How to Use Semaphore and Mutex in FreeRTOS with Arduino

In previous tutorials, we have covered the basics of FreeRTOS with Arduino and the Queue kernel object in FreeRTOS Arduino. Now, in this third FreeRTOS tutorial, we will learn more about FreeRTOS and its advance APIs, which can make you understand the multi-tasking platform more deeply.

Semaphore and Mutex (Mutual Exclusion) are the kernel objects that are used for synchronization, resource management and protecting resources from corruption. In the first half of this tutorial, we will see the idea behind Semaphore, how and where to use it. In the second half, we will continue with Mutex. Read the complete tutorial

Stereo Audio Pre-Amplifier Circuit with Bass and Treble Control using Transistors

The use of an audio pre-amplifier ensures good audio quality and provides options to modify our sound system by using this as a primary audio circuit/device before feeding the audio signal to your amplifier/subwoofer/home theatre system. Also, we can control bass and treble for different songs and get a wide range of control over our audio system. This type of circuit that provides Bass and Treble control is also known as a BT Circuit Board. In this article, we will build a stereo pre-amplifier circuit with bass and treble control.

View the full circuit design article: https://circuitdigest.com/electronic-circuits/stereo-audio-pre-amplifier-circuit-with-bass-and-treble-control

For more circuits, visit: Electronics Circuits

DIY Automatic Hand Sanitizer Dispenser

In this project, we will build an Auto Hand Sanitizer Dispenser with an LCD which also shows the live count of Coronavirus cases. This project will use ESP32, Ultrasonic Sensor, 16x2 LCD Module, Water pump, and Hand Sanitizer. We are using Esri’s API Explorer to get the live data of Covid19 infected people. An ultrasonic sensor is used to check the presence of hands below the outlet of the sanitizer machine. It will continuously calculate the distance between the sanitizer outlet and itself and tells the ESP to turn on the pump whenever the distance is less than 15cm to push the sanitizer out.

Watch the video below for the working of this automatic hand sanitizer dispenser.




For the full project tutorial, visit: CircuitDigest.com

Best Innovative Arduino Projects

See below links for the complete project tutorials:

1. Metal Detector using Arduino

2. Arduino based Fire Fighting Robot

3. Arduino based Self Balancing Robot

4. Gesture Controlled Robot

5. Arduino Color Sorting Machine

6. Arduino based Whistle Detector 

7. Arduino based Automatic Water Dispenser

8. Arduino based Pet Feeder 

9. Arduino Musical Water Fountain 

10. Arduino based Record and Play Robotic Arm 

11. Arduino based Snake Game 

12. Arduino based CNC Plotting Machine 

13. Arduino based IR Thermometer 

14. Arduino based Smart Watch 

ESP32 Camera Module for Video Streaming and Face Recognition

In this project a Face Recognition System is build using ESP32-CAM which can also be used as an ESP32-CAM Security system by recognizing the face of unauthorized persons. ESP32-CAM is a very small camera module with the ESP32-S chip which makes it easier to build a face recognition system without using any complex programming and any extra components.



Watch the video below for a full demonstration of this ESP32-CAM security system:



View the full project article on Circuit Digest

How to Build a Smart Plug using ESP8266 to Control Your Home Appliances ...

In this project I will show you how you can build your very own Smart plug using ESP8266 Wi-Fi module. The device that we built can easily be plugged into any exiting AC socket and then on the other end you can connect the actual load simply by plugging it into this socket on our device. After that just keep the main switch of your socket always on, and you can control your Load directly from your Smartphone.

Check out the full DIY tutorial here with necessary circuit diagrams and codes: https://circuitdigest.com/microcontroller-projects/diy-smart-plug-using-esp8266

Control NEMA 17 Stepper Motor with Arduino and DRV8825 Stepper Motor Dri...

To learn more about NEMA 17 stepper motors and how to control it using Arduino and DRV8825 stepper motor driver, visit this tutorial: https://circuitdigest.com/microcontroller-projects/control-nema-17-stepper-motor-with-arduino-using-drv8825-stepper-motor-driver