A new device usually requires a flashloader and in some cases also a script defining special connect and reset sequences, required by the device. While SEGGER maintains the updating of J-Link software with new devices, some devices might be left out in the process. To enable customers filling in the gaps on their own, the J-Link DSK is offered. To make creating support as easy as possible, the J-Link DSK comes with the SEGGER Flash Loader (SFL) as well as a set of example script files for various devices that require special handling.
A core component of the DSK is the SEGGER Flash Loader. The SEGGER Flash Loader (SFL) is responsible for the setup of the device for accessing flash memory via the debug interface of the microcontroller. The SFL is a piece of code tailored to the supported device that is temporarily downloaded into RAM. It performs the programming of the flash.
Once an SFL has been added for a new device, it is used by the J-Link flash download feature and flash download is available in all J-Link utilities (J-Link Commander, J-Flash, ...). The SFL also enables the unlimited number of breakpoints in flash feature for the device. Direct download into flash memory via an IDE / Ozone is available as well.
Bottom line: The SFL makes the flash download support behave as if device support had been added by SEGGER directly. For more information about the SFL and how to write an algorithm, please refer to the SEGGER wiki.
Some devices require special connect/reset sequences which are not covered by the generic sequences J-Link uses by default. For such devices, a J-Link script file may be needed to have proper device support in J-Link. The J-Link DSK includes examples of J-Link script files for various devices that require special handling. For more information about J-Link script files in general, please refer to the SEGGER wiki.
Silicon vendors or project managers who have device support files for new devices may require a way to distribute the files that include the support. The files can either be copied to the hard drive of the end user or added by simply running an installer. The J-Link DSK comes with a template for an installer setting this up within Microsoft Windows.
Q: I am not working for a silicon vendor but a company that uses MCUs in their product. Can we still use the J-Link DSK?
A: Yes, the J-Link DSK is available to everyone.
Q: I have an SPI flash connected to my Cortex-M4 based MCU but the SPI flash is not memory-mapped into the MCU address space. Can I still use the DSK + SFL?
A: Yes, the SFL also works with non-memory mapped flash devices. All that needs to be done is the assigning of a "virtual" address to such flash. The J-Link software uses these virtual addresses. The SFL will then map the virtual address to the actual memory access.