Whaaat?? How To Extract HEX Code from Arduino
Introduction
When working with microcontrollers, it is important to understand their memory structure and how code is stored and executed. In this article, we will focus on the program memory of microcontrollers, specifically the Arduino Uno, and learn how to extract the code stored in the flash memory.
Understanding Arduino and its Code
Arduino is a popular open-source electronics platform that is commonly used by hobbyists and professionals alike to create interactive projects. While many refer to the board itself as an Arduino, it’s important to note that Arduino is actually a software and a community that supports various microcontroller boards.
Extracting Code from Arduino
If you’ve ever wanted to extract code from an Arduino board, perhaps to backup your existing projects or to understand how a particular project works, it is possible to do so. Instead of writing code to the Arduino, you can extract an existing code from it and save it in a hexadecimal format, which is essentially a sequence of ones and zeros.
Understanding the Storage and Burning Process
Before we dive into the extraction process, let’s briefly understand how the code is stored and burned to the Arduino. The Arduino board consists of a microcontroller, which is responsible for executing the code. The code is typically written using the Arduino IDE (Integrated Development Environment) and then uploaded to the board using a USB cable.
Software for Code Extraction
To extract the code from an Arduino, you’ll need specific software. One popular tool for this purpose is avrdude, which is a command-line utility. Avrdude allows you to communicate with the microcontroller on the Arduino board and read the code stored in its memory. You can find avrdude and related software libraries online, usually as part of the Arduino software package.
Writing the Extractor Code back to Arduino
Once you have successfully extracted the code from the Arduino, you may be interested in writing it back to the board. This can be done using the avrdude utility as well. By specifying the appropriate flags and options, you can upload the extracted code to the Arduino, essentially restoring it to its previous state.
The Anatomy of an Arduino: Understanding the Microcontroller
The Arduino is a widely popular development board used by hobbyists, makers, and professionals alike. But have you ever wondered what exactly the Arduino is made of? In this article, we will delve into the inner workings of the Arduino, specifically focusing on the microcontroller that powers it.
An Introduction to Microcontrollers
Before we dive into the details, it is important to understand the concept of a microcontroller. A microcontroller is a small computer on a single integrated circuit. It consists of a central processing unit (CPU), memory, and input/output peripherals, all on a single chip. Microcontrollers are designed to execute specific tasks and are typically used in embedded systems.
The Arduino Development Board
When we talk about the Arduino, we are actually referring to the development board itself. The Arduino board is composed of a printed circuit board (PCB) with plastic pins, voltage regulators, connectors, and various other components. However, the real microcontroller, the brains of the Arduino, is a separate chip.
Understanding the Mega 228p Microcontroller
The most commonly used microcontroller in Arduino boards is the Mega 228p, which is manufactured by a company called Atmel (now acquired by Microchip Technology). The Mega 228p belongs to a family of microcontrollers known as AVR (Alf and Vegard’s RISC processor) chips.
The Structure of an AVR Microcontroller
Inside the AVR microcontroller, we have the main CPU, flash memory, eeprom (electrically erasable programmable read-only memory), and SRAM (static random-access memory). This means that for most applications, an external memory is not required.
Expanding Memory with External Devices
However, if you need more memory for your project, you can connect external memory devices to the AVR microcontroller. Many AVR chips, such as the ATtiny85, have a serial interface that can be used to connect larger eeproms or flash modules. These external memories come in the form of separate chips and can greatly expand the storage capacity of the microcontroller.
The Role of Flash Memory
The program instructions that we upload to the Arduino are stored in a type of non-volatile memory called flash memory. This means that even when power is removed, the program will remain stored in the flash memory, allowing the microcontroller to execute the code upon power-up.
The Size of Program Memory
Microcontrollers typically have limited program memory, and this size is usually indicated in the device’s name. For example, the atmega 64x has 64 kilobytes of flash memory, while the Arduino Uno uses the Mega 32x, which has 32 kilobytes of flash memory. Unlike some microcontrollers, these do not have external program memory, meaning all the code executed by the AVR core must be stored within the chip on its flash memory.
Focusing on Program Memory
Within the Arduino Uno, there are several types of memory, including program memory, data memory, and eprom. For the purpose of this tutorial, we will focus solely on the program memory. This memory is divided into two sections: the boot flash section and the rest of the code. For now, we will not be concerned with the boot section, so our code will be stored in the remaining section.
Compiling the Code
When writing Arduino code, it is important to note that the code itself is not stored in a plain text format. Instead, the compiler takes the code and translates it into zeros and ones, which are then stored in the memory. This process, known as binary data, is what we are interested in extracting.
Understanding the Binary Data
To better understand the binary data, let’s take an example using the Blink code. When this code is programmed to the microcontroller chip, it is stored as binary data in hexadecimal format. This binary data represents the instructions that the chip will execute when running the Blink code. By extracting this binary data, we can analyze and compare it with the uploaded code later.
Using Arduino ISP to Program an Arduino
Programming an Arduino can be done easily using a USB connection. However, in some cases, the USB connector may not be available or cannot be used. In such situations, an ISP (In-System Programming) communication method can be used to program the Arduino.
Setting Up the Arduino ISP
To use the Arduino ISP, you will need to upload a specific software called AVR to your Arduino board. Start by preparing two Arduino boards – one will be the master and the other will be the one you want to program.
Connect the master Arduino to your PC and run the Arduino IDE. Go to File, then Examples, and select Arduino ISP. Open the example code, select the appropriate Arduino board, compile, and upload the code to the master Arduino. This will set up the Arduino as an ISP programmer.
Connecting the Master Arduino to the Target Arduino
Next, you will need to make the necessary connections between the master Arduino and the Arduino you want to program. These connections are specific to ISP communication and can be found in the ISP communication pinout diagram.
If you have an ISP programmer, you can use it to easily make the connections. However, if you don’t have one, you can use another Arduino as a controller to bridge the connection between the master Arduino and the target Arduino. In this case, the master Arduino will act as the ISP programmer.
Using the AVR Software
Now, it’s time to use the AVR software to program the target Arduino. Download and install the AVR software on your computer. Make sure the master Arduino is connected to your PC via USB.
Open the AVR software and select the Arduino as the programmer. In the COM list, select the COM port of your master Arduino. This will establish communication between the AVR software and the master Arduino.
With the connection established, you can now upload the desired code to the target Arduino using the AVR software. Simply select the code you want to upload, compile it, and program the target Arduino using the ISP communication method.
Exploring the Configuration of Microcontrollers for Arduino
Microcontrollers play a crucial role in the functioning of Arduino boards. These tiny chips control various aspects of the Arduino, such as its clock sources, memory, and configuration settings. In this article, we will delve into the world of microcontroller configuration and understand how to access and retrieve important values.
Setting the Communication Rate
When working with microcontrollers, it is essential to establish the correct communication rate. The rate is usually defined in bits per second and is known as the baud rate. For instance, in this case, the baud rate is set to 19200, but it may vary depending on the model you are using. Some models operate at a different speed, typically 115 200. Adjust the rate accordingly to ensure proper communication between the master Arduino and the code Arduino.
Identifying the Microcontroller
To access the microcontroller’s configuration settings, we first need to select the appropriate microcontroller unit (MCU). For Arduino Uno, the recommended MCU is atmega 228p. By clicking on the “detect” button, we can verify if the ISP connection between the master and code Arduino is functioning correctly. A successful connection will display a confirmation message.
Understanding Fuse Bytes
In the world of microcontrollers, fuses act as switches that control various parameters and configurations. These fuses can be either 0 or 1 and determine the behavior of the microcontroller. The Arduino’s microcontroller has multiple types of fuses, including low fuse byte, high fuse byte, extended fuse byte, and lb fuses.
The low fuse byte is responsible for managing clock sources, and each bit controls a specific aspect. By examining the low fuse byte, we can determine the clock source being used. Similarly, the high fuse byte controls critical components like the reset mechanism, Watchdog timer, and bootloader memory.
Retrieving Fuse Values
If an Arduino code has modified any of these fuse bits, it is crucial to retrieve their values for future reference. To obtain these values, we can utilize AVR software. By clicking on the “read” button next to the fuse bits, we can obtain the current configuration values. However, it is important to note that there is no built-in storage mechanism within the software to store these values permanently.
To ensure you don’t lose these crucial configuration values, it is advisable to write them down. You can create a notepad file or use any other method to store and document these values for future use. This way, if any modifications are made to the microcontroller’s configuration, you will have a reference of the original settings.
Understanding and accessing the configuration settings of microcontrollers are essential for working with Arduino boards. By familiarizing ourselves with fuse bytes and retrieving their values, we can maintain a record of the microcontroller’s original configuration and make informed modifications when necessary.
Extracting Code from Arduino
So you’ve built your project on an Arduino board and now you want to extract the code from it. Whether it’s to make changes, save a backup, or simply understand how it works, extracting the code is an essential step. In this article, we’ll guide you through the process of extracting code from an Arduino, step by step.
Extracting Code from Flash Memory
The first step in extracting the code is to mark the recheck box for the flash memory. This tells the Arduino to include the code stored in its flash memory when extracting. Additionally, you need to select the appropriate format, which is usually the Intel hex format for hexadecimal code. Next, click on the three dots button to choose where you want to save the code file. Give it a name that is relevant to your project. For example, if your project blinks an LED every 100 milliseconds, you could name it “blink_100ms.hex”. Once you’ve selected the location and provided a name, click the Go button. The code will now be extracted from the Arduino’s blue board.
Extracting Code from EEPROM Memory
In some cases, your code may utilize the EEPROM (electrically erasable programmable read-only memory) for storing certain settings or data. If your project involves the EEPROM, you will also need to extract code from this memory. To do so, mark the read checkbox for the EEPROM memory, similar to how we did for the flash memory. Then, click on the three dots button to select a location to save the extracted file. Name it accordingly, such as “eprom100ms.data”. Finally, click the Go button to extract the EEPROM data file from the Arduino.
The Importance of Extracting EEPROM
You may be wondering why it’s necessary to extract the EEPROM data if your code is already extracted from the flash memory. The reason lies in the specific requirements of your project. Certain codes may utilize the EEPROM for storing valuable settings or user-defined data. For example, in a soldering iron project, the user settings may be saved in the EEPROM. Therefore, if you want to have a complete copy of the code, it’s important to extract the EEPROM memory as well.
Verifying Extracted Code
To ensure that the extracted code works as expected, it’s always wise to verify it. Connect your blue Arduino board to your computer and open the Arduino IDE (Integrated Development Environment). Upload the extracted code onto the Arduino, making sure to select the appropriate board and port. In this example, we’ll upload a code that blinks an LED every two seconds. Once the code is uploaded successfully, you can observe the blinking LED as confirmation that the code extracted from the Arduino is working properly.
A Step-by-Step Guide to Copying and Uploading Code to your Arduino
If you are an Arduino enthusiast, you know the thrill of exploring new codes and programming your Arduino board. However, what if you come across a code that you want to copy and upload to a different Arduino board? In this article, we will guide you through the process of extracting and uploading code from one Arduino to another. Let’s get started!
Step 1: Slowing down the LED Blink
Before we dive into the code extraction process, let’s first slow down the LED blink on the Arduino. This will serve as a visual confirmation of the code transfer progress. Connect the blue Arduino back to the master Arduino using ISP connections. Once connected, navigate to the AVR software and ensure that the following settings are selected in the flash part.
Step 2: Selecting the Hexadecimal File
In the flash part, select the appropriate options and then choose the hexadecimal file that you extracted earlier from your PC folder. Additionally, mark the race, flash, and eprom checkboxes. Finally, click on the “Go” button to initiate the code transfer process. The new code will be uploaded to the blue Arduino in a matter of minutes.
Step 3: Disconnecting the Reset Wire
Once the code transfer is complete, remove the reset wire or disconnect all the SP pins and reset the Arduino. This step ensures that the newly uploaded code takes effect. After completing this step, you will notice a significant change in the LED blink rate, now programmed to blink every 100 milliseconds instead of the previous two seconds.
Step 4: Reuploading the Full Code
If you wish to fully copy and upload a code, you need to reupload all the parts. Retrieve the fuse values from your notepad file and input them into the software. Check the “Set Fuse” checkbox and select the xlsmo file of the code. Ensure that the correct checkboxes are selected for the eprom file as well. Double-check all the settings to ensure they match your MCU type and speed. Don’t forget to also check the “Erase Flash and Eprom” checkbox. Once everything is set, click on the “Program” button.
Step 5: Successful Code Transfer
With just a few simple steps, you have successfully copied and uploaded the code from your Arduino to the blue Arduino. It is important to note that during this process, you only have access to the hexadecimal format of the code. Nevertheless, armed with this knowledge, you can now freely experiment and customize codes on different Arduino boards to your heart’s content!
The Limitations of Editing Code in the Arduino IDE
Many Arduino enthusiasts are familiar with the Arduino IDE, a software tool used for writing and uploading code onto Arduino boards. While the Arduino IDE provides a convenient platform for coding, there are limitations when it comes to editing code directly within the software. In this article, we will explore the restrictions and alternative options for modifying code in the Arduino IDE.
No Direct Editing Allowed
One major drawback of the Arduino IDE is the inability to directly edit code within the software. Unlike other Integrated Development Environments, such as Visual Studio or Eclipse, the Arduino IDE does not offer features like code highlighting, autocomplete, or refactoring. This means that making changes or fixing bugs in existing code can be a tedious and time-consuming process.
Copy and Upload
Although you cannot edit code directly in the Arduino IDE, there is a workaround available. You can simply copy the code you want to modify, make the necessary changes using a text editor or an external IDE, and then upload the modified code back to your Arduino board. This process allows you to make edits outside of the Arduino IDE without losing the functionality of the software.
Compatible Arduino Boards
The copy and upload method works with various Arduino boards, including the Arduino Uno, Arduino Nano, and even the Atmega 320 chip soldered to a prototyping board. As long as you have access to the ISP (In-System Programming) pins on the Arduino board, you can modify the code using the aforementioned process.
Expand Your Options
If you find the limitations of the Arduino IDE hindering your coding experience, there are alternative options available that provide more comprehensive features for editing code. Explore other IDEs such as PlatformIO, Eclipse Arduino IDE, or Visual Studio Code with the Arduino extension. These tools offer a range of functionalities that can enhance your coding capabilities and make the editing process more efficient.
Wrap Up
While the Arduino IDE is a popular platform for coding Arduino boards, it does have its limitations when it comes to editing code directly within the software. However, by copying and uploading the code back onto the Arduino board, you can make modifications outside of the Arduino IDE. Additionally, there are alternative IDEs available that offer more advanced features for editing code. So, don’t let the limitations hold you back and explore the options to enhance your Arduino coding experience!
Extracting code from an Arduino board can be a valuable skill to have, especially when you want to understand or backup your projects. By using software like avrdude, you can extract the code from the Arduino and even write it back if desired. Remember to always follow proper procedures and precautions when working with electronics to avoid any damage.
So, the next time you hear the term “Arduino,” remember that it refers to the entire development board, but the microcontroller itself is a separate chip. Understanding the anatomy of an Arduino and how its microcontroller works is essential for anyone venturing into the world of microcontroller programming. Whether you’re a beginner or an experienced developer, Arduino’s versatility and ease of use make it an ideal platform for bringing your projects to life.
In this article, we have explored the program memory of microcontrollers, focusing on the Arduino Uno. We have learned that the code is stored as binary data in the flash memory of the microcontroller chip. By extracting this binary data, we can gain insights and compare it with the uploaded code. Understanding the memory structure and how the code is stored and executed is crucial for working effectively with microcontrollers.
Using Arduino ISP to program an Arduino provides an alternative method when USB connection is not feasible. By setting up the master Arduino as an ISP programmer and making the necessary connections, you can easily program the target Arduino using the AVR software. This opens up new possibilities for programming Arduino boards in various situations.
Extracting code from an Arduino board can be a valuable process for a variety of reasons. By following the steps outlined in this article, you can easily extract the code from both the flash and EEPROM memories. Remember to consider the specific requirements of your project, as certain codes may utilize the EEPROM for critical data. Verifying the extracted code ensures that it functions as intended. So, go ahead and extract that code from your Arduino board and dive into the world of tinkering and experimentation!
Copying and uploading code from one Arduino board to another may seem daunting at first, but with the right knowledge and steps, it becomes a straightforward process. By following the instructions outlined in this article, you can successfully transfer codes and make your Arduino projects even more versatile and exciting. So go ahead, unleash your creativity, and start exploring the endless possibilities of Arduino programming!
