over it.

It also help you to practice for the final exam if you are interested in a Bot Shop Maker Certificate.


Internet of things: Arduino + Blynk

Internet of things: Arduino + Blynk

Recently there is quite a swing with the term Internet of things. Wouldn’t it be nice if you can control your appliances with your smartphone.
Lets get started.

Step 1: Video

Step 2: Parts List

The part list for this project is super simple.

All you need is a Arduino, a LED, a computer with internet access and the Blynk app(running on either Android or iOS), and like most sketches the Blynk Library.

Step 3: Connections and Test

1.Connect one end of the usb to your arduino and the other to the computer having internet access.

2.Insert the led to Digital pin 13 as shown.(The shorter one is the cathode and goes to ground)

3.Install the Blynk app from google play store or app store.

4.Download the Blynk library from the link given.

5.Extract the zip file into Arduino’s library folder.

6.Now open the Arduino software,go to examples—>Blynk—->Boards_USB_serial—>Arduino_USB_serial

7.Enter the Authentication token from your email and then hit upload.

8.Go back to the Blynk library folder and under script open the windows batch file

9.Enter the COM port your Arduino is connected to.
Note:Make sure you do not close the command window.

*Now you are ready to blynk*

Step 4: Success!!!

Introducing the XLR8 FPGA-based Arduino Uno Clone

Introducing the XLR8 FPGA-based Arduino Uno Clone


that has the same footprint as an Arduino Uno,
but that runs like an Arduino Uno on steroids

Regular Arduino Uno

By default, the XLR8 behaves just like an Arduino, right down to its timing and 16 MHz clock. However, the XLR8’s clock frequency can be changed, and various functions — like the PWMs — can be implemented using XBs (“acceleration blocks”) inside the FPGA.

For example, the Arduino Uno doesn’t have a floating-point unit, which means it has to clunk along implementing floating-point operations using lots and lots of simple instructions. In turn, this means it executes floating-point operations verrryyy sslllooowwwlllyyy. By comparison, the XLR8 has dedicated floating-point hardware programmed directly into the FPGA’s fabric. Check out this video comparing an Arduino Uno and an XLR8 using floating-point math to generate Mandelbrot fractal images.

Using a Washer To Steady Joints While Soldering

Using a Washer To Steady Joints While Soldering

If you have “helping hands,” clamping wire leads against a washer, as shown, stabilizes the whole setup dramatically by connecting the two arms with a rigid member, so you can bear down a bit more with the iron without pushing things out of alignment. But the hole in the middle of the washer still allows all-round access to the junction.

If you don’t have helping hands, you can just use a washer, as shown, with a pair of alligator clips (or even small binder clips) as a pretty effective improvised workholding jig for this kind of soldering.


Joining wires, The NASA way

Joining wires, The NASA way

Some commenters on my post about using a washer as a soldering aid noticed my sloppy splicing technique and were kind enough to educate me about the so-called “Western Union splice,” aka the “Lineman’s splice,” which is the preferred method for twisting solid-core wire leads together for inline electrical connections.

Developed during the heyday of the telegraph, the Lineman’s splice is designed for connections that will be under tension. It is commonly claimed that, properly made, a Lineman’s splice is stronger than the wires of which it is composed. In any case, it is a time-proven method, and, coolest of all, one of NASA’s Required Workmanship Standards. To wit, in a NASA-approved Lineman’s splice:

  1. The conductors shall be pre-tinned.
  2. There shall be at least 3 turns around each conductor and the wraps shall be tight with no gaps between adjacent turns.
  3. The wraps shall not overlap and the ends of the wrap shall be trimmed flush prior to soldering to prevent protruding ends.
  4. Conductors shall not overlap the insulation of the other wire.

Though the Lineman’s splice was originally used without solder, today soldering is common. And NASA insists on it:

  1. Solder shall wet all elements of the connection.
  2. The solder shall fillet between connection elements over the complete periphery
    of the connection.

This material comes from page 84 of NASA-STD 8739.4 (PDF), which is a great reference if you’re interested in best practices for interconnecting cables and wires.