Introduction

We know that the chip commonly used in the Arduino development board is the AVR microcontroller series produced by Atmel. The most common is the ATmega328P, widely used on the Arduino Uno development board. Other commonly used AVR chips include the ATmega2560 and ATmega32U4. It is very convenient to use the Arduino platform to develop AVR microcontrollers. The Arduino IDE provides a clean, easy-to-use development environment that simplifies writing and uploading code. It provides a set of simplified function libraries and API so that developers can easily interact with the hardware of ATmega328P without a deep understanding of the underlying register operations.

Catalog

Ⅰ What is ATmega328 ?

The Atmega328P is an 8-bit microcontroller chip that can be used in various control systems due to its strong performance and low power consumption. Because it can be found in Arduino boards, it is the most widely used AVR controller. The ATmega328P is capable of supporting analog input/output pins and serial communication interfaces. It employs 2KB of SRAM memory and 32KB of programmable flash memory. The Atmega328P is a popular microcontroller with many uses, particularly in embedded systems, automation, and electrical equipment control.

Ⅱ ATMega328 Pinout

ATMega328 Pinout 28 PDIP 

Figure1-ATMega328 Pinout 28 PDIP 

Figure2-28MLF Top View

Figure3- 32MLF and 32TQFP

Ⅲ ATMega328 Pinout Configuration

Ⅳ ATmega328 Features

• CPU: The ATmega328 features a high-performance 8-bit AVR RISC-based CPU with a clock speed of up to 20 MHz. It executes most instructions in a single clock cycle, providing efficient and fast processing.
• Memory: It has 32KB of in-system programmable Flash memory for storing the program code, 2KB of SRAM for data storage, and 1KB of EEPROM for non-volatile data storage.
• I/O Pins: The microcontroller has a total of 23 general-purpose I/O (GPIO) pins, including 14 digital input/output pins and 6 analog input pins. These pins can be configured for various purposes, such as reading sensors, driving output devices, and communication.
• Communication Interfaces: ATmega328 supports multiple communication interfaces, including UART (Universal Asynchronous Receiver-Transmitter), SPI (Serial Peripheral Interface), and I2C (Inter-Integrated Circuit). These interfaces allow the microcontroller to communicate with other devices such as sensors, displays, and other microcontrollers.
• Timers and PWM: It has three timers/counters and six PWM (Pulse Width Modulation) channels, which can be used for generating accurate time delays, measuring external events, and controlling the intensity of analog output signals.
• Power Management: The ATmega328 offers various power-saving modes to optimize power consumption, making it suitable for battery-operated applications.
• Development Tools: Several development tools and software are available for programming and debugging ATmega328, including the Arduino IDE, which provides an easy-to-use platform for beginners.

Ⅴ How to Use ATMega328P using Arduino

Since ATmega328P is used in Arduino Uno and Arduino nano boards, you can directly replace the Arduino board with an ATmega328 chip. For that first, you need to install the Arduino bootloader into the chip (Or you can also buy a chip with a bootloader – ATMega328P-PU). This IC with a bootloader can be placed on an Arduino Uno board and burn the program. Once the Arduino program is burnt into the IC, it can be removed and used in place of the Arduino board, along with a Crystal oscillator and other components as required for the project. Below is the pin mapping between Arduino Uno and the ATmega328P chip.

Figure4-pin mapping

Ⅵ How to Program ATmega328P with Bootloader on Arduino Uno?

Materials Needed

• Arduino Uno
• ATmega328P

Introduction

If you buy a brand new ATmega328P, and you want to program it, a natural way to do it is to unplug the chip that was plugged into the board, and plug in the new chip so that it can be programmed.

Figure5- ATmega328P

Figure6-Arduino Uno

Regretfully, this plan fails because the ATmega328P chip is programmed by the Arduino Uno via the onboard serial port; however, the new ATmega328P lacks the internal Bootloader functionality that is required to program the ATmega328P chip via the serial port.

Therefore, it is necessary to program the Bootloader into the ATmega328P first.

Step1: Program the Bootloader

The Arduino Uno can function as a programmer (ISP) and can be used to program the new ATmega328P's bootloader.

The Arduino Uno can be made into a programmer by downloading the "ArduinoISP" code included with the Arduino IDE to it:

Figuure7-Choose ArduinoISP

Step2: Program the Arduino Uno with the programmer

Before programming starts, connect the hardware as shown in the figure below:

Figure8-Hardware  connection

Step3:Hardware connection when programming Bootloader

Keep in mind that pin 10 of the programmer's Arduino Uno is linked to the target board's RESET pin.

Select Arduino as a programmer in Arduino IDE:

Figure9-Arduino IDE

Step4: The programmer selects Arduino as ISP

Select "Arduino Uno" for the development board in the Arduino IDE. Click "Burn Bootloader" in the menu:

Figure10-Arduino Uno

Once the fire has begun to burn, the prompt reads:

Figure11-burning bootloader

Following a successful burning, the following prompt appears:

Figure12-prompt

Step5: Download Program

After programming the Bootloader, you can program the ATmega328P that has been programmed with the Bootloader through the serial port that comes with the Arduino Uno board. Before programming, you need to remove the ATmega328p on the Arduino Uno board as a programmer. It is the same as inserting the ATmega328P into the Arduino Uno development board to program it. The hardware connection is as follows:

Figure13- Bootloader

Step6: Hardware connection when programming the Flash program

In the Arduino IDE, write a program to blink an LED and choose "ArduinoISP" as the programmer:

Figure14-ArduinoISP

Step7: Select Programmer ArduinoISP

Then, you can download the program normally.

Ⅶ Applications

There are hundreds of applications for ATMEGA328P:

• utilized in boards such as the Arduino Micro, Nano, and UNO.
• Industrial control systems.
• SMPS and Power Regulation Systems.
• Digital data processing.
• Analog signal measuring and manipulations.
• vending machines and coffee makers
• Motor control systems.
• Display units.
• Peripheral Interface system.

Ⅷ ATmega328P Datasheet

ATmega328P Datasheet