[Open Source] Ultra-low Cost Seamless Car Entry Solution

Keyless entry project design documents 20240923.rar

PDF_【Open Source】Ultra-Low Cost Seamless Car Entry Solution.zip

Altium [Open Source] Ultra-low Cost Seamless Car Entry Solution.zip

PADS - [Open Source] Ultra-Low Cost Seamless Car Entry Solution.zip

BOM_【Open Source】Ultra-Low Cost Seamless Car Entry Solution.xlsx

92038

NE555 Electronic Keyboard

The NE555 chip is a classic integrated circuit commonly used in applications such as timers, pulse generators, and oscillators. Its versatility makes it very popular among electronics enthusiasts and engineers. This project is a simple electronic keyboard built using the NE555 chip.

The NE555 chip is a classic integrated circuit commonly used in applications such as timers, pulse generators, and oscillators. Its versatility makes it popular among electronics enthusiasts and engineers. Below is a brief introduction to building a simple electronic keyboard using the NE555 chip.
NE555 Chip Introduction :
The NE555 chip is a timer IC introduced by Signetics (now NXP) in 1972. It features highly stable time delay capabilities and can be used as a pulse generator or oscillator. Its basic functions include monostable and bistable modes, and the output frequency and pulse width can be adjusted as needed.
Basic Principles of Building a Simple Electronic Keyboard :
The simple electronic keyboard, based on the NE555 chip, can generate sound signals of different frequencies using its oscillator mode, thus simulating different pitches. By adjusting the resistance and capacitance values ​​of the NE555 chip, different frequency pitches can be achieved.
Materials List:

NE555 chip x1,
Resistors (various resistance values)
, Capacitors (various capacitance values)
, Buzzer or Speaker,
Key

Circuit Design,


NE555 Chip Configuration

: Configure the NE555 chip to oscillator mode (also known as square wave generator mode).
Connect the power supply to pin 8 (VCC) and pin 1 (GND) of the NE555 chip.



To set the oscillation frequency,

connect a capacitor (C1) between pins 6 and 2 of the NE555; this determines the oscillation frequency.
The pitch can be adjusted by changing the resistors (R1) between pin 7 (discharge pin) and pin 6, and (R2) between pin 6 and pin 2. A potentiometer can be used instead of a fixed resistor for pitch adjustment.



To output sound

, connect pin 3 (output pin) of the NE555 chip to the positive terminal of a buzzer or speaker.
Connect the negative terminal of the buzzer or speaker to ground (GND).



Experimental Procedure:

Connect the components of the NE555 chip according to the circuit diagram.
Adjust the resistance values ​​using the buttons and observe the changes in the sound emitted by the buzzer to achieve different pitches.
Multiple such circuits can be designed, and different circuits can be switched using buttons to simulate a simple electronic keyboard.

Debugging and Improvement

: Adjusting the pitch: Different pitches can be obtained by adjusting different resistor values.
Sound Effects: Experiment with adding filters or modulation circuits to the buzzer or speaker to achieve richer sound effects.
Expanded Functionality: Add more buttons, each connected to a different NE555 circuit, to achieve multi-tone keyboard effects.

Summary:
Building a simple electronic keyboard using the NE555 chip is a fun and educational project. By adjusting resistors and capacitors, you can create various pitches and experience the joy of electronic music. This project also provides a good practical opportunity to learn and master basic electronic circuit design.

PDF_NE555 Electronic Keyboard.zip

Altium_NE555 electronic keyboard.zip

PADS_NE555 Electronic Keyboard.zip

BOM_NE555 Electronic Keyboard.xlsx

92039

The Magic Wand v0.8

This is a circuit design for making magic wand toys. It can also be used as a development board with a wide range of integrated peripheral functions.

Magic Wand Project Functions:

Wand Mode: Users wave the wand to perform specific actions and recite spells (optional). The wand then controls home appliances via infrared remote control, simultaneously playing sound and light effects. The LCD displays the recognized graphic shape and related prompts.
Prophet Mode: Users press a button, speak their desired topic, and release the button. The wand connects to a large language model, acquires its output, converts it into speech, and plays the speech to the user. The LCD displays the prophet's image.
BLE Air Mouse: Simulates a BLE mouse device to control a TV or computer. The middle button is used for single or double clicks, and the up, down, left, and right buttons are used for auxiliary directional control.
Night Light: Automatically turns on LED lights when the illuminance is below a certain threshold and there is activity. The MCU operates in ULP ultra-low power mode throughout the process.
Automatic Lighting: Automatically turns on home lights via infrared remote control when the illuminance is below a certain threshold and there is activity (lights must support infrared remote control).
Wand: Waving the wand displays the selected graphic or text on an LED strip. Graphic or text styles can be automatically obtained by the MCU from the network (and the resolution is automatically reduced to suit the density of the LED strip).
Intercom mode: Two wands can communicate via voice over a 2.4G Mesh network.
Configuration mode: Connect to the MCU's Wi-Fi access point, open the specified address in a browser, and configure the specific parameters of the above functions through the web interface.
Voice control: Most of the above functions support voice control. The LCD will prompt the user with voice commands as needed.

 
Hardware Function Verification Status:




Main

Electronic Modules
Verification Completed
More Description:


Motion Perception
MPU6050
Yes
 


Voice Playback
ES8311, AW8010B
Yes Can
play MP3 files stored in Flash or MP3 data streams downloaded from the network


Voice Input
ES8311, ZTS6117 Yes
Used
for voice command recognition


Infrared Control
IR940F3

No (This circuit was verified using other models in the previous version)

Used to control the switching of home appliances


Infrared Receiver
DY-IRMHA384-T05-2KB

No
(This circuit was verified using other models in the previous version)

Used to learn infrared remote control commands for home appliances


LED Light
F8MM The 0.75W light source
is
used as a flashlight or night light.


The WS2812B LED strip
 
is
used to display light and shadow effects . The PT550F3


ambient light sensor is used to prevent daytime illumination in night light mode. The GMT128-01 (round screen) LCD display is used to display system status, animated characters, text, etc. The MG58F18 human presence sensor is used to automatically wake the wand when it is near, and to automatically turn on the light in night light mode. The five-way button has the middle button connected to GPIO0; it can be used as a BOOT button during startup, and its function is defined according to the wand mode during normal operation. The up, down, left, and right buttons use an ADC for input detection, and their functions are defined according to the wand's operating mode. The BLE air mouse ESP32S3R8 is a prophetic mode ESP32S3R8. The W25Q256JVEIQ is used for chatting with large language models. Battery voltage detection is used to report battery voltage. This version has an issue: the installation orientation of the human presence sensing radar module does not conform to the housing design requirements. External pull-up or pull-down resistors are not designed for the GPIO used to wake the MCU from deep sleep (to further reduce current during deep sleep).


















 







 









 





 

PDF_The Magic Wand v0.8.zip

Altium_Magic Wand v0.8.zip

PADS_Magic Wand v0.8.zip

BOM_The Magic Wand v0.8.xlsx

92041

Human body sensing environmental detection exhaust fan

I built my own exhaust fan for the dormitory toilet. The system includes: a lithium battery, a control board and expansion board, and a PWM fan. It has the following functions: PWM fan speed measurement, PWM fan speed control, lithium battery voltage detection, temperature and humidity detection, ammonia concentration detection, and OLED information display.

I built my own exhaust fan for a dormitory toilet. Its main function is to detect the toilet environment and whether anyone is in the room, thereby controlling the fan speed to achieve fully automatic intelligent ventilation. The
system consists of

an Arduino UNO R4 control board,
a self-made expansion board
, a lithium battery,
a PWM fan, and is shown in the physical demonstration.