ST recently launched the STLINK-V3, a complete architectural overhaul of its in-circuit debugger/programmer for STM8 and STM32 microcontrollers (MCU). In a nutshell, the new device is able to transfer data faster and with a lot more flexibility, thanks in part to a new system that allows the addition of extension cards. At its core, the STLINK-V3SET, the dedicated module housing the STLINK-V3 technology, builds on one fundamental lesson that we learned with the previous generation of products: the debugger will find itself in a vast number of unanticipated situations, and it’s up to us to make sure users can still take full advantage of this solution, even in unexpected edge cases or new applications. This is why the architecture of the new in-circuit debugger/programmer focuses on increasing its versatility.
1. A Strong Heritage
The previous generation of ST-LINK/V2 family of products remains highly popular and diverse. The first standalone device came out in 2011 and meant that developers could quickly and easily connect the in-circuit debugger/programmer between their board and their PC to compile their code, send their application to their MCU, and figure out if it would run or if an error could cause problems. We know that the solution is highly popular amongst professionals and large engineering teams, which is why we will continue to sell and support our ST-LINK/V2 devices. We are deploying our new STLINK-V3SET, but we also understand that some may want to continue to use something that’s familiar to them.
Furthermore, the family of ST-LINK/V2 products extends far beyond the standalone models as there are third-party variants with different form factors that remain quite popular. There’s also an ST-LINK/V2 directly integrated into our development solutions, like on the STM32 Discovery kits or Nucleo boards, and that we optimized for the Serial Wire Debug (SWD) interface with a small footprint. One of its features is the mass storage support that ensures users simply need to open a storage volume on their PC to drag-and-drop binaries instead of going through an IDE to start uploading their application.
2. A Faster In-Circuit Debugger/Programmer
Data transfers are the bread and butter of this platform, which explains why the first major architectural difference between the ST-LINK/V2 and STLINK-V3S is the latter’s compatibility with the USB 2.0 Hi-Speed interface. Previously, developers had to contend with a 12 Mbit/s USB 2.0 Full-Speed data rate, which could be cumbersome when uploading large applications. The new model now offers theoretical speeds of up to 480 Mbit/s, which will result in a drastically faster experience. Furthermore, beyond the simple interface upgrade, ST also implemented multiple optimizations of its algorithms and processes, making this a thorough architectural overhaul instead of a simple speed bump. Hence, the increase in productivity for teams that upload very large applications multiple times a day is highly noticeable.
Beyond better speed, the new the STLINK-V3SET now offers mass storage support to allow for a much more convenient upload process. Until now, only the ST-LINK/V2 present on some of our development boards, such as all our Nucleo boards, offered this feature. However, with the new models, engineers will be able to connect the in-circuit debugger/programmer, then drag and drop binaries to upload them in no time. This is particularly useful for developers wanting to quickly experiment with a demo application on a custom PCB, and who would rather not have to compile their code and send it through their IDE. It also makes swapping demos far more convenient, especially when teams are in the field.
3. A More Flexible Tool
This new level of practicality is made possible by the ST 14-pin debug connector that we call STDC14. When users open the box of the STLINK-V3SET they’ll find a multitude of cables to fit their needs. Among them, there’s the traditional MIPI 10-pin cable, which is relatively compact and very popular, as well as the larger but still useful MIPI–20. Additionally, we are also introducing a new STDC 14-pin cable. The MIPI 10-pin version doesn’t support a virtual COM port. As a result, we developed an extension of the MIPI–10 connector that uses four additional pins to offer more features.
This is important because until now, engineers had to use extra cables and find workarounds to get a virtual COM port when they didn’t have the ST-LINK/V2 built into their development board. Now, they only need a STLINK-V3SET and a STDC–14 connector. Similarly, the in-circuit debugger/programmer opens the door to an entirely new set of features as it allows PC developers to drive a couple of GPIOs from the new ST-LINK thanks to the DLLs that are planned for release in December. As a result, teams can potentially add LEDs that light up as a sign that a routine performs its job, control other peripherals, or even use proprietary extensions via these IOs.
4. A More Versatile Companion
As we saw, the new architecture offers the same versatility as previous generations, with the possibility of using JTAG (Joint Test Action Group) and SWD for the STM32 MCUs, and SWIM (Single Wire Interface Module) for the STM8. It also adds a tremendous level of flexibility with the possibility of using an STDC–14 connector to benefit from a virtual COM port. However, the new STLINK-V3SET goes even one step further with the ability to add extension cards on the debugger/programmer to increase its functionalities.
For instance, the complimentary interface board allows developers to upload a firmware through the SPI, I2C, or UART interface, this extension card serving as a bridge between the target board and the PC. Using the STM32CubeProgrammer software tool, either in a command line or graphical interface mode, developers can seamlessly use this bridge in their environment to facilitate maintenance operations without leaving a debug port open, which can represent a serious security breach. And to make these cards even more practical, we are offering a height-adjustable casing that will adapt to the size of the stack present on top of the STLINK-V3SET so users can neatly house these cards.
Our new debugger/programmer is a significant step forward, and we can’t wait to see what the community does with it. For instance, Percepio already announced Tracealyzer launch support for STLINK-V3SET. Tracealyzer is the premier trace visualization tool for developers of RTOS-based software systems, providing over 30 graphical views and live visualization. Tracealyzer v4.2 integrates support for STLINK-V3SET, allowing for comprehensive insight into STM32 software during development, debugging, validation, and optimization.