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Karaoke Machine
| Name | Giurgiu Andrei-Ștefan |
|---|---|
| Group | 335CA |
Introduction
The project consists of creating a karaoke mechanism, using a speaker for the instrumental and an LCD screen for the lyrics. The user can choose from a preset selection of songs, loaded on a microSD card. The songs which are listed at the beginning on the screen, can be selected using buttons. The speaker volume can also be adjusted using a potentiometer.
The goal of the project is to create a relaxing and fun atmosphere for the users.
General description
The ESP32 is the main component of the project, since it will be in charge of reading data from the card and send the audio signal to an amplifier using the I2S protocol.
The MAX88357A amplifier will take the digital signal from the ESP32 and transform it into a strong analogue signal. After this the sound will be sent to the speaker.
The main storage component is a 16GB microSD card, formatted as Fat32. The instrumental files are stored in the .mp3 format and the lyrics files in the .lrc format, which is a text format with timestamps before the text, so that syncing with the instrumental is easier.
The user interface is made of three classes of components: the 20×4 LCD display with an I2C interface, the volume adapter and the buttons. The display is a simple LCD with an I2C module attached, which at the beginning will show the available songs on the device. Using the buttons, the user can select a song and play it.
Block Scheme
Hardware Design
The list of components used is:
- ESP32-WROOM-32D Microcontroller
- MAX98357A Amplifier
- MB102 Power Module
- LCD Display with PCF8574 I2C module
- microSDHC Card
- 40mm 3W Speaker
- MicroSDHC Reader Module
- Potentiometer
- Buttons
- 2x Breadboard
Component Pinout
| Component | Pin Name | Connected To |
|---|---|---|
| ESP32-DEVKITC-32D | 3V3 | Potentiometer (Top Pin) |
| IO34 | Potentiometer (Wiper) | |
| IO27 | PLAY/PAUSE BUTTON | |
| IO14 | UP BUTTON | |
| IO13 | DOWN BUTTON | |
| GND | Common GND | |
| 5V | MB102 (VCC2) | |
| IO23 | Micro SDHC reader (MOSI) | |
| IO22 | PCF8574 (SCL) | |
| IO21 | PCF8574 (SDA) | |
| IO19 | Micro SDHC reader (MISO) | |
| IO18 | Micro SDHC reader (SCK) | |
| IO5 | Micro SDHC reader (CS) | |
| IO16 | MAX98357A (DIN) | |
| IO26 | MAX98357A (BCLK) | |
| IO25 | MAX98357A (LRC) | |
| MB102 Power Supply | VCC2 | ESP32 (5V), MAX98357A (Vin), PCF8574 (VCC), Micro SDHC reader (VCC) |
| GND | Common GND | |
| VCC1 | Not Connected | |
| MAX98357A | LRC | ESP32 (IO25) |
| BCLK | ESP32 (IO26) | |
| DIN | ESP32 (IO16) | |
| GAIN | Not connected | |
| SD | Not Connected | |
| GND | Common GND | |
| Vin | MB102 (VCC2) | |
| + | Speaker (+) | |
| - | Speaker (-) | |
| PCF8574 | VCC | MB102 (VCC2) |
| GND | Common GND | |
| SDA | ESP32 (IO21) | |
| SCL | ESP32 (IO22) | |
| Micro SDHC reader | CS | ESP32 (IO5) |
| SCK | ESP32 (IO18) | |
| MOSI | ESP32 (IO23) | |
| MISO | ESP32 (IO19) | |
| VCC | MB102 (5V) | |
| GND | Common GND | |
| Potentiometer | Top Pin | ESP32 (3V3) |
| Wiper | ESP32 (IO34) | |
| Bottom Pin | Common GND | |
| PLAY/PAUSE BUTTON | Pin 1 | ESP32 (IO27) |
| Pin 2 | Common GND | |
| UP BUTTON | Pin 1 | ESP32 (IO14) |
| Pin 2 | Common GND | |
| DOWN BUTTON | Pin 1 | ESP32 (IO13) |
| Pin 2 | Common GND | |
| Speaker | + | MAX98357A (+) |
| - | MAX98357A (-) |
Electrical Scheme
Software Design
Under construction while I think about using State Machine or FreeRTOS.
Results
To be determined after Software Milestone.
Concluzii
To be determined after Software Milestone.
Download
Click here.
Journal
- 15.04.2026: First discussion with the assistant regarding the project theme.
- 05.05.2026: Partial creation of the technical documentation, which contains the project theme, block diagram and list of components.
- 08.05.2026: Add the electrical scheme of the project.
- 09.05.2026: Add the component pinout and refined the general description section.
Resources
Datasheets
| Component | Link Datasheet |
|---|---|
| ESP32-WROOM-32D | Datasheet microcontroller |
| Amplifier MAX98357A | Datasheet MAX98357A |
| LCD 20×4 | Datasheet display |
| MB102 Power supply module | Datasheet MB102 |
| MicroSDHC reader module | Datasheet MicroSDHC |
