The Kynix Blog

IntroductionThe Raspberry Pi is a small and powerful computer that you can use to learn programming through fun, practical projects. It is designed for encouraging people in computing and creating easier access to computing education. Pi is a microcomputer and its size is like a credit card. Its system is based on Linux and has all functions such as video and audio. With the release of Windows 10 IoT, we will also be able to use the Raspberry Pi on Windows.Raspberry Pi - All You Need To KnowCatalogIntroductionⅠ Who Invented the Raspberry Pi?Ⅱ Different Pi Versions2.1 Early Stage2.2 Pi Model B vs Pi Model B+2.3 Pi 22.4 Pi 2 Model B vs Pi Model B2.5 Pi 3 Model B2.6 Pi 4 Model B vs Pi 3 Model B+2.7 Pi 4 Model B Rev1.2 (8GB RAM Version)Ⅲ What can I do with Raspberry Pi?Ⅳ Raspberry Pi Programming Language4.1 Python4.2 C Language4.3 Java/BlueJ4.4 PERL4.5 ScratchⅤ Guide for Beginners: Use Raspberry Pi to Control LED Lights5.1 Model Selection5.2 Accessories5.3 Electronic Components5.4 System Installation5.5 SSH Login In5.6 Install Node5.7 Light LED5.8 LED Control Script5.9 HTTP ServerⅥ FAQⅠ Who Invented the Raspberry Pi?The Raspberry Pi was developed by the Raspberry Pi Foundation, an British charity. In March 2012, Eben Upton of the University of Cambridge officially launched the world’s smallest desktop computer, also known as a card computer, which has all the basic functions of a computer. This is Raspberry Pi. The purpose of this foundation is to promote the education of computer science and related subjects in schools and make computers interesting. The foundation expects that this computer will continue to be developed and applied to more fields in the world.The early concept of Raspberry Pi in 2006 was based on ATmega644 microcontroller. It is an ARM-based microcomputer motherboard, with SD/MicroSD card as the memory hard disk. There are 1/2/4 USB ports and a 10/100 Ethernet port around the card motherboard (type A does not have a network port), which can be connected keyboard, mouse and network cable, as well as a TV output interface for video analog signals and an HDMI high-definition video output interface. All the above components are integrated on a motherboard that is only slightly larger than a credit card. It has all the basic functions of a PC and only needs to be connected to the TV. And the keyboard can perform many functions such as spreadsheets, word processing, games, high-definition video and so on.The Raspberry Pi is produced through three companies with production licenses Element 14/Premier Farnell, RS Components and Egoman. The Raspberry Pi Foundation provides ARM-based distributions of Debian and Arch Linux for the public to download. It is also planned to provide support for Python as the main programming language, support for programming languages such as Java, BBC BASIC (via RISC OS image or "Brandy Basic" clone of Linux), C and Perl. Ⅱ Different Pi Versions2.1 Early StageIn the early days of the Raspberry Pi, there were two types, model A and model B. The main differences between them.Model A: 1 USB, no wired network interface, power 2.5W, 500mA, 256MB RAM.Model B: 2 USB, support wired network, power 3.5W, 700mA, 512MB RAM. In addition, the Raspberry Pi B model provides a computer board, power supply, keyboard, case or connection, but no RAM.In July and November 2014, the Raspberry Pi launched two models, B+ and A+, respectively. The main difference: Model A has no network interface, so the four USB ports are reduced to one. In addition, compared to Model B, Model A has reduced RAM capacity and has a smaller size. Model A can be said to be a cheap version of Model B, but the new model Model A also supports the same MicroSD card reader as Model B, 40-pin GPI port, Broadcom BCM2385 ARM11 processor, 256MB of memory and HDMI output port.In terms of configuration, model B+ uses the same BCM2835 chip and has 512MB RAM as model B. But compared with the previous generation, the B+ version has lower power consumption and more interfaces. Model B+ has increased the general-purpose input and output pins to 40, and the USB interface has also increased from 2 to 4. In addition, the power consumption of model B+ has been reduced by about 0.5W to 1W. The old SD card slot has been replaced with a more beautiful push-in microSD card slot, and the audio part uses a low-noise power supply. From the appearance point of view, the USB interface has been moved to the side of the motherboard, the composite video has been moved to the position of the 3.5mm audio port, and four independent mounting holes have been added.2.2 Pi Model B vs Pi Model B+In July 2014, the Pi Model B+ was released, still using the BCM2835 processor and the same system software as the previous generation. The RAM is still 512MB. But improvements have been made in the following key points:Figure 1. Raspberry Pi Model B1) More GPIO pins, a total of 40 pins. (The old version is 26 pins)2) 4 USB ports, and the hot swap and overcurrent protection have been improved.3) Use Micro SD slot not the SD.4) Lower power consumption, reducing power consumption by 0.5 to 1W.5) Audio optimization, the audio circuit uses a dedicated low-noise power supply.6) A more concise appearance, the B+ aligns the USB interface with the edge of the circuit board, removes the AV interface, and makes 4 fixing holes on the motherboard.2.3 Pi 2Figure 2. Raspberry Pi 2It is compared to previous generations.1) CPU single thread speed is increased by 1.5 times (up by 1.5x).2) Sunspider running score increased 4 times (4x faster).3) Multi-core video decoding rate based on NEON is increased by 20 times (20x faster).4) The overall multi-threaded CPU score of SysBench is 6 times (6x) that of the old version.2.4 Pi 2 Model B vs Pi Model BFigure 3. Raspberry Pi 2 Model B1) Equipped with a 900MHz quad-core ARM Cortex-A7 CPU, the performance is expected to be 6 times that of the previous B+ version.2) 1GB LPDDR2 SDRAM, twice the previous B+ version.3) Fully compatible with the Pi 1 generation.Since the CPU has been upgraded to the ARM Cortex-A7 series, the Raspberry Pi 2 will support the full range of ARM GNU/Linux distributions, including Ubuntu and even Windows 10.2.5 Pi 3 Model BFigure 4. Pi 3 Model BIn February 2016, the Raspberry Pi 3 Model B was released.1) Equipped with ARM Cortex-A53 1.2GHz 64-bit quad-core ARMv8 CPU.2) Add 802.11b/g/n wireless network card.3) Add low-power Bluetooth 4.1 adapter.4) The maximum drive current is increased to 2.5A.2.6 Pi 4 Model B vs Pi 3 Model B+Figure 5. Pi 4 Model B1) Equipped with Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz.2) VideoCore VI GPU, supports H.265 (4Kp60 decode), H.264 (1080p60 decode, 1080p30 encode), OpenGL ES 3.0 graphics.3) 1GB/2GB/4GB LPDDR4 memory.4) Full throughput Gigabit Ethernet (PCI-E channel).5) Support Bluetooth 5.0, BLE.6) Two USB 3.0 and two USB 2.0 ports.7) Dual micro HDMI output, support 4K resolution.8) The microSD storage system adds double data rate support.9) The previous version of the microUSB power supply interface has been changed to a USB Type-C interface in Pi 4 Model B.10) Increase driving current to 3A.2.7 Pi 4 Model B Rev1.2 (8GB RAM Version)On May 28, 2020, the Raspberry Pi Foundation announced the launch of the new Raspberry Pi 4B SKU, which is the 8GB RAM version. In order to make full use of it, Raspberry Pi also developed a dedicated 64-bit operating system based on Debian. In other respects, compared with the previous version, the power supply problem has been improved.Figure 6. Pi 4 Model B Rev1.2TMHW's test on the Pi 4B 8GB version shows that in terms of web performance, 7zip compression, and APP opening speed, 8GB does not even increase but decrease compared to 4GB. In addition, in a 32-bit system, the available RAM is 7.8GB, and a 64-bit system is reduced to 7.6GB. Ⅲ What can I do with Raspberry Pi?Just like any other desktop or portable computer running a Linux system, there are many things you can do with the Raspberry Pi. Of course, it is inevitable that there is a little difference. Ordinary computer motherboards rely on hard drives to store data, but for Raspberry Pi, SD cards are used as "hard drives", and you can also connect an external USB hard drive. Use Raspberry Pi to edit documents, browse the web, play games, etc. That is to say, it has a wide range of uses. So it is also a good choice to make it an excellent multimedia center. For example, the Pi can be used to play video, and it can even be powered through the USB interface of the TV.Figure 7. Raspberry Pi 4Ⅳ Raspberry Pi Programming Language4.1 PythonThe Pi in Raspberry Pi stands for Python. It has become one of the most famous programming languages used for coding. After all, it has been in continuous use for the past 20 years. Python has an easy-to-read syntax, which is very suitable for novices in the field. Now, it is widely used in modern applications, windows and online applications.4.2 C LanguageC is one of the most widely used computing languages in the world. It is widely used to create operating systems and even simple programming languages. As we all know, Raspberry Pi runs on Linux system, in fact, it is also written with C. Therefore, it is easily compatible with all Linux and Unix systems including Pi.4.3 Java/BlueJWhen it was first released, Java was hailed as the first language that allowed programmers to write code for any platform or operating system. Regardless of whether the platform is a windows machine or a Unix machine. You can run the program without rewriting the code. Once the code is compiled, it can be run anywhere. Java runs on the Raspberry Pi, but cannot be developed on it. By 2013, BlueJ was released. Once installed, it can be programmed in Java on the Raspberry Pi.4.4 PERLPERL is a high-level programming language. It can be conveniently used on the Raspberry Pi when building an automated process or analyzing and debugging its output. Perl has a better library and ecosystem. It is the default setting of Raspberry Pi. Through a simple meta-analysis of the quality of existing libraries, PERL can be updated to a better version, because the default library may be incomplete or of low quality.4.5 ScratchScratch is the second programming language that suitable for Raspberry Pi. Because this coding language is included with the Raspberry Pi kit. It is a visual programming tool. With it, you can create animations and games. The latest version allows programmers to control Raspberry Pi's GPIO (General Purpose Input and Output) pins. Ⅴ Guide for Beginners: Use Raspberry Pi to Control LED Lights5.1 Model SelectionRaspberry Pi is a tiny computer integrated on a circuit board. Currently, there are two latest (1) Raspberry Pi 3 Model B(2) Raspberry Pi zero (zero w)Although the latter is cheap, it lacks a lot of interfaces (for example, only one USB port), the CPU and memory are relatively low-capacity, and the accessories are also few. Therefore, it is recommended to buy the third-generation B-type. But zero w can also meet most of the needs.5.2 AccessoriesThe Raspberry Pi itself is just a host. If you want to run it, there must be accessories.(1) Power SupplyA mobile phone charger with a Micro USB interface can be used as a power source, but the output must be 5V voltage and at least 2A current. It’s okay to use a power bank as a power source.Figure 8. Micro USB(2) Micro SD CardThe Raspberry Pi does not have a hard drive, and the Micro SD card is the hard drive. The minimum capacity is 8G, and 16G and 32G cards are recommended.Figure 9. Micro SD(3) DisplayThe Raspberry Pi has HDMI output, and the display must have it. If there is an HDMI to VGA adapter cable, then the VGA monitor will also work. Here I use a 7-inch LCD monitor.Figure 10. LCDHowever, the monitor is only needed when installing the system, and SSH can be used to log in later.(4) Wireless Keyboard and MousePi has built-in Bluetooth, so USB or Bluetooth wireless keyboard and mouse can be used.Figure 11. Wireless Keyboard and MouseJust like the monitor, if the Pi has been installed with the system and only used as a server, the wireless keyboard and mouse are not required.5.3 Electronic ComponentsIn addition to accessories, the following experiment also requires some electronic components.(1) Breadboard (one piece)(2) Electrical Cable (several)Note that the connection cable must be female to male.Figure 12. Electrical Cable (Female)Figure 13. Electrical Cable (Male)In addition, it is best to prepare some cables with male to male.(3) LED Diodes (several)(4) 270Ω Resistors (several)5.4 System InstallationIf the merchant has already installed the system, you can skip this step, otherwise you need to install the operating system.The official operating system is Raspbian, which is a customized version of the Debian system.The official also provides an installer NOOBS. It is recommended to install Raspbian through it, which is relatively simple.Download NOOBS:1) Format the Micro SD card into FAT format (operation guide).2) Unzip NOOBS.zip to the root directory of the Micro SD card.3) Insert the Micro SD into the slot at the bottom of the Raspberry Pi, turn on the power, and start the system.4) Under normal circumstances, follow the prompts on the screen and press Enter all the way to install the system.5.5 SSH Login InAfter installing the system, the Pi can access the Internet (Wifi or network cable). At this time, you need to check its LAN IP address, you can use the following command.    $ sudo ifconfigThen, change the system settings and turn on SSH login (default is forbidden).Then, login the Raspberry Pi from another computer SSH. The following command is executed on another computer in the LAN.    $ ssh pi@192.168.1.5In the above code, 192.168.1.5 is the address of my Raspberry Pi, so you need to replace it with yours. The default user of the Raspberry Pi is pi, and the initial password is raspberry. Under normal circumstances, you can log in to it. Then, you can perform various server operations, such as changing the password.    $ passwdThe following experiments need to add users to the gpio user group.    $ sudo adduser pi gpioThe above code means adding user pi to the gpio user group.5.6 Install NodeIn order to run Node scripts, Raspberry Pi must install Node. You can refer to this.    $ curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -    $ sudo apt install nodejsUnder normal circumstances, Node 8.x has been installed successfully.    $ node -v    v8.1.05.7 Light LEDPi provides a set of external IO interfaces, called GPIO (general-purpose input/output).Figure 15. GPIO PinsThe definition of its 40 pins is shown in the figure below.Figure 16. Raspberry Pi 40 PinsNote that the first pin (3.3V) in the upper left corner is a square, and the other pins are round. Turn the Raspberry Pi over, and you can see that one corner of the GPIO is square. In this way, you can confirm which pin eye is 3.3V.Through GPIO, the Pi can be connected with other electronic components. Next, according to Jonathan Perkin's article, connect LED diodes.Figure 17. Raspberry Pi BackA breadboard is needed here. In essence, a breadboard is just a few wires with many holes that can be connected to the wires.Figure 18. Connect with BreadboardThe + pole and the-pole are two vertical wires, the row marked with the numbers 1, 5, and 10 is a horizontal wire. The wires are not connected to each other, and the left and right halves of the breadboard are also not connected to each other.Then, connect the Raspberry Pi, breadboard, LED lights, and resistors according to the diagram below.Figure 19. Parts ConnectionIn the above figure, the red wire represents the positive electrode of the current, which is connected from the first pin (3.3V) of the GPIO to the breadboard. The black wire represents the negative electrode of the current, which is connected from the 6th pin (ground) of the third row of the breadboard. It does not matter which hole they connect to the breadboard, but it must be ensured that a complete circuit can be formed (the direction of the arrow in the figure above). Note that LED diodes also have positive and negative poles, with the long pin indicating the positive pole and the short pin indicating the negative pole. The resistor has no positive and negative poles.After the connection is complete, turn on the power and the LED should light up.5.8 LED Control ScriptNext, we use the Node script to control the LED.First, unplug the positive wire from pin 1 (3.3V) and plug it into pin 11 of row 6 (GPIO 17 in the figure above). The current of this pin can be controlled by the script.Then, create a new experiment directory on the Pi, and install the Node module rpio that controls GPIO.    $ mkdir led-demo && cd led-demo    $ npm init -y    $ npm install -S rpioNext, create a new script led-on.js.    // led-on.jsvar rpio = require('rpio');    // Turn on pin 11 (GPIO17) as output    rpio.open(11, rpio.OUTPUT);    // Specify the output current of pin 11 (HIGH)    rpio.write(11, rpio.HIGH);Run this script and you can see the LED bulbs light up.    $ node led-on.jsCreate a new led-off.js script, just change one line (see here for the complete code).    // led-off.js    //...    // Designate Pin 11 to stop output current (LOW)    rpio.write(11, rpio.LOW);Run this script and the LED bulb should be off.    $ node led-off.jsWith these two scripts, it is easy to make the LED blink. Create a new led-blink.js script.    // led-blink.js    var rpio = require('rpio');    rpio.open(11, rpio.OUTPUT);    function blink() {      rpio.write(11, rpio.HIGH);      setTimeout(function ledoff() {        rpio.write(11, rpio.LOW);      }, 50);    }    setInterval(blink, 100);The above script makes the LED blink 10 times per second.    $ node led-blink.js5.9 HTTP ServerMany things can be done by controlling the LED, such as setting up an HTTP server. Whenever someone visits, the LED will blink.First, install a server module in the directory just now.    $ npm install -S serverThen, create a new script server.js.    // server.js    var server = require('server');    var { get } = server.router;    // ...    server({ port: 8080 }, [      get('/' ,  ctx => {        console.log('a request is coming...');        blink();      }),    ]);    console.log('server starts on 8080 port');Run this script.    $ node server.jsThen, open a command line terminal, access port 8080, and the LED will flash.    $ curl http://localhost:8080After reading the tutorial, you can try it yourself. For example, if you write a test case script, the LED will stay light as long as the test fails, or you can assemble an 8-bit adder. Ⅵ FAQ1. What is Raspberry Pi and how does it work?The Raspberry Pi is a tiny computer about the size of a deck of cards. It uses what's called a system on a chip, which integrates the CPU and GPU in a single integrated circuit, with the RAM, USB ports, and other components soldered onto the board for an all-in-one package.2. What is the Raspberry Pi used for?The Raspberry Pi is a low cost, credit-card sized computer that plugs into a computer monitor or TV, and uses a standard keyboard and mouse. It is a capable little device that enables people of all ages to explore computing, and to learn how to program in languages like Scratch and Python.3. Can Raspberry Pi replace PC?Of course, the Raspberry Pi can't replace most professional desktops, but in general, it can run almost all programming languages and frameworks, from Python to Fortran.4. What do I need to use a Raspberry Pi?What you will need:A Raspberry Pi computer with an SD card or micro SD card.A monitor with a cable (and, if needed, an HDMI adaptor)A USB keyboard and mouse.A power supply.Headphones or speakers (optional)An ethernet cable (optional)5. Which Raspberry Pi is best for beginners?Best Raspberry Pi Starter KitsCanaKit Raspberry Pi 3 B+ Starter Kit 32GB EVO+ Edition Premium Black Case.Vilros Raspberry Pi 3 B+ Complete Starter Kit with Clear Case and 16GB SD Card.Smraza Raspberry Pi 3 B+ Starter Kit, Compatible Pi 3 Model B Case, 16GB SD Card, 2.5 A Power Supply.6. What projects can you do with Raspberry Pi?Best Raspberry Pi Projects for 2021Google Enabled Magic Mirror.Solar-Powered Pi.Game Console.Remote-Controlled 3D Printer.Language Translator.Satellite Tracking Globe.PC Hardware Stats Monitor.Security Camera.7. Which is cheaper Arduino or Raspberry Pi?The two most popular among them are: Arduino and Raspberry Pi. Arduino is based on the ATmega family and has a relatively simple design and software structure. Raspberry Pi, basically is a single-board computer.8. Which programming language is used for Raspberry Pi?Python. One of the most widely used programming languages on the Raspberry Pi is none other than Python. Python has an easy, beginner-friendly syntax (arrangement of words, phrases, in sentences) and a wide adoption rate among the community, giving access to libraries, frameworks, and tools to help users get started.9. Can a Raspberry Pi run Windows?The Raspberry Pi 4 can handle Microsoft Edge, the calculator app, and more, all via the power of Windows 11. It can even run Minecraft, albeit in an undesirable state.10. Can you watch Netflix on Raspberry Pi?Although there are some Android images for the Raspberry Pi, Linux distributions (distros) for the Pi are more stable. And with newfound Widevine DRM support, the Raspberry Pi can comfortably stream Netflix, Hulu, Disney+, HBO Max, and Spotify.11. Can you hack with Raspberry Pi?The Raspberry Pi also runs Raspbian, the official OS of the Raspberry Pi. This Debian-based OS can also be used to learn basic Linux and hacking tools, although it requires much more customization before it's suitable for this.12. Which is better for beginners Arduino or Raspberry Pi?The Arduino board is much simpler to use in comparison to Raspberry Pi. The Arduino board can easily be interfaced with analog sensors and other electronic components using only a few lines of code. ... The coding in Arduino is also easier than Raspberry Pi, the latter requiring knowledge of Linux and its commands.13. How do I put codes into my Raspberry Pi?Open IDLE by selecting the Raspberry Pi logo in the top-left, and click Programming > Python 3 (IDLE). You should be presented with the Python interactive interpreter. To write a program, go to File > New File. Enter in your code.14. Can I run Android on Raspberry Pi?First Look: You Can Now Run Android 12 on Your Raspberry Pi 4 Computer. Even if your smartphone doesn't run Android 12 yet, you can now use Google's latest mobile operating system on a Raspberry Pi 4, 400 or CM4 computer.15. What is the advantage of Raspberry Pi over Arduino?Raspberry Pi is 40 times faster than Arduino, with PI, you can send mails, listen music, play videos, run internet etc. Also as we have stated earlier that it has memory, processor, USB ports, Ethernet port etc. and it doesn't require external hardwares for most of the functions.16. How do I use Raspberry Pi with IOT?Connecting the Raspberry Pi to the Outside World - GPIO PinsTo connect the GPIO to external sensors, you can: Connect the sensors directly to the GPIO pins using jumper wires. Connect the GPIO pins to a ribbon cable, which in turn connects it to a breadboard.17. Which is more powerful Raspberry Pi or Arduino?Given those differences you might think a Raspberry Pi is so much more powerful and capable than Arduino, so you should use that. ... Raspberry Pi has 8. Individual I/O pins in Arduino can drive 40mA while Raspberry Pi GPIO pins can each drive a maximum of 16mA18. How many devices can connect to Raspberry Pi?There is a limit of 30 simultaneously connected devices on Pi 4 - the hardware supports 32 device address slots but one address is kept free for unconfigured devices and one address is reserved by the internal USB2. 0 hub for the USB2. 0 ports.19. How many pins are there on Raspberry Pi board?40 pinsOf the 40 pins, 26 are GPIO pins and the others are power or ground pins (plus two ID EEPROM pins, which you should not play with unless you know your stuff!).20. How much RAM does the Raspberry Pi has?The Raspberry Pi 2 has 1 GB of RAM. The Raspberry Pi 3 has 1 GB of RAM in the B and B+ models, and 512 MB of RAM in the A+ model. The Raspberry Pi Zero and Zero W have 512 MB of RAM. The Raspberry Pi 4 is available with 2, 4 or 8 GB of RAM.21. Why is Raspberry Pi 4 so expensive?Due to supply shortages, the Raspberry Pi Foundation can no longer afford to produce them at that price, and so have had to increase the price to $45. ... To help mitigate this price increase, the company is reintroducing the 1GB version of the RPi 4, which was retired in February 2020.22. How do you do Pi in Google Sheets?Creating the PI Symbol with the CHAR FunctionThe amazing CHAR function, which converts numbers into characters per the Unicode table, can output the symbol for pi in your Google Sheet.

ⅠIntroduction This project mainly introduces how to DIY a Simple Audio Player with  Amplifier LM386 . But before this project, it is very essential to know some basics of LM386. Therefore, the first of this article is about LM386 audio amplifiers and the second part we will have a look at the practical appliance of Simple Audio Player with Amplifier LM386. Catalog ⅠIntroduction Ⅱ Amplifier LM386 Related Video: Ⅲ LM386 Basics 3.1 LM386 Datasheet 3.2 LM386 Pinout 3.3 LM386 Features Ⅳ  Project Introduction 4.1 Hardware Required 4.2 Getting Ready with Your WAV Audio Files: 4.3 Circuit 4.4 Code 4.5 Working of this Arduino Music Player: Ⅴ FAQ How to make an LM386 audio amplifier circuit Amplifier LM386 Video Description: In this Video, We will explore how to use the popular LM386 class AB audio amplifier IC to build a simple mono 1 watt audio amplifier.  Ⅲ LM386 Basics Despite the fact that LM386 audio amplifiers are quite old. They do, however, have a lot of useful information. Assume your audio player has poor sound quality. You want to boost the volume. They are a good option. Because of the low voltage supply and the fact that it works well with a battery.   3.1 LM386 Datasheet You completed an audio circuit  . However, the sound is too faint. Many people use the LM386 to boost the sound to a speaker. The LM386 is a low-power audio amplifier. Also, you should be able to work with a battery,  It has a similar shape to  IC-741  and DIP-8. So, small and simple. Even if it's small, it makes a big sound. But...better. it's If you have previously read the LM386 Datasheet.   3.2 LM386 Pinout Figure1:pinout In DIP-8, we frequently use the LM386. There are only a few pin connections. Other packets are also the same. For example, SOP-8, TSSOP-8, and so on.   3.3 LM386 Features   Ⅳ  Project Introduction Including sounds or music in our project will always make it look and sound much more appealing. If you're working with an  Arduino  and have a lot of free spins, you can easily add sound effects to your project by purchasing an extra SD card module and a standard speaker. In this article, I'll show you how to play music and add sound effects with your  Arduino board, as well as introduce the IC LM386 Amplifier  , which we'll use in this process. We will play the.wav music files stored on an SD card in this project. The Arduino will be programmed to read these.wav files and play the audio on a speak through an LM386 Audio amplifier.   Figure2: Project     4.1 Hardware Required Arduino Due Board8-ohm speaker or headphonesArduino shield with an SD card with cs CS 4 (like the Ethernet shield)Components to build an external audio amplifierLM386 (low power audio amplifier)10 kohm potentiometer10 ohm resistor2 x 10 µF capacitor0.05 µF (or 0.1 µF) capacitor250 µF capacitor   4.2 Getting Ready with Your WAV Audio Files: The audio file to be stored on the SD card must be in.wav format and have 44100 Hz, 16-bit stereo quality. We need audio files in.wav format to play sounds from an SD card using Arduino because the Arduino Board can only play audio files in a specific format, which is wav format. There are many mp3 shields available for use with Arduino to create an Arduino mp3 player. Alternatively, to play mp3 files in Arduino, there are websites that will convert any audio file on your computer into that specific WAV file.   4.3 Circuit The shield is placed on top of the Due, and a micro-SD card is inserted into the slot. The card's root directory contains a.wav file called "test.wav." For a quick test, connect a pair of headphones to the ground and DAC0 while keeping the polarity in mind. To add a speaker to the board, connect an amplification circuit between the DAC0 pin and the speaker. The amplification circuit will boost the speaker's volume,  There are numerous audio amplifiers available, with the LM386 being one of the most common. The following scheme demonstrates how to construct the circuit using the LM386 and a variety of components. You can power the LM386 by connecting the Vs pin to various voltage sources, such as the +5 V on the Arduino Due's 5V pin or an external 9V  battery,  The capacitor is connected to pins 1 and 8 of the LM386 provides the amplifier's gain. The gain is set to 200 with the 10 F capacitor, and 50 without the capacitor. The volume of the amplifier can be adjusted using the potentiometer. Caution: Do not connect the speaker directly to the Arduino Due's pins.   Figure3 : Circuit   Figure4: LM386 mounting on breadboard   4.4 Code   4.5 Working of this Arduino Music Player: Simply press the button connected to pin 2 after programming your Arduino, and your Arduino will play the first song (saved as 1.wav) for you. You can now press the button again to change your track to the next song, 2.wav. Similarly, you can listen to all four songs. You can also play/pause the song by pressing the pin 3 button. Press it once to pause the song and once more to resume it from where it left off. Watch the video below to see the entire process in action (or maybe to relax with some songs). I hope you had a good time with the project. It is now up to your imagination to incorporate them into your projects. You can create a speaking clock, voice assistant, talking robot, voice alert security system, and many other things.   Ⅴ FAQ 1. How many watts is LM386? 700mW, mono, 5- to 18-V, analog input Class-AB audio amplifier. 2. How do you calculate LM386 gain? Voltage Gain Analysis: Without any external components, it has a gain of Gv = 2x15K/(150+1350) = 20 (26 dB). With a capacitor (or shortcutting) between pins 1 and 8 , it has a gain of Gv = 2x15K/150 =200 (46dB). 3. Is LM386 any good? The LM386 is a well-designed, basic workhorse that does a decent job when its hooves are kept clean and it's well-fed. Aside from having a slow op-amp stage by today's standards, it has decent performance. It can also sound horrible if you neglect it. 4. What is an audio amplifier circuit? The circuit of the audio amplifier consists of a transistor a device to apply the input signals and a speaker at the output. The transistors are connected based on the necessity. The important factors that need to be considered while designing a audio amplifier is gain,noise, frequency response and distortion. 5. Which amplifier can be used for audio amplifier? An audio power amplifier (or power amp) is an electronic amplifier that amplifies low-power electronic audio signals such as the signal from radio receiver or electric guitar pickup to a level that is high enough for driving loudspeakers or headphones. 6. What is the need of power amplifier? The function of a power amplifier is to raise the power level of input signal. It is required to deliver a large amount of power and has to handle large current. The characteristics of a power amplifier are as follows − The base of transistor is made thicken to handle large currents.

IntroductionAs the most popular open-source hardware in the world, Arduino is not only an excellent hardware development platform, but also a trend in hardware development. Its simple development method makes developers pay more attention to creativity and realization, complete their own projects and get experiments faster, which greatly saves the cost of learning and shortens the development cycle. There are too many want to say, in short, arduino provides a lot of convenience for many electronics enthusiasts and creators, and also provides a platform for sharing their results. So what exactly is it? How does it work?CatalogIntroductionⅠ What is Arduino?Ⅱ Who Make the Arduino?Ⅲ Why Use Arduino?Ⅳ What Does Arduino Have?Ⅴ Arduino Programming LanguageⅥ Arduino Basic ArchitectureⅦ Copyright and PaymentⅧ Simple Arduino Projects8.1 Video Demonstration8.2 Examples and Programming CodesⅨ FAQⅠ What is Arduino?Arduino is a tool that can be used to sense and control the physical world more than your desktop computer. It consists of an open source-computer platform based on a simple single-chip microcomputer, and a development environment for writing programs for the Arduino board.Arduino can be used to develop interactive products. For example, it can read a large number of switches and sensor signals, and can control a variety of lights, motors, and other physical devices. The Arduino project can be a standalone project, or it can communicate with programs running on your computer (for example: Flash, Processing, MaxMSP) at runtime. You can choose to manually assemble the Arduino board yourself or buy a productthe, because open-source IDE can be downloaded for free.The Arduino programming language seems to be correspondingly connected to a physical computing platform, which is based on a programming environment that handles multimedia.Learn Arduino in 15 MinutesⅡ Who Make the Arduino?Massimo Banzi was a teacher at a high-tech design school in Ivrea, Italy. His students often complain about not being able to find cheap and easy-to-use microcontrollers. In the winter of 2005, Massimo Banzi discussed this problem with David Cuartielles. He is a Spanish chip engineer who was a visiting scholar in this school at the time. The two decided to design their own circuit boards and introduced David Mellis (Banzi student) to design a programming language for the circuit boards. Two days later, David Mellis wrote the code. After another three days, the circuit board was completed. Massimo Banzi likes to go to a bar called di Re Arduino, which was named after the Italian king Arduin 1,000 years ago. To commemorate this place, he named this circuit board Arduino.Figure 1. The Making Arduino Core Team Ⅲ Why Use Arduino?There are many single-chip microcomputers and their platforms that are suitable for the design of interactive systems. For example: Parallax Basic Stamp, Netmedia's BX-24, Phidgets, MIT's Handyboard and others provide similar functions. With all these tools, you don't need to care about the cumbersome details of MCU programming. Arduino provides you a set of easy-to-use toolkits. Arduino also simplifies the process of working with a single-chip microcomputer, but compared with other systems, it has many advantages in many places. In fact, it is especially suitable for teachers, students and some amateurs:0️⃣Cheap1️⃣Cross-platform2️⃣Simple programming environment3️⃣The software is open-source and expandable.4️⃣Hardware is open-source and expandable. Ⅳ What Does Arduino Have?At the beginning of Arduino development, its application environment was clarified, and an open-source platform was designed to facilitate its secondary development. The main features of Arduino are as follows:1) Open-source circuit diagram design. The program development interface is free to download, or you can modify it according to your needs. Arduino carries low-priced microcontrollers (ATmega8 or ATmega128). It can be powered by a USB interface, no external power supply, and an external 9VDC input can also be used.2) Support ISP online programming, making the Bootloader firmware into the chip. The Arduino controller contains the Bootloader program, which is the first piece of code that runs after the system is powered on. It is like the program in the BIOS of the PC. It performs self-check after startup, configures the port, and so on. Of course, the microcontroller relies on programming the fuse. Set the startup from the boot area after power-on, and use this program to directly store the program sent from the serial port in the flash area. Therefore, when using the Arduino compilation environment to download the program, first reset the microcontroller and start the Boodoader program to guide the program sent from the serial port to be successfully written into the flash area. The flash can be programmed repeatedly, so it is very convenient to update the software. After having Bootloader, you can update the firmware through the serial port or USB to RS232 line.3) According to the official PCB and SCH circuit diagrams, the Arduino module can be simplified to complete independent micro-processing control.4) It can be easily connected with sensors and various electronic components, such as infrared, ultrasonic, thermistor, photoresistor, servo motor, etc.5) Support a variety of interactive programs, such as Flash, Max/MSP, VVVV, PurEDAta, C, Processin, etc.In terms of application, the use of Arduino can break through the interactive content of devices that can only use mouse, keyboard, CCD and other input devices in the past. For example, it can achieve single-player or multi-player game interaction more simply. The functional characteristics of Arduino make it more and more widely used. Ⅴ Arduino Programming LanguageUsually, the Arduino language we say refers to a collection of various application programming interfaces (APIs) provided by the Arduino core library files. Arduino uses C/C++ to write programs. Although C++ is compatible with C language, these are two languages. C language is a process-oriented programming language, and C++ is an object-oriented programming language. The early Arduino core library was written in C language, and later object-oriented ideas were introduced. At present, the latest Arduino core library is written in a mixture of C and C++.The Arduino language is a program framework that starts with setup() and loop() as the main body. setup() is used to initialize variables, pin modes, call library functions, etc. This function only runs once, and its function is similar to "main()" in C language. For the loop() function, the statements in the function are executed in a loop.Arduno language modularizes some parameter settings related to AVR microcontroller, including EEPROM, Ethernet, LED matrix, steering gear, stepping and TWI/I2C control library. It does not require the user to directly deal with the underlying system, which can improve the efficiency of application development. Ⅵ Arduino Basic ArchitectureThe Arduino system has also developed different versions based on different application environments. The "Arduino Duemilanove" version is used as an example to introduce the Arduino system. This version was developed in 2009 and is based on the atmega328 microcontroller board. During use, connect the computer with a USB cable or use a power adapter to power it.1) One 9V DC input provides external power output for the Arduino board, so that the Arduino control board has the ability to drive high-power external devices such as steering gear.2) One USB port used to connect the computer. The Arduino IDE uploads the control program written by the user to the control board, and at the same time, it can also supply power to the circuit board and drive low-power external devices through this port.3) 14 digital input/output terminals, among which ports 0 (RX) and 1 (TX) are respectively connected to the serial pins of the main control chip to receive and send TTL serial data. Among them, ports 2 and 3 can receive external signals to realize external interrupt function. Ports 3, 5, 6, 9, 10, 11 are used as PWM ports, which can be used for motor PWM speed regulation or music playback. Port 10 (SS), 11 (MOSI), 12 (MISO) and 13 (SCK) can provide SPI communication mode with the support of SPI module library. Port 13 is connected with an LED indicator, which can open and close with the change of the level on pin 13.4) 6 analog input/output ports, of which port 4 (SDA) and port 5 (SCL) can realize I2C communication.5) One 5V DC output and one 3.3V DC output, which can provide 3.3V and 5V DC power supplies for other circuits.6) One reset interface.The Arduino system is developed based on a single-chip microcomputer, and a large number of common and standard electronic components are used on it. The entire design, including hardware and software, is released in an open source manner. Therefore, the cost of procurement is relatively low. In various electronic production competitions, Arduino is used as a development platform for creative design of electronic artwork.Figure  2. Arduino Board Terminals🔺Arduino Hardware✔️There are many motherboard, such as:Arduino UnoArduino NanoArduino LilyPadArduino Mega 2560Arduino EthernetArduino DueArduino LeonardoArduinoYún✔️There are many expansion boards for Arduino, such as:Arduino GSM ShieldArduino Ethernet ShieldArduino WiFi ShieldArduino Wireless SD ShieldArduino USB Host ShieldArduino Motor ShieldArduino Wireless Proto ShieldArduino Proto Shield Ⅶ Copyright and PaymentIn order to maintain the open-source concept of the design, Arduino decided to adopt the Creative Commons license, which is a license similar to GPL that appears to protect open copyright activities. Because copyright law can regulate open-source software, but it is difficult to use it on hardware. Having this license, anyone is allowed to produce copies of circuit boards, redesign, and even sell copies of the original design. You don't need to pay royalties, or even get permission from the Arduino team. However, if you republish the reference design, you must sign the original Arduino team. In addition, if you adjust or modify the circuit board, your latest design must use the same or similar license to ensure that the new version of the Arduino circuit board will be free and open. In other words, only the name Arduino is reserved, and it is a trademark now. If someone wants to sell a circuit board under this name, they must pay a small trademark fee to the Arduino core development members. Ⅷ Simple Arduino Projects8.1 Video DemonstrationBasic Projects with Arduino8.2 Examples and Programming Codes🔺Water Lamp ControlInsert 6 LED lights on the breadboard, among which the long pins are assigned to the 6, 7, 8, 9, 10, 11 ports of arduino respectively, the short pins are all connected to the blue wire of the breadboard, and then one port of the blue wire is connected to the GND port of the arduino. Figure  3. Water Lamps ConnectionCode:void setup(){ pinMode(6,output);pinMode(7,output);pinMode(8,output);pinMode(9,output);pinMode(10,output);pinMode(11,output);}void loop(){digitalWrite(6, LOW);digitalWrite(7,HIGHT);delay(200);digitalWrite(7, LOW)；digitalWrite(8,HIGHT);delay(200);digitalWrite(8,LOW);digitalWrite(9,HIGHT);}🔺Using the Buzzer to Realize the AccordionThe buzzer is set according to different frequencies, so set the corresponding buzzer frequency based on the level of the switch interface.void setup(){pinMode(8,INPUT);  //switch setdigitalWrite(8, HIGH);pinMode(9,INPUT);digitalWrite(9, HIGH); piMode(10,INPUT);digitalWrite(10, HIGH); pinMode(11,OUTPUT) //light setpinMode(12, OUTPUT)pinMode(13,OUTPUT)}void loop(){if(digitalRead(8)==LOW){tone(7,2093);  //the buzzer frequency is set to 2093digitalWrite(11, HIGH);}else{notone(7);digitalWrite(11,LOW);}Repeat 2 switch values down;;; 🔺Breathing LightThe so-called breathing is relatively stable, so it cannot flicker and go off like a flashing LED. So analog output is used, and the current changes continuously.Figure  4. Breathing Light ConnectionCode:void setup(){pinMode(11,OUTPUT);  }void loop(){for(int i=0;i<30;i++){analogWrite(11,i);   //analog signal input, the range of i is [0,255];delay(10);}for(int j=29;j>0;j--){analogWrite(11,j);delay(10);}} Among them, the corresponding relationship between the analog signal voltage and the digital signal voltage:How is the analog signal realized to control the voltage within a range in a cycle?Figure  6. PWMAs shown in the figure, “on” belongs to 5V, and “off” belongs to 0V. In a time period, that is, when a pulse is sent, the duration of “on” in the previous figure is 25%, and the “off” is 75%. The voltage value calculated like this: v0=5*25%+0*75%=1.25(v). It can be simply understood like this. 🔺Breathing Water Lampvoid  setup(){pinMode(3, OUTPUT);pinMode(5, OUTPUT);pinMode(6, OUTPUT);pinMode(9, OUTPUT);pinMode(10, OUTPUT);pinMode(11, OUTPUT);}int  ports[6]=[3,5,6,9,10,11];int i=0，level=0; set loop(){ analogWrite(ports[i], level);delay(10);++level %=7;++i %=6;  i is incremented first, and then modulo 6, that is, i is always in the range of 0~5；}🔺Vibrating LEDPhotoresistor, resistor, LED are required;Connect one end of the photoresistor to 5V, the other end to the resistor, and the resistor to GND. Pull out a wire between the two and connect to analogIn;Figure  7. Vibrating LED ConnectionCode:void setup(){Setrial.begin(9600);}void loop(){Setril.printIn(analogWrite(0));  //the middle wire is connected to port 0, which is the serial output port；delay(200);} 🔺Electric BellWhen energized, electromagnetic induction produces magnetic force, the switch (oscillator) is attracted and pulled down; When the power is cut off, the coil loses its magnetism, the switch is restored, and then energized. That is, repeat the cycle. This is also the principle of crystal oscillator.Figure  8. Electric Bell DiagramCode:void setup(){pinMode(9,OUTPUT);Setrail.begin(9600);}void loop(){Setrail.printIn(analogRead(0));analogWrite(9, map(analogRead(0), 400,700,0,255);   //map(a1,b1,a2,b2), that is, the original range of values [a1,b1] is mapped to [a2,b2];delay(200);} Ⅸ FAQ1. What is an Arduino used for?Arduino is an open-source electronics platform based on easy-to-use hardware and software. Arduino boards are able to read inputs - light on a sensor, a finger on a button, or a Twitter message - and turn it into an output - activating a motor, turning on an LED, publishing something online.2. Is Arduino illegal?The hardware designs of Arduino are open source; it is allowed to copy and further develop the designs. Note that in case a copy uses the Arduino name and/or logo on it, this board is no longer a copy but a counterfeit which is illegal to manufacture and sell.3. Can Arduino run C++?First, the Arduino compiler/IDE accepts C and C++ as-is. In fact many of the libraries are written in C++. Much of the underlying system is not object oriented, but it could be. Thus, "The arduino language" is C++ or C.4. Is Arduino easy to learn?Arduino is cost-effective and easily accessible. Arduino is easier to learn as a programming language as it is a simplified version of the C++ programming language. Arduino is cross-platform which makes it easy to run on any sort of device compared to other microcontrollers which can only run on windows.5. What is the difference between Arduino and Raspberry Pi?The main difference between them is: Arduino is microcontroller board, while Raspberry Pi is a microprocessor based mini computer (SBC). The Microcontroller on the Arduino board contains the CPU, RAM and ROM. All the additional hardware on Arduino Board is for power supply, programming and IO Connectivity.6. Why is Arduino so popular?So the Arduino hardware is easy, the Arduino IDE is simple, and the code itself is much easier to comprehend (than trying to program an off-the-shelf microcontroller). ... Another reason Arduino is so popular is because there are many people using it which means there's a lot of examples out there to work with.7. Can I sell my Arduino project?Yes, with the following conditions: Physically embedding an Arduino board inside a commercial product does not require you to disclose or open-source any information about its design. ... You may manufacture and sell the resulting product.8. Do you have to use the Arduino IDE?Can I program an Arduino board without the Arduino IDE? Yes, you can use Create web editor to program your board without the need of download the classic IDE.9. Can I use Python in Arduino?Arduino uses its own programming language, which is similar to C++. However, it's possible to use Arduino with Python or another high-level programming language. In fact, platforms like Arduino work well with Python, especially for applications that require integration with sensors and other physical devices.10. What language does Arduino code in?Arduino is programmed with a c/c++ 'dialect'. Most c/c++ will work but much of the standard libraries will not work.11. Which language is best for Arduino?Any language that has a compiler that generates Arduino compatible machine code will be perfect. As of this moment , a subset of C / C++ is the only language that is supported by the Arduino IDE.12. How do I program an Arduino?1) Use your Arduino Uno on the Arduino Web IDE.2) Use your Arduino Uno on the Arduino Desktop IDE. Install the board drivers. Open your first sketch. Select your board type and port. Upload the program. Learn more on the Desktop IDE.3) Tutorials.13. Can Arduino connect to WiFi?Connect your Arduino to the internet by adding ESP8266 WiFi Module ... Adding this module to your Arduino UNO will open you to more and exciting projects.14. Can an Arduino run Linux?Arduino have a couple of boards that support running a variant of Linux called Linino: The Arduino Yún is a microcontroller board based on the ATmega32u4 and the Atheros AR9331. The Atheros processor supports a Linux distribution based on OpenWrt named Linino OS.15. What should I learn before Arduino?Before learning Arduino you need to have knowledge of basic programming. You can choose any language like C, C++ or Java. And apart from that you need to have basic idea about electronic devices like which part it is?, How it works? etc.16. Where do I program Arduino?Arduino programs are written in the Arduino Integrated Development Environment (IDE). Arduino IDE is a special software running on your system that allows you to write sketches (synonym for program in Arduino language) for different Arduino boards.17. How many types of Arduino are there?Top 6 Different Types of ArduinoArduino UNO. The development of Arduino UNO board is considered as new compared to other Arduino boards.LilyPad ArduinoArduino MegaArduino LeonardoArduino Red BoardArduino Shields18. Is Arduino good for beginners?Arduino is easily accessible - even for those who don't know much about electronics. Arduino boards are simple a type of microcontroller. They are able to read inputs from the sensors and turn those inputs into output. Arduino is the best for beginners looking to get started with electronics for the first time.19. Which is more powerful Raspberry Pi or Arduino?Given those differences you might think a Raspberry Pi is so much more powerful and capable than Arduino, so you should use that. ... Raspberry Pi has 8. Individual I/O pins in Arduino can drive 40mA while Raspberry Pi GPIO pins can each drive a maximum of 16mA.

Ⅰ IntroductionA computer  whether it is a laptop  or a desktop has a Motherboard where a small amount of memory known as  CMOS  (complementary metal-oxide-semiconductor) stores the BIOS  settings. Hardware settings, system time, and date are the parts of BIOS  settings. BIOS  protects the data each time the computer  turns off. If  CMOS loses its power the system clock resets.CatalogⅠ IntroductionⅡ CMOS Battery Related VideoⅢ Computer BIOS Ⅳ What is a CMOS Battery ?Ⅴ What is the Lifeline of CMOS Battery?Ⅵ How do I Know My CMOS Battery Failed? Ⅶ How to Replace A CMOS Battery?7.1 Step 1: Remove the Previous CMOS Battery7.2 Step 2：What To Do After Taking Out The Battery？Ⅷ FAQ Ⅱ CMOS Battery Related VideoHow to remove cmos battery in your pc? Cmos reset / hard reset on biosCMOS Battery Video Description:In this video I will teach you how to remove your cmos battery  in your pc whether be in  ATX  or  mATX  or mini ITX motherboard  . Removing the cmos battery  for 5 minutes will give a hard reset on your motherboard  and this will clear unnecessary issues like wrong overclock, no video signal and seeing the "reboot and select proper boot drive" in your display Ⅲ Computer BIOS To comprehend the significance of a CMOS battery  , you must first comprehend what your computer  's BIOS  is.BIOS is pre-programmed into the hardware of every computer,  It is not the same as an operating system. Operating systems  can be installed, uninstalled, and updated long after the computer  has been purchased. BIOS  is something that is built into the computer  during the manufacturing process.BIOS is an abbreviation for "Basic Input/Output System." What exactly does it accomplish? Essentially, it manages your computer  's essential functions.All computer  s operate based on inputs and outputs. Assume you're launching a software application:An input is when your CPU  sends an instruction to your hard disk to retrieve the software program from storage.Your hard disk retrieves the data from the software program and sends it back to your CPU  ; this is output.The program is executed by your CPU,  It sends instructions to your graphics processor, instructing it on what image to create; an input.Your graphics processor then sends instructions to your monitor on how to arrange the pixels on the screen to create the image; this is output.Everything your computer  does can be reduced to an input or an output. The BIOS  is in charge  of managing your computer's exchange of inputs and outputs, mostly when you boot it up. BIOS  instructs your computer on how to boot up the operating system and also controls peripherals (such as the mouse and keyboard). To turn on your laptop  , you press the power button, correct? So, how is your laptop  supposed to process the power button when it is off? That is what the BIOS operated. While your computer is still waking up, it performs basic functions for it. The basic input is to press the power button. The basic output is that your operating system boots up. Next We will look at CMOS battery,  Ⅳ What is a CMOS Battery ?On your motherboard.  the motherboard  battery, also known as the CMOS (Complementary Metal-Oxide Semiconductor), functions as an RTC (Real-Time-Clock). Inside your computer.  the CMOS acts as a battery-powered semiconductor chip that stores important data. This information includes the system time, date, and system hardware settings, which are required for your computer to boot and load properly. All of this data is kept safe by a near-quarter-sized lithium battery located directly on the computer's motherboard, Figure1:CMOS battery Ⅴ What is the Lifeline of CMOS Battery?CMOS is also referred to as CMOS RAM, Non-Volatile RAM (NVRAM), or a real-time clock (RTC). The lifespan of a CMOS battery  is nearly ten years. It will differ depending on the computer's usage and environment. CMOS is used in devices such as static RAM (SRAM), microcontrollers, digital logic circuits, and microprocessors.When the computer is unable to display the correct date and time, the CMOS battery  has failed. The original button does not appear on all motherboard  s. Some of the most basic types of customization features are expansion port speed configuration, boot device order, memory handling, and power control.As we all know from personal experience, batteries do not last forever. Batteries will cease to function after a certain time. This could happen anywhere between two and ten years after the device is manufactured. If your computer is turned on, its battery will last longer than if it is turned off. Unlike other types of batteries, these are not rechargeable, and doing so may result in an explosion. Ⅵ How do I Know My CMOS Battery Failed?The following are the symptoms of CMOS battery  failure:The laptop  is having trouble booting up.The motherboard  emits a constant beeping noise.The date and time have been reset.Peripherals are not responsive or respond incorrectlyHardware drivers have vanishedYou are unable to connect to the internet.When your CMOS battery  dies, your BIOS firmware will shut down and reset to factory setting. Problems with booting up and constant beepingAs previously stated, BIOS is primarily responsible for booting up your  computer ,  Your laptop  may have a difficult time booting up without the battery, or it may not boot up at all. You may also hear a constant beeping noise from the motherboard.  which is another sign of a battery failure.Date and time from a long, long time agoIf your laptop  boots, you may notice that the date and time have been reset. They've most likely reset to a date in the distant past. Even when your computer is turned off, BIOS keeps a real-time clock that keeps track of the date and time. That procedure is maintained by CMOS (which is sometimes referred to as a real-time clock in and of itself). If the date and time have mysteriously reset, it's a good indication that the CMOS battery  has died.Keyboard performance is erratic.It's possible that your peripherals aren't responding; for example, you can't move your cursor or click on any icons, and the laptop  isn't reading any of your keyboard inputs.Alternatively, your peripherals may be thrown out of whack; your cursor may be inaccurate, and your key inputs may result in strange responses from the operating system.Alternatively, your customized keyboard configuration has been reset to the default. Because BIOS is in charge  of managing peripherals at startup, these are all indications of CMOS failure.Drivers vanishIf you've installed any drivers on your computer.  such as those for your home printer, a CMOS failure may cause those drivers to vanish (you'll need to download and reinstall them).There is no internet connection.You may also be unable to connect to the internet if your battery dies. BIOS is in charge  of keeping hardware and network drivers up to date.One thing you should be relieved about is that CMOS failure usually does not result in the loss of any personal files. Nothing in storage has been harmed. Once you've replaced the battery, you'll still have access to all of your photos, videos, and documents. Failure of ttery  Ⅶ How to Replace A CMOS Battery?Ground yourself before you touch your patient. That means making sure that any static electricity (which can be generated in small charge  s between your body and clothing but is weak enough not to hurt you) does not pass through the delicate computer parts, which may seem insignificant but can seriously damage some of the more delicate components inside your case.Important points include placing your computer case on a non-conductive (non-metallic) table or surface before opening it for treatment and standing on bare feet in contact with the floor. 7.1 Step 1: Remove the Previous CMOS BatteryTo do so, open your computer's case and locate the CMOS battery on the  motherboard ,  If you're treating a laptop.  you'll need to open the laptop  's back panel. Because it resembles a large silver coin sitting on your motherboard  , the CMOS battery is easy to locate. Figure2:motherboard The battery in most systems and laptops is held in place by a small clip next to it. Simply slide the battery out from under the clip like a big round SIM card, and you'll have the troublesome little silver coin in your hand.Also, under no circumstances should the clip be bent.As a result, it will be unable to hold the new battery in place. You're treating your computer.  and as the saying goes, "first not harm."Figure3:new battery And there is one more thing;In some laptops, the CMOS battery may be covered with non-conductive protection and attached to two wires that are connected to the laptop's motherboard  via a connector similar to this:Figure4: laptop's motherboardAnd, you know, it's also possible that you can't find the CMOS battery on your laptop's back panel;Because some manufacturers do not allow battery replacements, and if you are still insistent on removing the battery;In any case, you can look online for a 'how to disassemble your laptop' tutorial video.Like on the YouTube;And this will help you understand how to disassemble your laptop because the CMOS battery may be attached to the other side of your laptop's motherboard, Here's a picture of the laptop without a CMOS battery in the back panel:Figure5: back panel So, whatever battery type your computer is using, simply disconnect or remove it.Even if the CMOS Battery is soldered to the motherboard  in the following manner:Figure6:Battery is soldered 7.2 Step 2：What To Do After Taking Out The Battery？You have to now purchase the same CMOS battery for your laptop or computer that you recently removed from your laptop or computer, So, you'll need to go to a computer store or order the battery online. Whatever you do, make certain that you purchase the same type of battery. Ⅷ FAQ1. How do I get the CMOS out of the motherboard without damaging it?Use a flat head screwdriver, push the metal tab back away from the battery.  It should not take much force, and the battery will just pop out.2. Is the CMOS battery the same battery found in Automotive Key Fobs?Excellent question, YES!  The CR2032 can be found in many devices from calculators, wrist watches, medical devices, toys, and many more.3. Can a motherboard run without a battery?Technically, YES.  Removing the CMOS battery will allow your computer to run however, you will lose the date and time settings, the computer will boot with default BIOS settings or you will have to choose the drive that the OS is installed every time you start your computer.4. Will removing the motherboard battery reset BIOS?This is an excellent question I get asked alot.  The short answer is YES.  If you remove the battery, wait approximately 5 minutes and then reconnect the battery.5. Can a CMOS battery cause a black screen?A faulty battery removes all of your boot settings.  It is very possible to see nothing but a black screen when booting up a computer with a dead CMOS.  For example if you have a secondary video adapter that your monitor is plugged into and your BIOS has reset to default settings, your onboard video would be the new display and not your primary video adapter.

IntroductionNow face masks are necessary elements during the COVID. In practice, they are intended for one-time use, and to a large extent, it is environment unfriendly. Also during a shortage, repeated use is inevitable and it is necessary to have a disinfection mechanism. During the ongoing SARS-CoV-2 pandemic, hospitals, medical centers, and research institutions implemented different disinfection methods for these masks, usually involving ultraviolet germicidal exposure (UVGI) or some kind of heating methods. Nevertheless, these methods are not suitable for many ordinary people. What’s more, due to shortages, the reuse of these masks has become the only option. There is evidence that SARS-CoV-2 still exists on the surface of surgical masks even after 7 days, so the demand for feasible mask disinfection methods has further increased. Here will introduce a special device to do that.Introduction: Understanding the CoronavirusCatalogIntroductionⅠ Disinfection Device Production InstructionsⅡ Device Design Processes2.1 Device Size2.2 Thermal Test2.3 Box Lid Design2.4 UV-C System2.5 Making the Mask PlacementⅢ Set Up Arduino and Sensor3.1 Arduino Overview3.2 Material3.3 Sensors Installation3.4 Arduino Control3.5 AlarmⅣ Using GuideⅤ Temperature Cycle5.1 Heat Inactivation of Viruses5.2 Security ConsiderationsⅥ ConclusionⅠ Disinfection Device Production InstructionsThe device aims to create a low-cost portable device that can effectively use UVGI and dry heat to disinfect masks carry SARS-CoV virions, and can be easily operated by those who need it.Device Setup DiagramFigure 1. Device Setup Diagram1) The temperature must be kept within 65±5℃.2) The lamp must provide UV-C wavelength. UVC bulbs that emit very short ultraviolet wavelengths from 100 to 280 nanometers that damages the DNA of bacteria, viruses, and other pathogens. You should be careful, ultraviolet C is the most dangerous type of ultraviolet light in terms of its potential to harm life on earth.3) The duration of the disinfection cycle is at least 30 minutes. Because coronavirus is more sensitive to heat. A temperature of 56 degrees can kill the coronavirus within 30 minutes. So no more than 30 minutes to avoid potential mask degradation and function losses.Figure 2. Device Operational DisplayFigure 3. Device Physical ViewⅡ Device Design Processes2.1 Device SizeFigure 4. Device Size2.2 Thermal TestFigure 5. Thermal Test DiagramFigure 6. Test with ThermometerFigure 7. Test Boite Temperature Manufacturing of heating system:1) A frying pan with a diameter of 22cm (induction compatible) without handle.2) Cover the frying pan with aluminum foil to reflect UV-C light.3) Make a 20cm hole in the center of the bottom surface of the box.4) In order to maintain the position of the frying pan, please use four metal brackets as shown in the figure.Figure 8. Frying PanNote: The frying pan should not close to the wood of the box because it will reduce the thermal efficiency. Therefore, you must select the appropriate hole diameter and shape the metal bracket according to the following figure:Figure 9. Frying Pan Installation Diagram 2.3 Box Lid DesignFigure 10. Box Lid Design2.4 UV-C SystemFigure 11. UV-C LampFor the UV-C source in this device, it is an 11W bulb from household aquarium. As shown in the picture, the UV-C bulb is taken out and installed on the top cove. The installation method of the bulb is to make 4 holes in the top cover, and use the cable tie/cable tie and soft cushion to fix the bulb firmly. And the top surface is covered with aluminum to reflect ultraviolet radiation.You can feel free to use UV-C lamps from other sources. However, if you cannot access the crystal tube (used in this project), please do not use glass as a substitute, because glass will block ultraviolet radiation.2.5 Making the Mask PlacementThe mask will be placed on top of the metal frame. The I wire frame is made of thin copper wires, and each wire has 30mm spacing apart. The wire stand is located 120mm above the bottom surface. Next secure the wire racks together by passing the wires through the small holes on the front and back surfaces of the box.Figure 12. Mask PlacementⅢ Set Up Arduino and Sensor3.1 Arduino OverviewFigure 13. Arduino Overview3.2 MaterialArduino UNO Rev3Grove Basic Shield V2, 0Infrared temperature sensorLight SensorPush ButtonPiezo SpeakersFour-digit LED DisplayAdapter power supply DC 12V3.3 Sensors InstallationFigure 14. Sensor Introduction3.4 Arduino ControlINIT: In this state, the LED display indicates the temperature, but you have to wait for it to reach the threshold (70℃) before starting cycle counting in the COUNT state.Count: The number of minutes from 30 to 0 is displayed on the LED display next to the temperature digits. Additionally, in the case of too low temperature, or if the UV lamp is turned off, the status will change to ERR.END: This is the normal state at the end of the elapsed time. The speaker will remind. Press the button to enter INIT again.ERR: This is an error state, if the temperature is too low or the UV lamp is turned off, it will run. In terms of it, repeat the last step above.Code Download: LED Backpack Libraries and Arduino Wiring.3.5 AlarmIn fact, there are few alarm conditions. If the alarm is on, there will be a specific sequence on the speaker and a message will be displayed on the screen.Alarm condition: If the system is in ERR state (mentioned above) or the temperature is too high (over 75℃).Figure 15. Alarm System Diagram Ⅳ Using Guide1) Put the box on top of the induction (or resistance) stove.2) Turn on the power of Arduino.3) Close the box and start heating at 70~80% of the power of the induction cooker.4) Wait until the temperature reaches 60℃, and then reduce the variable power of the induction cooker to 30%.5) Now you can open the device, put the mask in and close it.7) Press the button to start, the remaining time (30 minutes) should be displayed.8) From now on, you need to wait 30 minutes, and there will be a signal on the speaker.9) If you want to restart a new cycle from the initial state, just press the button.Note: When the timer is counting the elapsed time, the dots between the Timer and Temperature displays will flash at 1 second intervals. Ⅴ Temperature CycleFigure 16. First Heat CycleFigure 17. Cycle with Opening-Closing 5.1 Heat Inactivation of VirusesSince the time of Pasteur, people have known the ability to remove microorganisms through moist heat, usually below 100℃. In this device, we implemented dry heat, which is reported to be effective in eliminating the infectivity of SARS-CoV. The analysis showed that the virus is largely inactivated within 30-90 minutes at 56℃, almost completely inactivated at 65℃ in 20-60 minutes, and at 75℃ in 30-45 minutes. In addition, a recent study showed that SARS-CoV-2 will lose all its infectivity at 56℃ after 30 minutes or at 70℃ after 5 minutes.According to these evidences and additional considerations regarding the effects of these disinfection methods on the function of the mask, we decided to set the heat exposure of the protocol used with the equipment to 65℃/30 minutes.5.2 Security Considerations• UVC radiation is harmful to human skin and eyes, so the UVC bulb should only be turned on when the box is completely closed.• Be careful with the metal parts of the box, they may be very hot after heating and may burn your skin when you touch them directly. Ⅵ ConclusionTaking into account the collected evidence and the technical details of the equipment, we decided to set the disinfection protocol to UVC irradiation for 30 minutes and 65±5℃ dry heat. In addition, the time required for the device should reach the required temperature and light intensity, which must be calculated. Using these specifications of UVC or heating alone should be sufficient to eliminate almost all SARS-CoV-2 infectivity, and the simultaneous action of the two should increase the effectiveness to reach a safer level.According to the available scientific evidence, the disinfection program may eliminate almost all SARS-CoV infectivity and will certainly make the masks safer to reuse than without any disinfection. However, it is designed in good faith and to the best of professional knowledge and ability, but the following must be stated:The use of this equipment to inactivate SARS-CoV-2 has not yet undergone proper laboratory testing, and it is impossible to confidently confirm the actual impact on the filtering capacity of the mask in advance.

ⅠIntroduction RTC is an abbreviation for Real-Time Clock. RTC modules are simply TIME and DATE remembering systems with a battery setup that keeps the module running in the absence of external power. This keeps the TIME and DATE current. As a result, we can get accurate TIME and DATE from the RTC module whenever we want. Catalog ⅠIntroduction Ⅱ RTC Module Explaintion 1.1 What is RTC module？ 1.2 Timing Ⅲ DS1302 RTC Module Basics 3.1 DS1302 RTC Module Pinout 3.2 DS1302 Pin Configuration 3.3 Features 3.4 Technical Specifications  3.5 Block Diagram of DS1302 RTC Chip Ⅳ DS1302 RTC Module with Arduino 4.1 Setting up the Hardware 4.2 Making the Code Ⅴ FAQ   Ⅱ RTC Module Explaintion 1.1 What is RTC module？ A real-time clock (RTC) is an electronic device that measures the passage of time (typically in the form of an integrated circuit). Although the term is most commonly associated with devices found in personal computers, servers, and embedded systems, RTCs can be found in almost any electronic device that requires an accurate time of day. A real-time clock mechanism and a long-lasting battery are used by an RTC module to keep track of the time. On a small board with five pins, the module contains a 3V lithium-ion battery, a 32 kHz crystal, and a DS1302 chip. The DS1302 chip is extremely power efficient and can run for up to 5 years on a 3V lithium battery. Figure1:RTC Module     The power supply voltage  is 5 volts. The serial  I2C  communication protocol is used by the RTC module.  which makes interfacing with the microcontroller very simple. Aside from VCC and GND, only two pins (CLK and DAT) are required for interfacing with  Arduino . CLK and DAT are the required SCL and SDA pins for  I2C communication, respectively, while RST is the reset pin (optional).   1.2 Timing The majority of RTCs use a crystal oscillator,[8][9] but some can use the power line frequency.  The crystal frequency is typically 32.768 kHz, which is also the frequency used in quartz clocks and watches. It is a convenient rate to use with simple binary counter circuits because it is exactly 215 cycles per second. The low frequency saves power while remaining above the range of human hearing. The temperature has little effect on the size of these crystals' quartz tuning forks, so the temperature has little effect on their frequency. Some RTCs employ a micromechanical resonator on the RTC's silicon chip. This reduces the size and cost of an RTC by reducing the number of parts. Micromechanical resonators are much more temperature-sensitive than quartz resonators. So, using an electronic thermometer and electronic logic, compensate for temperature changes. Typical crystal RTC accuracy specifications range from 100 to 20 parts per million (8.6 to 1.7 seconds per day), but temperature-compensated RTC ICs are available with accuracy as low as 5 parts per million. In practice, this is adequate for celestial navigation, the traditional function of a chronometer. Chip-scale atomic clocks became available in 2011. Despite being significantly more expensive and power-hungry (120 mW vs. 1 W), they keep time to within 50 parts per trillion.   Ⅱ RTC Module Related Video: What is RTC and how it is working || real time clock|| diyproject || graspelectronics RTC Module Video Description: what is rtc ? and how it is working ? RTC stands for real tme clock. RTC module code  is ds3231 the code is given in the datasheet for all components  . it is work in 3.3v  5v may kill the module. it is used to maintain accurate time keeping when main power to the device is interrupted. The rtc maintan maintains second,hours, day,date, month and year information. Real time clockThe date at end of the month is automatically adjusted for month with fewer then 31 days including corrections for leap years.   Ⅲ DS1302 RTC Module Basics Before we start this project, we will have a look at basics of DS1302 RTC Module. 3.1 DS1302 RTC Module Pinout Figure2: Pinout   3.2 DS1302 Pin Configuration Pin No. Pin Name Description 1 Vcc2 Second supply input, when Vcc2 is greater than Vcc1 + 0.2V, DS1302 powers through this pin 2,3 X1 and X2 For connecting external crystal oscillator of 32.768kHz 4 GND Ground 5 CE This pin set to HIGH during a Read or a Write 6 I/O (Data Line) This is the bi-directional data pin to 3-wire interface 7 SCLK(Serial Clock) Used to synchronize data movement on the serial interface 8 Vcc1 Rechargeable energy source connected to this pin   3.3 Features Minutes, seconds, date, hours, month, day of the week, year, and leap-year compensation up to 2100 are all counted in real-time.Single and multiple (Burst mode) data transfers for Clock or RAM data read and write31*8 general-purpose battery-powered RAMSimple interface based on three TTL-compatible wiresFull operation from 2V to 5.5VSmall sizepin DIP and 8-pin SO packages are available. 3.4 Technical Specifications 3.3V is the typical supply voltage.Voltage range (concerning ground) on any pin: -0.5V to 7.0°CTemperature range (commercial): 0°C to +70°CTemperature range (Industrial): -40°C to +85°CTemperature range for storage: -55°C to +125°CTemperature for Soldering: 260°C Note: The DS1302 Datasheet, which is linked at the bottom of this page, contains all of the technical information.  3.5 Block Diagram of DS1302 RTC Chip Figure3:Diagram   3.6 How to Use a DS1302 Chip？ A typical DS1302 operating circuit is shown below. The DS1302 has two power inputs, one from the cell and one from the controller. To generate the required frequency, a crystal oscillator with a frequency of 32.768 kHz is used. The data line, reset pin, and serial-clock pins of the DS1302 are connected to the microcontroller for interfacing. Figure4:Example   Ⅳ DS1302 RTC Module with Arduino 4.1 Setting up the Hardware Pins A4 and  A5  on the  Arduino are dedicated to I2C communication. However, with the assistance of software code, any pin can be used to serve the purpose. This is known as a software I2C bus. For our purpose, we will use the "Rtc by Makuna" library, which can be found in the Arduino IDE's Tools -> Manage Libraries... menu. Following installation, the examples provided with the library can be used to learn more about the functions and initialization methods. Figure5:Library Manager Arduino  To use the following code, connect the RTC module's DAT, CLK, and RST pins to Arduino's digital pins 6, 7, and 8. 4.2 Making the Code Now we must write the C code to set the current date and time in the RTC module, read from the module, and write to the serial monitor every second.   Figure6 :Code for connection with RTC Module The line ThreeWire DatClkRst (6,7,8); creates a bundle of three wires that will be used to initialize the object Rtc from the RtcDS1302 class using the command RtcDS1302ThreeWire> Rtc(DatClkRst); The function SetDateTime resets the DS1302 chip's date and time. The date and time at the time of Arduino's C code compilation are saved in the RtcDateTime object "compiled." The loop() method has a one-second delay. Date and time are read from the RTC module and displayed on the serial monitor in each iteration. To learn how to use this RTC module, remove the line and flash the Arduino with the updated code again. Even if the Arduino's power is turned off or the RTC module is disconnected and reattached, the Arduino will be able to read and display the correct real-time.   Ⅴ FAQ 1. Which RTC module is best? Choosing The Right RTC For Your Project The DS-1307 is often the default choice for an RTC. ...The DS3234 has the distinction of using an SPI interface instead of I2C. ...The RV-1805 draws so little power that this Sparkfun module gets by without a backup battery at all. 2. What is RTC module DS3231? The DS3231 is a low-cost, extremely accurate I2C real-time clock (RTC) with an integrated temperature- compensated crystal oscillator (TCXO) and crystal. The device incorporates a battery input, and maintains accurate timekeeping when main power to the device is interrupted. 3. What is RTC in mobile phone? A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the passage of time. 4. What is RTC in laptop? The real-time clock, or RTC, maintains the internal clock … in real time. That is how the laptop knows the time as well as the date whenever you turn it on. ... Or you can keep the laptop plugged into an AC source. 5. Does RTC work without battery? The RTC module accurately keeps time with a precise oscillator and is maintained with a small battery (not included). 6. How does RTC module work? An RTC maintains its clock by counting the cycles of an oscillator – usually an external 32.768kHz crystal oscillator circuit, an internal capacitor based oscillator, or even an embedded quartz crystal. Some can detect transitions and count the periodicity of an input that may be connected. 7. What is the difference between DS1307 and DS3231? The main difference between the DS3231 and DS1370 is the accuracy of time-keeping. DS1307 comes with an external 32kHz crystal for time-keeping whose oscillation frequency is easily affected by external temperature. This usually results with the clock being off by around five or so minutes per month.