How to Program Flash Memory with Segger J-Link and J-Flash
If you are looking for a fast and reliable way to program flash memory on your ARM-based devices, you might want to consider using Segger J-Link and J-Flash. Segger J-Link is a debug probe that supports a wide range of ARM cores and devices, and offers high-speed communication, advanced breakpoints, and real-time tracing. Segger J-Flash is a software tool that allows you to program flash memory on supported devices using J-Link, either for development or production purposes.
In this article, we will explain how to use Segger J-Link and J-Flash to program flash memory on your ARM devices, and what are the benefits and limitations of each method. We will also show you how to avoid common pitfalls and errors that might occur when using these tools.
What is Flash Memory and Why Do You Need to Program It
Flash memory is a type of non-volatile memory that can retain data even when the power is turned off. It is commonly used to store firmware, bootloaders, configuration settings, and user data on embedded devices. Flash memory can be divided into two main types: internal flash and external flash.
Internal flash is flash memory that is integrated into the microcontroller or microprocessor chip. It usually has a fixed size and address range, and can be accessed directly by the CPU. Internal flash is often used to store the main application code and critical data that need to be protected from corruption or tampering.
External flash is flash memory that is connected to the microcontroller or microprocessor via a peripheral interface, such as SPI, QSPI, or parallel CFI. It usually has a larger capacity and can be mapped into the CPU address space or accessed indirectly by commands. External flash is often used to store additional code, data, or resources that need more space or flexibility.
To program flash memory on your ARM devices, you need a tool that can communicate with the device, erase the flash sectors, write the data into the flash memory, and verify the correctness of the data. You also need a tool that can support different types of flash memory, different device architectures, and different programming modes.
What is Segger J-Link and How Does It Work
Segger J-Link is a debug probe that connects to your ARM device via a JTAG or SWD interface. It allows you to debug your application code, set breakpoints, watch variables, inspect registers, and perform other debugging tasks. It also allows you to program flash memory on your device using built-in flash loaders that are highly optimized for speed and reliability.
To use Segger J-Link to program flash memory on your device, you need to connect it to your PC via USB and to your device via JTAG or SWD. You also need to install the J-Link software package on your PC, which includes drivers, utilities, documentation, and examples. You can then use one of the following methods to program flash memory:
J-Link Commander: This is a command-line tool that allows you to execute various commands related to J-Link and flash programming. You can use commands like loadbin or loadfile to load binary or hex files into the flash memory of your device.
J-Flash Lite: This is a graphical user interface tool that allows you to select your device model, specify the file name and address of the data to be programmed, and start the programming process with a single click.
J-Link SDK: This is a software development kit that allows you to integrate J-Link functionality into your own applications. You can use the J-Link API functions to control J-Link and program flash memory on your device programmatically.
Third-party IDEs: Many integrated development environments (IDEs) support J-Link as a debug probe and offer flash programming features. You can use your preferred IDE to write your code, compile it, download it into the flash memory of your device, and debug it.