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Have an awesome project in mind using some LEDs. In that project I will be using some LED Fading Effect and few LED Chaser Circuits. But before jumping onto that, I thought I should create a short tutorial and show you guys how to fade a LED with or without an Arduino automatically or manually using a potentiometer. Video: https://youtu.be/IIUsdICycOw Sponsors This video is sponsored by PCBWay. PCBway: only $5 for 10 pcbs from https://www.pcbway.com/?from=CZcouple PCBWay specialize in manufacturing of very high quality, low-volume, colored PCBs at a very budgetary price. In addition to the standard PCBs, you can also order Advanced PCBs, Aluminum PCBs, FPC/Rigid-flex PCBs. They also provide PCB assembly and other related service which can meet your needs to the greatest extent. The ordering process from PCBWay is very easy. Once I had my design ready, I just had to upload the gerber file to the PCBWay's website and select the type, color and any other customization that I want and then just send it for fabrication. For my project, I choose the black color. PCBWay ships from china to most of the countries of the world within 3 to 7 business days. Talking about the quality, its absolutely mind-blowing. Without Arduino Lets first create the fader circuit without an Arduino. The base of this circuit is an operational amplifier IC named LM358. In this circuit, initially, the LED slowly glows with increasing brightness & after reaching its maximum brightness, the LED slowly dims its brightness and the process continues. Automatic Fading Components Required For the Non-Arduino bit we need: 1 x LM358 IC 1 x BC547 Transistor 1 x 0.47µF Capacitor 2 x 4.7KΩ Resistors 1 x 22KΩ Resistor 1 x 10KΩ Resistor 1 x 4.7MΩ Resistor 1 x 220Ω Resistor 1 x LED and a 9V Battery How This Circuit Works To get the fading effect we need to generate a series of triangular waves. Because of the triangular waves, the LED starts glowing slowly and then slowly dims off and the cycle continues. This setup is done using the LM358 IC. LM358 is a dual operational amplifier (Op-Amp) IC, integrated with two op-amps powered by a common power supply. Pins 1, 2, and 3 are one op-amp channel, and pins 5, 6, and 7 are the 2nd op-amp channel. As the capacitor charges and discharges the state of the PIN 3 switches from high to low and based on that the PIN 2 of the op-amp obtains the desire output. If you want to know more about this IC, please check out my "Tutorial No 21 : DIY - IR Module" : https://youtu.be/_M8FQIPi1qk. So, basically the op-amp here is used for voltage level detection. In this circuit, we are applying a voltage on positive pin (PIN-3) and the voltage to be detected is applied at negative pin (PIN-2). The transistor acts as a signal amplifier. You will need this if you are attaching a cluster of LEDs however for just 1 LED you can simply remove it. The Board So, this is how my board looks like in 2D and 3D. There are 15 breakout-boards in this 100cm x 100cm assembly. Component Assembly Now, lets solder all the components to the board. Lets first solder all the resistances to the board. Then lets solder the transistor followed by the capacitor to the board. After that lets solder the LED and the female pin header. To conclude the setup, lets solder the IC base and then install the IC into it. Demo So, this is how it looks like. Good thing about LEDs is that they can be easily controlled as compared to the traditional light bulbs. Which means you can easily change their intensity based on your need. Just by making a slight modification to this circuit you can change the brightness of a LED Lamp when someone walks in or out of a room. Manual Fading Using PWM Now, if you want to get the same dimming effect but want to manually control the intensity, you will have to find a way to modulate the pulse sent to the LED or group of LEDs using a potentiometer. I am going to do this by generating PWM Signals. What is PWM? Pulse Width Modulation, or PWM, is a technique for getting analog results with digital means. PWM value varies from 0 to 255. The bigger the value of PWM, the brighter the LED is and vice versa. - If PWM = 0, it is same as GND, so the LED will be OFF - If PWM = 255, it is same as VCC, so the LED will be fully ON To get varying analog values, you change, or modulate, that pulse-width. If you repeat this on-off pattern fast enough with an LED, the result is as if the signal is a steady voltage between 0 and 5v controlling the brightness of the LED. In this setup, we are going to use the 555 Timer IC in Astable mode (A free-running multivibrator that has NO stable states but switches continuously between two states this action produces a train of square wave pulses at a fixed known frequency) to generate the PWM Signals. 555 Timer IC will vary the voltage delivered to the LEDs to achieve the Dimming effect of the LED. Components Required For this setup we need: 1 x 555 Timer IC 1 x LED 1 x 220Ω Resistor 2 x 1N4007 Diodes 1 x 50KΩ Potentiometer 1 x 10nF Capacitor 1 x 100nF Capacitor and a 5V Battery How This Circuit Works Based on the charging and discharging timings of the Capacitor, a PWM Signal is generated at PIN 3 (OUT PIN) of the 555 Timer IC. The output is then sent to the LED to produce the dimming effect. Demo So, this is how it looks like. By rotating the knob of the 10K Pot we can adjust the brightness of the connected LED. With Arduino Now, lets repeat these setups using an Arduino. The beauty of Arduino is that it has 6 digital pins that can be used as PWM outputs (3, 5, 6, 9, 10, and 11). PWM signals are sent using the analogWrite() function by passing a value between 0 - 255. - analogWrite(255) requests a 100% duty cycle (always on), - and analogWrite(127) is a 50% duty cycle (on half the time), and so on. Components Required For this setup we need: Arduino UNO/Nano whatever is handy 1 x Breadboard 1 x LED 1 x 220Ω Resistor 1 x 10KΩ Potentiometer Automatic Fading Connect the positive leg of your LED to the digital output PIN9 of your Arduino through a 220Ω resistor. Connect the negative leg directly to the GND. That it, that's how simple it is. The Code After declaring PIN 9 as LedPin, and setting up the pinMode in the setup() section, we are going to loop through and dim the LED in the loop section. By gradually increasing the PWM value from 0 to 255, and then back to 0 we can get the fading effect. In this sketch, the PWM value is set using a variable called 'brightness'. Each time in the loop, it increases by the value of the variable 'fadeAmount'. If brightness is at either extreme of its value (either 0 or 255), then 'fadeAmount' is changed to its negative. So, if the fadeAmount is 5, then it is set to -5 and if it is -5, then it is set to 5. The next time through the loop, this change causes brightness to change its direction. A delay is added to control the speed of the fading effect. Demo So, this is how it looks like. Manual Fading Connect the positive leg of your LED to the digital output PIN6 of your Arduino through a 220Ω resistor. Connect the negative leg directly to the GND. Connect the left (or right) pin of the 50KΩ PoT to VCC and then connect the right (or left) pin of the PoT to the GND. Now, connect the 'data' pin of your potentiometer to the Analog PIN 'A0' of the Arduino. In this circuit, the potentiometer is working as a voltage divider. One of the outer pins is connected to the GND, the other to Vcc and the middle pin is the voltage output. The wiper position in this setup determines the output voltage. Now, lets have a look at the code. The Code Based on my setup, I set the LedPin as 6 and Potentiometer pin Pot as A0. Another variable 'Knob' is used to read and store the value of the potentiometer. pinMode of the LedPin is set to OUTPUT and we don't need to do anything for the PoT as its default value is already set as input. In the 'loop()' section I am first reading the value of the PoT using the 'analogRead()' function and then mapping its value between 1 to 255. A potentiometer intakes a value between 1 and 1024, but in our setup it has to be between 1 to 255. The 'map()' function divides the value read from the potentiometer into equal intervals of 1/255, which is then sent to the LED using the 'analogWrite()' function. Demo So, this is how it looks like. Thanks Thanks again for checking my post. I hope it helps you. If you want to support me subscribe to my YouTube Channel: https://www.youtube.com/user/tarantula3 Full Blog Post: https://diy-projects4u.blogspot.com/2021/02/led-fader-with-or-without-arduino.html Video: https://youtu.be/IIUsdICycOw Gerber File: 1. Gerber : https://drive.google.com/file/d/1w1hHZBFsXQR74ZTn04097awaAUqMndJi/view?usp=sharing The Code: 1. Automatic Fading : https://drive.google.com/file/d/1hab3sISIlurrPQBat80OLb90RXqQKzLZ/view?usp=sharing 2. Manual Fading Using PoT : https://drive.google.com/file/d/1TzXdVO5lVjPNaw_NPSUexIye3WZGJ6cj/view?usp=sharing Sketches: https://drive.google.com/file/d/1_WtmESof7kSyuJ_cmkkFZ8E8mdQXl3Z9/view?usp=sharing BTC: 1M1PdxVxSTPLoMK91XnvEPksVuAa4J4dDp LTC: MQFkVkWimYngMwp5SMuSbMP4ADStjysstm DOGE: DDe7Fws24zf7acZevoT8uERnmisiHwR5st ETH: 0x939aa4e13ecb4b46663c8017986abc0d204cde60 BAT: 0x939aa4e13ecb4b46663c8017986abc0d204cde60 LBC: bZ8ANEJFsd2MNFfpoxBhtFNPboh7PmD7M2 Thanks, ca again in my next tutorial.

A Chaser Circuit consists of a clocked IC or other electronic unit like an Arduino that drives an array of LEDs in such a way that individual LEDs (or small groups of LEDs) turn on and off in a predetermined and repeating sequence, thus producing a visually attractive display in which one or more ripples of light seem to repeatedly run through a chain or around a ring of LEDs. In this tutorial I am going to create 3 chaser circuits using Arduino and IC4017 decade counter. https://youtu.be/F6V1AjESWbU Sponsors This video is sponsored by PCBWay. PCBway: only $5 for 10 pcbs from https://www.pcbway.com/ PCBWay specialize in manufacturing of very high quality, low-volume, colored PCBs at a very budgetary price. In addition to the standard PCBs, you can also order Advanced PCBs, Aluminum PCBs, FPC/Rigid-flex PCBs. They also provide PCB assembly and other related service which can meet your needs to the greatest extent. The ordering process from PCBWay is very easy. Once I had my design ready, I just had to upload the gerber file to the PCBWay's website and select the type, color and any other customization that I want and then just send it for fabrication. For my project, I choose the black color. PCBWay ships from china to most of the countries of the world within 3 to 7 business days. Talking about the quality, its absolutely mind-blowing. Using IC555 and IC4017 Lets first create the chaser circuit using the IC4017 decade counter and IC555 timer IC. Components Required For the Non-Arduino bit we need: 2 x 4017 Decade Counter IC 1 x 555 Timer IC 1 x 10 K Potentiometer 1 x 1 Kilo Ohm Resistor 1 x 100 Ohm Resistor 1 x 100 MFD Capacitor 20 x Zener Diodes and 10 x Red LEDs Circuit Diagram 1. Forward Chaser The circuit is very simple. The 555 Timer IC operates as a clock oscillator or clock generator. The output on PIN-3 goes high causing a shift. The signal from the 555 IC clocks the 4017 decade counter. Output of 555 timer IC on PIN-3 is given as an input to 4017 IC through PIN-14. Whenever a pulse is received at the input of IC 4017, the counter increments the count and activates the corresponding output PIN. This IC can count upto 10, so we have attached 10 LEDs to the circuit. By increasing or decreasing the value of resistance of the 10K pot we can adjust the speed of the chaser circuit. Since only one LED will be turned on at a given time, I have attached just one 220ohm current limiting resistor to the cluster of LEDs. Demo: So this is how it looks like. 2. Forward Reverse Chaser using 2 x IC4017 Now, to give the forward and reverse effect we are attaching another 4017 IC to this circuit. If lets say the 1st IC connects from 1 to 10 (left to right) then the second one should connect from 10 to 1 (right to left). However, now we cannot connect the counter ICs directly to the LEDs as we did before. We have to use Diodes to stop the reverse flow of current to the 2nd IC. We have also lowered the value of the current limiting resistor to 100ohms as at a given time 2 LEDs will be on, one running from left and one from the right hand side. Demo: Now lets do a quick test. By lowering the speed I can get the desired forward and reverse effect. By removing one of the 4017 ICs we can get the effect that I demonstrated in the previous example. 3. Forward Reverse Chaser using 1 x IC4017 To get a forward reverse effect using one 4017 IC we need to connect 8 diodes to the circuit. The 1st and the 6th LED will be directly connected to the IC4017. The LEDs at the far end will get signals from only one pin however the one in the middle will receive signals from 2 x pins and hence we need diodes to stop the reverse flow of the current. Demo: So this is how it looks like. Using Arduino Now, I am going to repeat the same setup using an Arduino. Components Required For the Arduino bit we need: 1 x Arduino Uno/Nano (whatever is handy) 1 x 220 Ohm Resistor 10 x Red LEDs Few Connecting Cables The beauty of using an Arduino is that the setup remains the same for all the previously shown circuits, the only thing that changes is the code. So, I am going to use this simple setup for the rest of the tutorial. Circuit Diagram 1. Forward Chaser Code: The code for the forward chaser is very simple. Start by defining the constants and the global variables that will be used throughout the code. Then in the setup section define the pin modes. Now, in the loop section we are going to start by turning off all the LEDs followed by turning one LED on at a time. A counter is used to tell the loop which LED to turn on in the next cycle. Once the value of the counter reaches 10 (the maximum number of LEDs) the counter resets to 1 and the 1st LED lights up and the cycle continues. Demo: So this is how it looks like. 2. Forward Reverse Chaser Code: The code is same as the previous setup. The only thing that changes is the function that deals with the LEDs. In this setup we cycle through LED 1 to LED 10 and then reverse from LED 9 to LED 1. The counter resets when the max count is reached. Demo: So this is how it looks like. 3. Left-Right Chaser Code: The setup is exactly the same as the previous two setups. This function is the one which turns on the LEDs at the two far ends and then the one before that and likewise until they cross each other. The counter is reset when the max count is reached. Demo: So this is how it looks like. PCF8574 8-bit GPIO Port Extender Using a PCF8574 8-bit GPIO Port Extender we can add even more LEDs to this setup. PCF8574 becomes a life saver when you run out of pins on your Arduino. This "GPIO (General Purpose Input Output) pin extender" provides an additional 8 pins (P0 ~ P7) which can be used to 'output a signal' or 'read a signal as an input'. These modules run on the I2C bus, and if daisy-chained you can connect upto 8 of these devices in a project. Each device will give us an additional 8-bits of GPIO enabling 64 GPIOs in total. To know more about this IC please check out my tutorial number 10 : "PCF8574 GPIO Extender - With Arduino and NodeMCU". Thanks Full Blog Post: https://diy-projects4u.blogspot.com/2021/01/led-chaser-circuits-using-ic4017-and.html Video: https://youtu.be/F6V1AjESWbU Gerber File: 1. https://drive.google.com/file/d/108EUNylmearJgU_4qSlxNr9GAPGrLGRh/view?usp=sharing Code: 1. Forward: https://drive.google.com/file/d/1bw1la5oRMWZRXsfYJ41qNbCoEkJsZHBM/view?usp=sharing 2. Forward Reverse: https://drive.google.com/file/d/1Oag8kxbvfxZg7StFrYzWwtcqQx6okwzd/view?usp=sharing 3. Left Right: https://drive.google.com/file/d/17ZEsKU3OFrcjaJpvyUJMQbHQ-lznbp0H/view?usp=sharing Sketch: 1. With Arduino: https://drive.google.com/file/d/1YHWvpkDbGbGVHwX65HwvwS3_JyFwZdK9/view?usp=sharing 2. Without Arduino: https://drive.google.com/file/d/1LdxcS1BXf3GtQTRhWCoCZKm6ppRwsc5k/view?usp=sharing BTC: 1M1PdxVxSTPLoMK91XnvEPksVuAa4J4dDp DOGE: DDe7Fws24zf7acZevoT8uERnmisiHwR5st LTC: LedWPdTaUzr5iaJx8garkcykSs1DZU1FAx ETH: 0xB62a901Ee6cE24f3153CA6ae565C2A6533066faA BAT: 0xB62a901Ee6cE24f3153CA6ae565C2A6533066faA BCH: 14xJhpswSAQi375S39yDFsrBFtDoiLVX1J

With a BLE5.0 & Dual-band WiFi microcontroller, you will never have to worry about re-compiling the code just to change the WiFi ssid and password. Ameba RTL8722 is a BLE5.0 and dual-band WiFi (2.4G & 5G) Iinternet-of-Things (IoT) developing platform that suit the need for many IoT application scenarios. Taking advantge of its BLE + WiFi combination, we can easily change Ameba's WiFi setting and save us great deal of time. Take a look at the short video below to learn more https://youtu.be/TA4A-VXbImo

Most of time when we use WiFi, we only use our WiFi device as a "station"(STA) that mainly receive information sent from "access point" (AP). Ameba Microcontroller from Realtek can not only connect to WiFI as a station, but also broadcast its own signal and become an AP, here is how, In AP mode, Ameba can accept at most 3 station connections, and can be set to open mode or security mode (WPA2). Preparation Ameba x 1 Example In this example, we turn on the AP mode of Ameba and connect station to Ameba. Open the WiFi AP example, "File" -> "Examples" -> "AmebaWiFi" -> "WiFiAPMode" In the snippet highlighted in yellow, fill in your SSID, PASSWORD and CHANNEL. The snippet highlighted in pink is the API we used to turn on the AP mode in security mode. If you want to turn on the AP mode in open mode, please modify the code to status = WiFi.apbegin(ssid, channel); Then upload the sample code and press reset, and you can see related information shown in serial monitor. In the figure below, we show the messages shown in serial monitor when two stations connect to Ameba AP in open mode: In the figure below, we show the messages shown in serial monitor when a station connects to Ameba AP in security mode:

Many interesting projects are coded on Arduino IDE thus making it very easy to get a head start with project. Just like Realtek Ameba RTL8722, there are many interesting project worth trying out, like BLE, MQTT with TLS etc. However, once the project grows in length and complexity, it becomes super inconvenient with the lack of code completion, hinting and jumping to definition features that are commonly available on most popular code editors. However, there is actually a way to have all those features with only 3 steps, here is how, (Note: there are probably other ways of achieving the same goal, so share your method if you know a better way;) 1. Go to “preference” under Arduino IDE and select “use external editor” With this option selected, you will see the arduino editor grey out and become unable to edit code anymore, don’t worry, this is ok. 2. Download and open any of your favourite editor which has all these “smart features” In this case, Visual Studio Code is used for demonstration. 3. Create a folder to store all your sketches and add Ameba RTL8722 ‘s arduino library to the workspace (this 3.0.4 is the ameba library folder and it is usually located in you C drive under “C:\Users\YOURUSERNAME\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD”) And also don’t forget to add your own sketch folder to the workspace (here my sketch folder is named “arduino_sketch” as seen above). With these steps done, it will only takes a couple of seconds before the editor parse each and every files in the folders added and link all symbols together. Now you will be able to code in your favourite editor and also to have these convenient features, # Code Completion # Code Hinting # Jump to definition Every time you save the sketch you just modified, just click anywhere of the grey area on the arduino editor and it will be automatically updated with your latest modifications, so you will still be able to one-click compile/download your code using the “Verify” or “Upload” button. Hope you find it useful and share with me how you like to code for Arduino project 🙂

We have shared several posts before about how to build a remote control car and how to implement live video streaming using an Arduino sized microcontroller Ameba RTL8195 from Realtek, this time we will try to put all these together and create a fun project -- a DIY RC surveillance patrol car. here is how it is done, Preparation Ameba x 1 L298N H-Bridge x 1 4-wheel motorcar or 2-wheel motorcar+Universal wheel x 1 Android Phone x 1 Logitech C170 web cam x 1 Mirco USB OTG adapter x 1 18650 Li-ion battery >= 2 18650 batter holder x 1 Example Power source In previous examples, we use portable power bank as power source and use Ameba to supply power for L298N Bridge and the motor. However, in this example we connect a webcam additionally. To provide sufficient power, we use two 18650 batteries as power source. A typical 18650 battery is 3.7V. For safety concern, please keep the battery in cool temperature, and use stable voltage to charge the battery. We connect the two batteries in series to provide 7.4V voltage. L298N Bridge accepts 7V to 12V power. We connect the batteries to L298N. There is a 5V power output on L298N, we can use it as the power supply for other components. Wiring The detailed wiring diagram: Download AmebaMotors library and run the example Please download AmebaMotors library version 1.0.3: https://github.com/ambiot/amb1_arduino/raw/master/Arduino_libraries/AmebaMotors-1.0.3.zip And install the library to Ameba: https://www.arduino.cc/en/Guide/Libraries#toc4 Note that if you have installed AmebaMotors v1.0.1, please remove it before installing v1.0.3. Find the location of the library in "File" -> "Preferences", the "Sketchbook location" is where Arduino IDE stores sketches and libraries. For example, in the figure below, the Sketchbook location is "D:\workspace\arduino", then the AmebaMotors library is located in "D:\workspace\arduino\libraries\AmebaMotors". Please remove old version first, then install version 1.0.3. Open the example in "File" -> "Examples" -> "AmebaMotors" -> "car2wd_mobile_plus_uvc", then follow the steps： 1. Upload: Upload the sample code to Ameba 2. Wiring: Connect the components as the wiring diagram in previous section. 3. Download App: you can download and install it directly here: Car Remote 2.0 4. Connect android phone to Ameba: Go to "Settings" -> "Wi-Fi", find the SSID "mycar", enter password "12345678" and confirm that the android phone is connected to "mycar". Below is the demo video of this example: Code Reference Details of controlling the motorcar: AmebaMotors – Use Mobile Phone To Control Motorcar Remotely Details of controlling UVC: UVC - Video Streaming

Realtek's ameba dev. board is capable of USB OTG and SDIO thus making it possible to take photo with a UVC camera and store it in a SD card via SDIO. Here, combining these 2 function, one can easily create a Time Lapse Photography with merely an arduino size MCU. Here is a tutorial about it, Preparation Ameba x 1 SD card or MicroSD card x 1 SD sniffer x 1 (optional) Logitech C170 web cam x 1 Micro USB OTG adapter x 1 Example In this example, we use UVC to take photos and save to SD card at regular time, which is similar to time lapse photography. Open the sample code in "File" -> "Examples" -> "AmebaSdFatFs" -> "time_lapse_photography" In the sample code, we start the UVC at first, then initialize SD FAT FS. In loop(), use UVC to capture photo every three seconds, and the captured photos are numbered in 0001.jpeg, 0002.jpeg, 0003.jpeg, ... There are some tools to turn these photos to a video. We use ffmpeg here: https://ffmpeg.org/ In Windows OS environment, type the command in the directory of all UVC photos: ffmpeg -framerate 30 -i %04d.jpeg -vf fps=30 -pix_fmt yuv420p output.mp4 The explanation of the arguments in the command: -framrate: By specifying this argument, you tell ffmpeg to use the time handled by framerate to be the timeline. Here we use 30, which means in 30 photos are displayed per second. -i: use this argument to specify input file name. We use "%04d.jpeg" to tell ffmpeg to read the files from 0000.jpeg, 0001.jpeg, 0002.jpeg, ... fps: the framerate of output video, we use 30 frames per second here. The last argument is the output file name. Demo video: Code reference The sample code is comprised of two parts: use UVC to capture photo, and write file to SD card. The UVC part please refer to previous "UVC – Use UVC To Send Image" example. And SD part please refer tp the "SDIO – Edit Files In SD Card" example

LoRa is a low-power wide-area network protocol developed by Semtech. It has a typical range of 10KM at low power consumption which is ideal in some IoT applicaitons. Using LoRa on Realtek's Ameba Dev. board is very easy, here is a tutorial about it, Materials Ameba x 1 Dragino LoRa Shield x 2 Example Dragino Lora Shield is a long range transceiver and based on Open source library. It allows the user to send data and reach extremely long ranges at low data-rates.It provides ultra-long range spread spectrum communication and high interference immunity whilst minimising current consumption. Due to different frequency regulations on each country, please notice the frquency LoRa Shield used when you purchase it. Download the LoRa Library: https://github.com/ambiot/amb1_arduino/raw/master/Arduino_libraries/AmebaLoRa.zip Refer to the documentation on Arduino website to install library and add the .zip file to Ameba： https://www.arduino.cc/en/Guide/Libraries#toc4 Dragino LoRa Shield SPI example wiring explanation: Dragino LoRa Shield can be embedded on Ameba board directly, but the Ameba CS pin is different to the standard SPI protocol. Therefore, Dragino LoRa Shield CS pin cannot connect to Ameba CS pin directly. Modify and pull the CS pin which is pin 10 toward inside and connect to pin 0 with dupont line on Dragino LoRa Shield. The example is shown below: Dragino LoRa Shield SPI Data is produced from ICSP SPI BUS, then connect to AMEBA SPI pin as follows: Below is the RTL8710 Wiring Diagram: Example Illustration This example uses send and receive code to do the functional verification for two Dragino LoRa Shield. One is for sender and another one is fr receiver. Open “File” -> “Examples” -> “AmebaLoRa” -> “LoRaSender” and LoRaReceiverCallback. Compile them separately and upload to Ameba, push the Reset button. Then you can see the results on the terminal:

Lack of security consideration is always debated in DIY projects, but now with Ameba Arduino-- an ARM Cortex M3 based WiFi microcontroller, you can add fingerprint sensor to your personal DIY project and boost its security. Here is a demo Preparation Ameba x 1 AS606 fingerprint identification module x 1 Example In this example, a fingerprint identification module is used to store fingerprints and identify them. This module uses SYNOCHIP AS606 chip, which can store up to 1000 sets of fingerprints. The libraries we need are: https://github.com/ambiot/amb1_arduino/raw/master/Arduino_libraries/AmebaFingerprint.zip For the way to install the library, please refer to the teaching article of the Arduino official website to add the zip file library to Ameba: https://www.arduino.cc/en/Guide/Libraries#toc4 This module uses UART to communicate with AMEBA. In addition to VCC (3.3V) and GND, and using UART TX and RX lines, we turn the module to the back. The RTL8195 example wiring is as follows: The RTL8710 example wiring is as follows: We open the example "File" -> "Examples" -> "AmebaFingerprint" -> "enroll", compile and upload to Ameba and press the Reset button. At this point, open the terminal and you should see the fingerprint identification module message: Then follow the message at the console prompt, we type a letter 'a’ on the keyboard. The console prints the "waiting for valid finger to enroll" message, and you can place your finger on the module window. If the module has correctly collected the fingerprint, then it will ask to remove the fingerprint and then place the same finger on the window. If the fingerprint is collected correctly, the console will mention printfs matched and store the fingerprint. Then you can try to collect more fingerprints from different fingers. Then we have to test whether the fingerprint identification module can successfully identify the fingerprint that has just been stored. We open the example "File" -> "Examples" -> "AmebaFingerprint" -> "fingerprint", compile and upload to Ameba and press Reset button, open the terminal at this time, you should see the message that can find the fingerprint identification module: And the prompt is waiting for the verification fingerprint, at this time, place the same finger just sampled in the fingerprint recognition window. The Console will display the message "Found ID #x with confidence of xx", which means the identification is successful.

Ameba RTL8195AM has onboard NFC tag and run on ARM Cortex-M3 core with WiFi, just nice to make use of all these 3 powerful tool to make an useful applicaiton. Many models of Android smart phone support NFC feature, and numerous of NFC applications are developed for inspection and modification of NFC Tag. In this example, we establish NFC connection between Ameba and a smartphone, and open a webpage on the smartphone via a NFC event. Preparation Ameba x 1 Smartphone with NFC feature x 1 Note: Make sure the onboard NFC antenna is safely connected to the module. Then open the example, "File" -> "Examples" -> "AmebaNFC" -> "UriWebPage" and upload, you will see this message when you tap your NFC-enabled phone on Ameba For more details, refer to the offical website at https://www.amebaiot.com/en/ameba-arduino-nfc-open-web/ Also feel free to join the Facebook group to discuss with other makers! https://www.facebook.com/groups/AmebaIoT

With COVID-19 still wreaking havoc globally, causing thousands of deaths, millions hospitalized, any useful medical device is on high demand, especially household medical device like IR non-contact thermometer. Handheld thermometer usually is on high price point and is hard to come by these days, but the components needed to make thermometer are not that expensive, that give us the perfect reason to DIY one during this lockdown period. This ThermoGun project use Ameba Dev. board RTL8710AF from Realtek, which connects to an OLED display to show temperature data obtained from the MLX90615 IR sensor. Pushing the push button not only perform data acquisition and visualization, but also publish the data via MQTT to all subscribers. Note: The MQTT service used in this project is a FREE MQTT broker hosted at cloud.amebaiot.com, which need to register at www.amebaiot.com . Details of registration is at the link below, https://www.amebaiot.com/en/cloud-getting-started/ For details of step-by-step guide and connections, please refer to Github page here, https://github.com/Realtek-AmebaApp/Ameba_Examples/tree/master/RTL8195AM/007_THERMOGUN Demo Video: https://youtu.be/Yl3arBRmyYI

Hello.Looking for information on the fastest arduino infrared temperature sensor.If there are sensors out there that can sense between 100 and 300 ms,sensors don't have to be arduino,but there must be ready made interface boards and compatible software.Any assistance will be greatly appreciated. Thank you Regards Arthur

Accessing internet service is an easy job for a smart device like an android phone, tablet or a PC, but not so easy on microcontrollers since it usually requires better connectivity and processing power. However, we may offload the heavy part of the job to IFTTT to help us accomplish a great variety of internet service with ease. This tutorial will show you how to make use of IFTTT to do just that. Introduction to IFTTT IFTTT, known as If This Then That, is a website and mobile app and free web-based service to create the applets, or the chains of simple conditional statements. The applet is triggered by changes that occur within other web services such as Gmail, Facebook, Telegram, Instagram, Pinterest etc. Preparation Ameba x 1 An account from https://ifttt.com/ , in order to access IFTTT service* For detailed step-by-step guide, you may refer to link below, https://www.amebaiot.com/en/ifttt-via-ameba/

Now that most people stay at home to avoid close contact with potential COVID-19 virus carrier, air quality becomes an important factor to people’s well-being, especially in tropical countries where using air-con is a must during the day, as prolonged use of air-con may do more bad than good to people’s respiration system thus weakening our immunity and make people more susceptible to virus infection. Here I am going to show you how to make a simple yet powerful air quality monitoring system using Realtek Ameba RTL8195AM development board and PM2.5 module, together with a TFT LCD display to create a colourful interface. Preparation § Ameba x 1 § ILI9341 TFT LCD with SPI interface x 1 § Plantower PMS3003 or PMS5003 x 1 Example This example extends previous PM2.5 example to show the PM2.5 concentration on the LCD. Wiring of QVGA TFT LCD: (Note: PMS3003/PMS5003 sensor requires 5V voltage) Open the example, "Files" -> "Examples" -> "AmebaSPI" -> "PM25_on_ILI9341_TFT_LCD" Compile and upload to Ameba, then press the reset button. Then you can see the concentration value of PM1.0, PM2.5 and PM10 on the LCD. Code Reference In this example, first rotate the screen by 90 degrees, and draw the static components such as the circles, the measuring scale and the title text. After the concentration value is detected, it is printed inside the circle. To know more about the details, click the link below, https://www.amebaiot.com/en/ameba-arduino-spi-lcd-pm2-5/

MQTT (Message Queuing Telemetry Transport) is a protocol proposed by IBM and Eurotech. IBM® Watson™ IoT Platform is, by the official definition, “A foundational cloud offering that can connect and control IoT sensors, appliances, homes, and industries. Built on IBM Cloud, Watson IoT Platform provides an extensive set of built-in and add-on tools. Use these tools to process IoT data with real-time and historical analytics, extract key performance indicators (KPIs) from your data, add “smarts” in the cloud for non-smart products, and securely connect your own apps and existing tools to the Watson IoT Platform infrastructure.” (IBM, 2020) This platform provides easy web interface to register, connect and visualize our IOT devices. For quick start and simple try-out, registration is not necessary, we may just run our program to get the device ID needed for this platform. Preparation § Ameba x 1 Example In this example, we will take a look at how to make use of IBM Watson IOT platform for out IOT project. Open the MQTT example “File” -> “Examples” -> “AmebaMQTTClient” -> “ibm_watson_iot_quickstart” Make sure the Wi-Fi information is properly filled in and we are ready to upload the code to ameba. Once uploading finished, open a serial monitor and we shall see information as follows, Important: Please take note of the string of characters on the first line of the picture above -- “clientId:quickstart:iotsample-ameba:ac35ee15608e” “ac35ee15608e” is the device ID as well as the MAC address of the ameba board used here which will NOT be the same for other cases, so make sure to copy down the device ID displayed on your serial monitor. Next, we click the IBM IOT platform link provided here and open our browser: https://quickstart.internetofthings.ibmcloud.com/#/ Paste the device ID we just copied into the box highlighted below, If the device ID keyed in is correct, some fake temperature data that our ameba published will be visualized like this, Done! Now you have FREE and working IOT cloud platform to help you visualize your IOT data in realtime~

This project is the second one in the new IOT project series on Ameba RTL8195AM Dev. Board. The focus of this project is to demonstrates how easy it is for Ameba Wi-Fi Dev. board to communicate with our smart phone via MQTT protocol. Phone to microcontroller communication used to be very difficult as they use totally different hardware interface and phone get its data mainly through the network. Now with a Wi-Fi enabled microcontroller like Ameba RTL8195AM, communication with our phone becomes a bliss. Of course, in this project, only a mini hand-crafted window is used for demonstration purpose but controlling a real window should not be a problem if you simply replace the servo motor with a bigger DC step motor and change the source code accordingly. With this smart curtain system, you may, 1. Remotely control your curtain to open or close instantaneously 2. Check your curtain status according to the MQTT message received 3. Link with the previous weather station project and automate your room from there Hardware List of hardware needed Ameba 1 RTL8195AM x1 Servo motor x1 Jumper wires x3 DIY materials x3 Hardware connection is shown below, for the window, you may use a Lego house as substitute or simply build one using plywood or hard form board, the exact structure can also be found in this folder. Software 1. Check and make sure you have installed the ameba 1 board to Arduino IDE via adding this link into “additional boards manager URLs” under “Preference”, and install it in “board manager” under “Tools”, https://github.com/ambiot/amb1_arduino/raw/master/Arduino_package/package_realtek.com_ameba1_index.json 2. Upload source code to your Ameba1 RTL8195 board using arduino IDE 3. Install a MQTT client App on your smart device (android/iOS) a) To use a MQTT service, you must first get a free MQTT server address b) Go to www.amebaiot.com and register for a user c) Then go to cloud service tab and register your device d) Once approved, the same username and password used for registration can be used to make use of the MQTT service for free 4. Connect to your MQTT server by keying in the correct server address, port number, username and password • For Host name: cloud.amebaiot.com • For Port number: 1883 • For username: same as your amebaiot.com username • For password: same as your amebaiot.com password 5. Key in the topics that you specified in the code, always remember to swap the publish topic and subscribe topic when you want to monitor your microcontroller’s published data.

Temperature and humidity are 2 of the most important factors affecting people’s comfort level in an enclosed space. The DHT humidity and temperature sensor can read the ambient temperature and humidity every 2-3 seconds, and then pass the data to Ameba who will forward them to the server using MQTT protocol. Whoever “subscribing” to the right topic gets the data almost instantaneously. Users can then adjust the aircon mode or temperature according to the readings received. An android phone was used as an MQTT client and the Ameba RTL8195 Dev. Board acted as another MQTT client communicating with the android phone. Both clients have to connect to the same MQTT server before proceeding to the next step. The DHT sensor updates its data every 10 seconds to stay as accurate as possible. Once sensor data is received, Ameba then “publishes” the data to the MQTT server where all clients “subscribing” to the right topic gets the data displayed on the console. GitHub page https://github.com/Realtek-AmebaApp/Ameba_Examples/tree/master/RTL8195AM/003_DHT_MQTT Official pages https://www.amebaiot.com.cn/en/ https://www.amebaiot.com/en/ Facebook pages https://www.facebook.com/groups/AmebaIoT/ https://www.facebook.com/groups/AmebaIoTWW/ BiliBili channel https://space.bilibili.com/45777743

This is a simple IoT project based on the “mqtt basic” example that comes with the Arduino package when you install the RTL8195 on Arduino IDE. In this project, simple passive components are used to aid in demonstrating the power of bidirectional communication of MQTT protocol which is widely used in modern IoT applications for its advantages in speedy response and lightweight. In the video, an android tablet was used as a MQTT client and our Ameba RTL8195. Board acted as another MQTT client communicating with the android tablet. Both client have to connect to the same MQTT server before proceeding to the next step, you may choose to set up own MQTT server or using an online free server. Please refer to the video link, GitHub source code, https://github.com/Realtek-AmebaApp/Ameba_Examples/tree/master/RTL8195AM/002_MQTT_BASIC Official pages https://www.amebaiot.com.cn/en/ https://www.amebaiot.com/en/

I have just started with the youtube channel, so I decided to make a Bluetooth controlled robotic car. As am an electronics engineer I have knowledge about electronics. but I don't know how to build a custom android application. so Before making the project I learn about MIT app inventor and try to make one app which was a great success it is quite easy to do. In this article, we will learn how to make a custom Android application and how to configure the Bluetooth module with Arduino. Hardware requirements: Arduino Uno Bluetooth HC-05 l298n motor Driver acrylic sheet wheels x2 geared dc motor x2 mini breadboard 4.7k, 2.2k resistor jumper wires 12v battery 9v battery switch Step 1: Building Chassis I used an acrylic sheet length of 18cm and width of 13cm. First, I positioned all parts that going to be mounted on the chassis. then I used a hot glue gun to stick the parts to acrylic you can use spacers or screws. after mounting all parts I stick the caster wheel at the bottom of the chassis. Step 2: Connection Make the connection according to the circuit diagram. we can use separate power for Arduino. Motor driver and 12v battery connected through the switch. As we can see in the circuit diagram there is 2.2k and 4.7 k resistor connected to the pins of the bluetooth module. the main reason for this is the HC-05 Bluetooth module uses a logic level of 3.3v. While transmitting data from HC-05 to Arduino there is no problem because Arduino is capable of receiving data from 3.3v logic, but while receiving any data from Arduino to HC-05 Arduino uses 5v logic which may damage our Bluetooth module, to convert 5v logic level to 3.3v we use a voltage divider method. Make sure that there is common ground between motor driver and Arduino otherwise motor not work. Step 3: Programming /* Author:DIYelex date: 3/8/2019 */ #include <SoftwareSerial.h> // TX RX software library for bluetooth SoftwareSerial mySerial(2, 3); // Connect the TXD pin of BT module to pin 2 of the Arduino and the RXD pin of BT module to pin 3 of Arduino. int Rightmotor1 = 4; //pin 1 of Rightmotor int Rightmotor2 = 5; //pin2 of Rightmotor int leftmotor1 = 6;//pin1 of leftmotor int leftmotor2 = 7;//pin2 of leftmotor int en1=9; //enable pin for Rightmotor int en2=10; // enable pin for leftmotor String readString; void setup() { pinMode(Rightmotor1,OUTPUT); // attach Right Motor 1st wire to pin 4 pinMode(Rightmotor2,OUTPUT); // attach Right Motor 1st wire to pin 5 pinMode(leftmotor1,OUTPUT);// attach Right Motor 1st wire to pin 6 pinMode(leftmotor2,OUTPUT);// attach Right Motor 1st wire to pin 7 pinMode(en1,OUTPUT); //attach motor drivers rightmotor enable pin to PWM pin 9 of arduino pinMode(en2,OUTPUT);//attach motor drivers leftmotor enable pin to PWM pin 10 of arduino Serial.begin(9600); //Setup usb serial connection to computer mySerial.begin(9600);//Setup Bluetooth serial connection to android } void loop() { while(mySerial.available()){ delay(50); char data = mySerial.read();//store the data come from bluetooth to char data readString+=data; } if(readString.length() > 0) { Serial.println(readString); ///Print the data to serial monitor which is given by bluetooth if(readString == "Forward"){ //if forward received do following digitalWrite(Rightmotor1, HIGH); ////////////FORWARD //////////////////////// digitalWrite(Rightmotor2, LOW); digitalWrite(leftmotor1, HIGH); digitalWrite(leftmotor2, LOW); analogWrite(en1,200);// for controlling speed of Rightmotor vary the value from 0 to 255 analogWrite(en2,200);// for controlling speed of leftmotor vary the value from 0 to 255 } if(readString == "Back"){ //if Back received do following digitalWrite(Rightmotor1, LOW); ////////////BACK///////////////////////////// digitalWrite(Rightmotor2, HIGH); digitalWrite(leftmotor1, LOW); digitalWrite(leftmotor2, HIGH); analogWrite(en1,200); analogWrite(en2,200); } if(readString == "Left"){ //if left received do following digitalWrite(Rightmotor1, HIGH);/////////////LEFT//////////////////////////// digitalWrite(Rightmotor2, LOW); digitalWrite(leftmotor1, LOW); digitalWrite(leftmotor2, HIGH); analogWrite(en1,80); analogWrite(en2,80); } if(readString == "Right"){ //if Right received do following digitalWrite(Rightmotor1, LOW);/////////////RIGHT//////////////////////// digitalWrite(Rightmotor2, HIGH); digitalWrite(leftmotor1, HIGH); digitalWrite(leftmotor2, LOW); analogWrite(en1,80); analogWrite(en2,80); } if(readString == "Stop"){ //if stop received do following digitalWrite(Rightmotor1, LOW); ///////////stop///////////////// digitalWrite(Rightmotor2, LOW); digitalWrite(leftmotor1, LOW); digitalWrite(leftmotor2, LOW); } readString = ""; } } Step 4: Android App Now we have to build Bluetooth applications that would be capable of controlling your robot car. If you wish to download my application you can download it from github: The Bluetooth car How I created this application was through App Inventor 2, The images above show both the "Designer" & "Block" view of my application so you can build and change thing up if you wish! Steps for configuring bluetooth First turn on the switch of robot car Go to setting Click on the Bluetooth TabTurn Bluetooth on Wait for your phone to find the HC-05 Bluetooth module Once it has been found click it and input the password by default it should be either "1234" or "0000" Now open the application Bluetooth car Application and click the " Bluetooth image" button You should see the HC-05 Module (If not re-try the steps above) click on the Module The Application will then return automatically to the main screen and you can see the green text "connected" At this point, the HC-05 Modules Red LED should now be constantly on instead of pulsing meaning a device is currently connected. Conclusion Thanks for Reading watch this project video on youtube https://youtu.be/iC7P9nyFu9I

AI Smart agriculture control Device Abstract: Agriculture is the broadest economic sector and plays an important role in the overall economic development of a nation. Technological advancements in the arena of agriculture will ascertain to increase the competence of certain farming activities. Smart Farming is a farming management concept using modern technology to increase the quantity and quality of agricultural products. Farmers in the 21st century have access to LoRa, soil scanning, data management, and Internet of Things technologies, web. Our device focuses on the measurement of physical parameters such as soil moisture content, nutrient content, automatic irrigation, pH of the soil and automatic sent notification phone application that plays a vital role in farming activities. Keyword: Agricultural innovation, IoT, LoRa, Power Management, ARM, Data Management Introduction: Smart farming based on IoT technologies will enable growers and farmers to reduce waste and enhance productivity ranging from the quantity of fertilizer utilized to the number of journeys the farm vehicles have made. In IoT-based smart farming, a system is built for monitoring the crop field with the help of sensors (light, humidity, temperature, soil moisture, etc.) and automating the irrigation system. The farmers can monitor the field conditions from anywhere using smart app. IoT-based smart farming device is highly efficient when compared with the conventional approach. The applications of IoT-based smart farming not only target conventional, large farming operations, but could also be new levers to uplift other growing or common trends in agricultural like organic farming, family farming (complex or small spaces, particular cattle and/or cultures, preservation of particular or high quality varieties etc.), and enhance highly transparent farming. Now, let’s discuss the major applications of IoT-based smart farming device that are revolutionizing agriculture. Hardware: Soil Sensor: The Soil Moisture Sensor uses capacitance to measure the water content of soil (by measuring the dielectric permittivity of the soil, which is a function of the water content). Simply insert this rugged sensor into the soil to be tested, and the volumetric water content of the soil is reported in percent. Temperature sensor (DHT 11): Measure the Temperature and humidity Photoresistor (LDR): Check day or night position LoRa ARM development board : This is a low power single board computer inbuild Wi-Fi, LoRa connectivity also has Digital and analog pins. Smart Agriculture Device Features: 1.This device no need external power (inbuild 5-volt Power bank & solar cell), 2. real-time Soil Moisture sensor measure the soil and sent data to the Server, 3.Temperature, photoresistor measure the weather condition. 4. Both way communication (device can send notification & received command from web or app) 5. Dual control (Device ca run manual mode and automatic mode). 6. Dual communication (LoRa and wi-fi mode) System Hardware Implementation: First configure the FreeRTOS on EFB-REV1 board after successful configure of operating system we need configure GPIO library(J-Tag) to access the its GPIO. Install 5-volt solar cell and power bank for powerup the device 24x7. Soil Sensor connected to analog pin of A0, DTH11 connected to A3, Photoresistor connected to A6. Analog sensors measure data and sent via wireless media. EFB_REV1 development come with LoRa, Wi-fi also Bluetooth, for our project we used Wi-Fi and LoRa. For Wi- fi communication need a wifi receiver module which receive and sent sensor data to the cloud server. Another hand implemented the device for loRa communication (data send rang up to 5km), here we need a loRa receiver to receive and sent sensor data to the cloud server. Wi-Fi and LoRa connective protocol of our smart agriculture device uses depend on different location & situation. Firmware & Application software implementation: Application Software: Here we used cloud server to store the data, and help of Rest API sent the command to the device. Device firmware has two measure function (i) Manual mode: In manual mode device will work, user pre set value of the sensor in device using web or smart app. (ii) Automatic Mode: In automatic mode device sent the sensor value to cloud server and machine learning algorithm take decision according the data. Conclusion Thus, the IoT agricultural applications are making it possible for ranchers and farmers to collect meaningful data. Large landowners and small farmers must understand the potential of IoT market for agriculture by installing smart technologies to increase competitiveness and sustainability in their productions. With the population growing rapidly, the demand can be successfully met if the ranchers, as well as small farmers, implement agricultural IoT solutions in a prosperous manner.

Hello guys, im a 17yo student that loves electronics and i started working on custom tv-b-gone based on arduino version with rechargeable battery and i needed pcbs for it. Firstly i ordered pcbs(on the left) that were $3 PER PIECE and then i found out for JLCPCB. They have amazing offer of 10pcs 10x10cm pcbs for $2!! I could fit 6 tv-b-gone boards on one 10x10cm pcb and multiply that by 10 and you get 60 pcbs for $2!!! When i first ordered i tough that its just a low quality board but when i received them in 2 weeks (which is really fast) i was SURPRISED by QUALITY for that LOW PRICE. First there was no shorts between any of the tracks. My design has really tight traces and they came out perfectly! Silk screen is also really good and vias are covered fully which gives boards nicer look. Panel by JLCPCB really made my job easier and it is also good, VCut is perfect, you just can snap the boards with hands and sand the sharp edges. They also make solder paste stencils which are helpful with pcbs with 95% of smd components and its also cheap, only $7 for big stainless steel stencil! Ordering is really simple. Go to https://jlcpcb.com/ and upload your gerber files in zip or rar format (there is also tutorial how to export gerber). If you want panel select "Yes" for "Panel By JLCPCB" and enter how many boards you want in a row and column. Im just really surprised by quality and looks of the pcbs. If you are interested in the project here are some video clips and soon there will be clip of assembling one with board from jlcpcb. https://jlcpcb.com/ https://jlcpcb.com/ https://jlcpcb.com/

The very first program you write when you start learning a new programming language is: "Hello World!". The program itself does nothing more than printing a “Hello World” text on the screen. So, how do we get our Arduino to display the "Hello World!"? In this video, I will be showing you how to get started with the small 0.91 (128x32) and 0.96 (128x64) I2C OLED displays. There are 100s of tutorials on the web explaining the same thing in different ways, but I couldn't find one that tells me all about the OLED display and how to use it in different scenarios. It took me some time to work it all out. So, I thought I should create a tutorial on what I have learned and combine all the features and ways the OLED displays can be used in our projects. Step 1: Things We Are Going to Learn Today In this video we will be talking about: - What is an OLED display? - Then we will have a closer look at the 0.91 (128x32) and 0.96 (128x64) I2C OLED displays - Next we will talk about installing the Adafruit Library to your Arduino IDE - Then we will connect NodeMCU and Arduino to an OLED display - Next we will have a look at the code and display some graphics and text on it - We will also talk about applying Custom Fonts and displaying Images - Then we will connect Multiple OLEDs to a micro-controller using I2C Multiplexer - Finally, we will talk about few common errors people make while using the OLED displays Step 2: Hardware Requirement For this tutorial we need: - A Breadboard - A 0.91" (128x32) and 0.96" (128x64) I2C OLED displays - Arduino UNO/NANO (whatever is handy) - NodeMCU - TCA9548A I2C multiplexer - Few Connecting Cables - and a USB cable to upload the code Step 3: What Is an OLED Display? OLED or organic light-emitting diode is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound (millions of small LED lights) that emits light in response to an electric current. OLEDs are used to create digital displays in devices such as television screens, computer monitors, portable systems such as mobile phones, hand-held game consoles and PDAs. An OLED display works without a backlight because it emits visible light. There are many types of OLED displays available in the market based on their - Sizes - Color - Brands - Protocol - SPI (Serial Peripheral Interface) or I2C - Passive-matrix (PMOLED) or active-matrix (AMOLED) control scheme In this tutorial, I am going to talk about connecting the blue color 0.91 (128x32 OLED) and 0.96 (128x64 OLED) I2C OLDE displays to an Arduino NANO and NodeMCU. I2C bus technology uses only 2 pins of the MCU so we have heaps available for other sensors. Step 4: Closer Look Lets have a closer at these two displays. At the back of these displays there are heaps of SMD capacitors and resistors soldered on-board; but, since its an I2C device we only care about these 2 pins (SCL and SDA) The display connects to Arduino using only four wires – two for power (VCC and GND) and two for data (serial clock SCL and serial data SDA), making the wiring very simple. The data connection is I2C (I²C, IIC or Inter-Integrated Circuit) and this interface is also called TWI (Two Wire Interface). - The on-board pins can be in different order, so always triple check before hooking it up to your project. - Operation voltage is between 3v to 5v but, it is best to use the guidance from the manufacturer's datasheet. - Sometimes we need to use 2 displays in our projects. So, how can we achieve this? The trick is to have a configurable address on your display. This unit has a configurable address between 0x78 and 0x7A. Just by unsoldering the 0Ohm resistor from one side and hoking it up to the other side or just by putting a global solder we can change the address. We will talk about it in depth when we hook up multiple displays to an Arduino in the later section of this tutorial. In picture these displays look very big. But, practically speaking they are tiny. They are made of 128 x 32/64 individual OLED pixels and do not require any back-light. Just have a look at this and see how small it is. Even though they are small they can be very useful in any electronic projects. Step 5: Library There are several libraries available to control these displays. In past I have used the "u8glib library" but I find the AdaFruit library very easy to understand and use in our projects. So, I am going to use the AdaFruit library in this tutorial. To control the OLED display you’ll need the "adafruit_GFX.h" library and the "adafruit_SSD1306.h" library. There are two ways you can download and install the library to your Arduino IDE. Method 1 Go to the "Library manager" and search "adafruit_SSD1306" and "adafruit_gfx" Select the latest version and hit the Install button. Once installed you can use these libraries in your program. Method 2 These two libraries can be also be downloaded from github (you need both): I will provide the links in the description below. The display library: https://github.com/adafruit/Adafruit_SSD1306 The GFX library: https://github.com/adafruit/Adafruit-GFX-Library Once downloaded, copy the Adafruit_SSD1306-master folder from the downloaded zipped file into the Arduino libraries folder. This folder is usually found at Documents > Arduino > libraries on Windows systems. On Linux it is usually found at home folder > Arduino > libraries. Finally in the Arduino library folder, rename the Adafruit_SSD1306-master folder to Adafruit_SSD1306. Even if you don’t rename that’s fine. Now, lets have a look at the "Adafruit_SSD1306.h" file Two things we need to know in this library: 1. If you want to use the smaller display use the default 128_32 otherwise for the bigger display comment the 128_32 and uncomment the 128_64 2. If you have soldered the 0x7A Address on the board (which we will talk about later) then use the 7 bit 0x3D address for the bigger displays, otherwise use the default 0x3C address. For the smaller displays the address is 0x3C. Step 6: Wiring 128 X 64/32 OLEDs Lets start by connecting the NodeMCU to the display. The first and most important thing to note is that some of the displays may have the GND and VCC power pins swapped around. Check your display to make sure that it is the same as the image. If the pins are swapped, make sure to change the connections to the Arduino or NodeMCU. - NodeMCU OLED Wiring OLED VCC – NodeMCU 3.3V OLED GND – NodeMCU GND OLED SCL – NodeMCU D1 OLED SDA – NodeMCU D2 - Arduino Uno OLED Wiring OLED VCC – Arduino 5V OLED GND – Arduino GND OLED SCL – Arduino Uno A5 OLED SDA – Arduino Uno A4 - Arduino MEGA 2560 OLED Wiring OLED VCC – Arduino 5V OLED GND – Arduino GND OLED SCL – Arduino MEGA 2560 pin 21 OLED SDA – Arduino MEGA 2560 pin 20 Step 7: Code Adafruit library comes with really good examples for both 128x32 and 128x64 displays. The Library is located under File > Examples > Adafruit SSD1306 > and then the display type in the Arduino IDE. We are going to use the 128x32 I2C example and will modify it to work with both 128x64 and 128x32 displays fist by hooking it up to an Arduino and then to a NodeMCU board. The code starts by including both the Adafruit libraries. In this tutorial I am going to stress on only those parts of the code which are necessary for us to load on both boards and displays. If you want to know more about the code please drop a comment on my blog or in the comments section below and I endeavour to get back to you. - First we are going to load the code to an Arduino Nano connected to a 128x32 display. We can use the code as is without any modifications. 128x32 uses 0x3C address so this bit looks all good here, lets double check the header library, yes its also using the 0x3C address and the display type is 128x32. - Now lets connect the 128x64 display. As we know it uses the 0x3C address by default so we don't need to update the address in either the code or the library. We just need we need to comment the 128_32 and uncomment the 128_64 in the header library and change the LCDHEIGHT to 64 in our code. - Now to run the same code on a NodeMCU we need to change one more line in our code. The "#define OLED_RESET 4" > "#define OLED_RESET LED_BUILTIN" rest of the code is same as Arduino Pretty much to display anything we first need to clear the previous screen using display.clearDisplay(); // Clear the buffer Then draw the object testdrawline(); // Draw a line Show it on the hardware display.display(); // Make them visible on the display hardware! Wait for some time before displaying the next item. delay(2000); // Wait for 2 seconds In this example we are displaying few items like text, lines, circles, scrolling text, triangles and more. Go ahead and use your imagination and display whatever you want on these tiny displays. Attachments Libraries.zip Download NodeMCU.zip Download Step 8: Customizing Text & Adding Images Sometimes your code needs to display custom fonts and images. If you are very good in bit mapping then you just need to create a byte arrays by turning on or off the tiny LEDs of the display to create custom fonts and images. However, I am not very good in doing these mappings and don't want to spend hours creating the bit map tables. So, what are my options? I generally use two websites to generate custom fonts and images. The links are provided in the description below. Custom Fonts ------------ Go to the font converter website, select the font family, style, size, Library Version as "Adafruit GFX Font" and then hit the "Create" button. On the right hand side of this page you can see how your font is going to look like on the actual display. Based on your selection the webpage generates the fonts header file. Create a file called "modified_font.h" in the same folder where your code is and copy and save the generated code into it. Then you just need to include the header file in your code to use the custom font. #include "modified_font.h" Then, you just need to set the font before displaying the text to apply the custom font to it. display.setFont(&Your_Fonts_Name); You can get the name of the font from the header file you just added to your project. Thats it, easy. Memory is always a concern while using custom fonts, so always consider the bytes that will be consumed by the memory. Just remember Arduino UNO has only 32K of memory. Custom Images ------------- To display a bitmap image on your screen you first need to create a 128 x 64/32 sized image. I am using the good old "MS Paint" to create a 128 x 64 bitmap image which I will then upload to this image converter website. The website converts images into byte-strings, which can be used with Arduino and OLED displays. Start by uploading the image to the website. Then put a check on the "Invert image colors" check-box and change the "Output code format" to "Arduino Code" next select the orientation and hit the "Generate Code" button to generate the byte array. The "Preview" section shows you how your image will look like on the actual display. I have included the code along with this tutorial which you can use to display your images. You just need to replace the array in my code with the one you just generated and then load it to your Arduino. Attachments Custom_Font.zip Download Custom_Image.zip Download Step 9: Connecting 2 Displays Connecting two 128 x 64 displays to your project is easy. You just need to unsolder the 0Ohm resistor from 0x78 address and put it on 0x7A and then use the 0x3D address in your code instead of the default 0x3C. You must be wondering why we are using the 0x3C and 0x3D address and not the actual 0x78 and 0x7A. Arduino accepts 7-bit address and not the 8-bit hardware addresses. So, we first need to convert the 8-bit address to binary, and then chop off the least significant bit to get the 7 bits. Then convert the 7 bits to HEX to get the 0x3C or 0x3D addresses which you enter in your code. First, initialize the display by giving it a unique name: Adafruit_SSD1306 display1(OLED_REST); Adafruit_SSD1306 display2(OLED_REST); Then in your code use the display 1 and display 2 to call the begin statements with the device addresses in them: display1.begin(SSD1306_SWITCHCAPVCC, 0x3C); // display 1 op address 0x3C display2.begin(SSD1306_SWITCHCAPVCC, 0x3D); // display 2 op address 0x3D That's it, you can now go ahead and do whatever you want using either Display 1 or Display 2 in the rest of your code. I have provided an example with this tutorial. Wiring is exactly the same as what we have done before, pretty much you just need to add another display to the same I2C pins of either the Arduino or NodeMCU. Based on the addresses, the MCU then sends the data on the I2C data line. Attachments Two_OLEDs.zip Download Step 10: Connecting More Than 2 Displays 3 More Images Now, what if you want to hook up more than 2 displays? Arduino has limited number of pins and hence you cannot have more than a certain amount of shields attached to it. Moreover, it has only one pair of I2C buses. So, how can we attach more than 2 I2C displays to an Arduino? The trick is to use a TCA9548 Multiplexer. TCA9548 allows a single micro-controller to communicate with up to '64 sensors' all with the same or different I2C address by assigning a unique channel to each sensor slave sub-bus. When we talk about sending data over 2 wires to multiple devices we then need a way to address them. Its same as the postman coming on a single road and dropping the mail packets to different houses because they have different addresses written on them. The Multiplexer connects to 3V3, GND, SDA and SCL lines of the micro-controller. The slave sensors are connected to one of eight SCL/SDA slave ports on the board. The channels are selected by sending the TCA9548A its I2C address (0x70 {default} - 0x77) followed by the channel number (0b00000001 - 0b10000000). You could have at the max 8 of these multiplexers connected together on 0x70-0x77 addresses in order to control 64 of the same I2C addressed parts. By connecting the three address bits A0, A1 and A2 to VIN you can get different combination of the addresses. I will explain this in-depth in my next tutorial on TCA9548A breakout board. For now, lets just hook up 8 OLEDs to this board and have a quick look at the code. Connection: VIN to 5V (or 3.3V) GND to ground SCL to I2C clock SDA to I2C data Then wire up the sensors to VIN, GND and use one of the SCn / SDn multiplexed buses Now, Int the code lets start by including the "Wire" library and by defining the multiplexers address. #include "Wire.h" #include #define MUX_Address 0x70 // TCA9548A Encoders address Then we need to select the port we want to communicate to and send the data on it using this function: void tcaselect(uint8_t i) { if (i > 7) return; Wire.beginTransmission(MUX_Address); Wire.write(1 << i); Wire.endTransmission(); } Next we will initialize the display in the setup section by calling "u8g.begin();" for each display attached to the MUX "tcaselect(i);" Once initialized, we can then do whatever we want just by calling the function "tcaselect(i);" where "i" is the value of the multiplexed bus and then sending the data and clock accordingly. Attachments I2C_Port_Scanner.zip Download Multipe_OLEDs.zip Download Step 11: Advantages and Disadvantages The image of an OLED is beautiful. However, OLEDs also have disadvantages. Because OLED screens contain organic material, their lifespan is shorter than LCD displays. Additionally, many OLED displays get burn-ins after showing the same image for a long time. After a burn-in, the image stays on the screen even after showing another image. So make sure you keep refreshing the screen every few seconds. Water can instantly damage the organic materials of these displays. Advantages No need for a backlight Displays are very thin and lightweight Low power consumption Viewing angles are wider than LCDs Brightness and contrast are great High speed and have low response time Deep black color Disadvantages Costly technology Short lifecycle OLEDS are more likely to burn-in Water damage Step 12: Common Errors To conclude the tutorial lets talk about few common errors people make while using these displays: - Always triple check the pins before using it in your project - Pick up the right library address in the header file and in your code #define SSD1306_I2C_ADDRESS 0x3C // in Adafruit_SSD1306.h and display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // in your code If the address is wrong the OLED will not display anything - The display size must be changed in the driver before it can be used. If it is not changed you will get an error message when attempting to verify the code #error ("Height incorrect, please fix Adafruit_SSD1306.h!"); - If using NodeMCU make sure you replace the OLED_RESET from 4 to LED_BUILTIN #define OLED_RESET LED_BUILTIN I have scene people making all sorts of things using this OLED display. Some have even made video games and all. I am really not interested in making a video game using this tiny display. However, I will now leave you to explore your imaginations and come out with amazing ideas. - Blog: http://diyfactory007.blogspot.com.au - Add Image: http://javl.github.io/image2cpp/ - Custom Text: http://oleddisplay.squix.ch/#/home - Adafruit display library: https://github.com/adafruit/Adafruit_SSD1306 - Adafruit GFX library: https://github.com/adafruit/Adafruit-GFX-Library - u8glib library: https://code.google.com/archive/p/u8glib/ or https://github.com/olikraus/u8glib If you want to use the smaller display use the default 128_32 otherwise for the bigger display comment the 128_32 and uncomment the 128X64 NO_ACK in your code (just uncomment the type of screen you are using) (fonts are in the fonts library) Attachments DataSheets.zip Download LCD-U8glib.zip Download OLED_Graphing.zip Download Schema.zip Download

Hi Everyone, In this tutorial I am going to show you how to charge a Lithium 18650 Cell using TP4056 chip utilizing the solar energy or simply the SUN. Wouldn’t it be really cool if you can charge your mobile phones battery using the sun instead of a USB charger. You can also use this project as a DIY portable power bank. The total cost of this project excluding the battery is just under $5. The battery will addup another $4 to $5 bucks. So the total cost of the project is some what around $10. All components are available on my website for sale for really good price, the link is in the description below. Step 1: Hardware Requirement For this project we need: - A 5v Solar Cell (make sure it is 5v and not anything less than that) - A general purpose circuit board - A 1N4007 High Voltage, High Current Rated Diode (for reverse voltage protection). This diode is rated at forward current of 1A with peak reverse voltage rating of 1000V. - Copper Wire - 2x PCB Screw Terminal Blocks - A 18650 Battery Holder - A 3.7V 18650 Battery - A TP4056 battery protection board (with or without the protection IC) - A 5 V power booster - Some connecting cables - and general soldering equipments Step 2: How the TP4056 Work Looking at this board we can see that it has the TP4056 chip along with few other components of our interest. There are two LEDs on board one red and one blue. The red one comes on when it is charging and the blue one comes on when the charging is done. Then there is this mini USB connector to charge the battery from an external USB charger. There are also these two points where you can solder your own charging unit. These points are marked as IN- and IN+ We will be utilizing these two point to power this board. The battery will be connected to these two point marked as BAT+ and BAT- (pretty mush self explanatory) The board requires an input voltage of 4.5 to 5.5v to charge the battery There are two versions of this board available in the market. One with battery discharge protection module and one without it. Both boards offer 1A charging current and then cut off when finished. Furthermore, the one with protection switches the load off when the battery voltage drops below 2.4V to protect the cell from running at too low (such as on a cloudy day) - and also protects against over-voltage and reverse polarity connection (it will usually destroy itself instead of the battery) however please check you have it connected correctly the first time. Step 3: Copper Legs These boards gets really hot so I will be soldering them a bit above the circuit board. To achieve this I am going to use a hard copper wire to make legs of the circuit board. I will then be sliding the unit on the legs and will solder them all together. I will put 4 copper wires to make 4 legs of this circuit board. You can also use - Male Breakable Pin Headers instead of the copper wire to achieve this. Step 4: Assembly The assembly is very simple. The solar cell is connected to the TP4056 battery charging board's IN+ and IN- respectively. A diode is inserted at the positive end for the reverse voltage protection. Then the BAT+ and BAT- of the board is connected to the +ve and -ve ends of the battery. (That all we need for charging the battery). Now to power an Arduino board we need to boost up the output to 5v. So, we are adding a 5v voltage booster to this circuit. Connect the -ve end of the battery to the IN- of the booster and +ve to IN+ by adding a switch in between. OK, now lets have a look at what I have made. - I have connected the booster board straight to the charger however I will recommend putting a SPDT switch there. So when the device is charging the battery its only charging and not getting used Solar cells are connected to the input of the lithium battery charger (TP4056), whose output is connected to the 18560 lithium battery. A 5V step-up voltage booster is also connected to the battery and is used to convert from 3.7V dc to 5V dc. Charging voltage is typically around 4.2V. Voltage booster's input ranges from 0.9 to 5.0V. So it will see around 3.7V at it's input when the battery is discharging, and 4.2V when it's recharging. The output of the booster to the rest of the circuit will keep it's 5V value. Step 5: Testing This project will be very helpful to power a remote data logger. As we know, the power supply is always a problem for a remote logger and most of the times there is no power outlet available. A situation like that forces you to use some batteries to power your circuit. But eventually, the battery will die. Question is do you want to go there and charge the battery? Our inexpensive solar charger project will be an excellent solution for a situation like this to power an Arduino board. This project can also solve the efficiency issue of Arduino when in sleep. Sleep saves battery, however, the sensors and power regulators (7805) will still consume battery in idle mode draining the battery. By charging the battery as we use it, we can solve our problem. Thanks again for watching this video! I hope it helps you. If you want to support me, you can subscribe to my channel and watch my other videos. Thanks, ca again in my next video. TP4056.pdf

Introduction --------------- Hi Everyone, This is my 1st Arduino's tutorial video. In this video i am going to show you how to use a LDR or Light Dependent resistor to turn on and off another circuit or a LED. Wouldn’t it be really cool if whenever a room gets dark, a light bulb automatically turns ON and eliminates the darkness? In this very simple project, I am focusing on eliminating darkness. You can even use this as an emergency lighting system. Step 1: Principle The LDR is a special type of resistor which allows a lower voltage to pass through it (high resistance) whenever its dark and higher voltages to pass (low resistance) whenever there is a high intensity of light. We are going to use a 10k resistor along with the LDR to create a voltage divider circuit. The varying resistance of the LDR is converted to a varying voltage that the analog pin of the Arduino will then be using in its logic. Step 2: Harware Reqirement For this very simple DIY Arduino project we need: - a breadboard - an arduino uno/nano (whatever is handy) - LED (Light Emitting Diode) - LDR (Photoresistor) - A 10K Resistor for creating the voltage divider and a 220ohm resistor for the LED - Few breadboard friendly connecting wires - and a USB cable to upload the code to the Arduino Step 3: Assembly - Connect the 3.3v output of the Arduino to the positive rail of the breadboard - Connect the ground to the negative rail of the breadboard - Place the LDR on the breadboard - Attach the 10K resistor to one of the legs of the LDR - Connect the A0 pin of the Arduino to the same column where the LDR and resistor is connected (Since the LDR gives out an analog voltage, it is connected to the analog input pin on the Arduino. The Arduino, with its built-in ADC (Analog to Digital Converter), then converts the analog voltage from 0-5V into a digital value in the range of 0-1023). - Now connect the other end of the 10K resistor to the negative rail - And the the second (free) leg of the LDR to the positive rail Pretty much this is what we need for the light sensing. Basic circuits like this can be done without an Arduino aswell. However, if you want to log the values and use it to create charts, run other logics etc. I will recomend an Arduino or ESP8266 or may be a ESP32 for this. Now, as we want our circuit to do something in the real world other than just displaying the values on the computer screen we will be attaching a LED to the circuit. The LED will turn on when its dark and will go off when its bright. To achieve this we will: - Place the LED on the breadboard - Connect the 220ohm resistor to the long leg (+ve) of the LED - Then we will connect the other leg of the resistor to pin number 13 (digital pin) of the Arduino - and the shorter leg of the LED to the negative rail of the breadboard Step 4: The Code const int ledPin = 13; const int ldrPin = A0; void setup() { Serial.begin(9600); pinMode(ledPin, OUTPUT); pinMode(ldrPin, INPUT); } void loop() { int ldrStatus = analogRead(ldrPin); if (ldrStatus <= 200) { digitalWrite(ledPin, HIGH); Serial.print("Its DARK, Turn on the LED : "); Serial.println(ldrStatus); } else { digitalWrite(ledPin, LOW); Serial.print("Its BRIGHT, Turn off the LED : "); Serial.println(ldrStatus); } } Thanks again for watching this video! I hope it helps you. If you want to support me, you can subscribe to my channel and watch my other videos. Thanks, ca again in my next Instructable.

Hi,I have created a isolated version of the common USB - UART converter for programming the Arduino mini.It have all the communication pins isolated: DTR, TX, RX and also CTS.This little board can be very useful if you are working on some projects and worrying to damage a USB port because of ground loop or a short circuit with the main power supply.Here our campain: https://www.kickstarter.com/projects/1351830006/isolated-usb-to-uart-converter-for-arduino-pro-min?ref=user_menuWe also made a short video: https://www.youtube.com/watch?v=ReD4d7x2PaoThanks!