Modern machine control systems increasingly rely on graphical touch displays instead of simple text or symbol indicators. As display sizes increase, typically from 3.5 inches upwards, the demands on the microcontrollers used grow significantly, particularly concerning processing power, RAM, and Flash memory.
The STM32H7xx series from STMicroelectronics provides a powerful platform for the efficient implementation of demanding graphical user interfaces. Featuring an integrated TFT controller, ample internal RAM, and high-speed external SPI Flash connectivity, it unlocks new possibilities for flexible HMI solutions.
Solution Highlights
External SPI Flash
STM32H7 controllers support the use of external SPI Flash in QuadSPI mode, achieving significantly higher data rates compared to conventional SPI. Of particular note is the XiP (Execute in Place) mode, where the external Flash is treated as internal memory, making it ideal for rendering fonts, icons, or images.
Bootloader for Field Updates
A customizable bootloader enables secure over-the-air updates for devices in the field, for instance, by separating the internal boot area from the external application. This also allows for future variants with different touch ICs or displays to be supported.
GUI Design with TouchGFX
The user interface is implemented using TouchGFX, a powerful framework for GUI development based on STM32. TouchGFX facilitates resource-efficient designs through targeted reduction of fonts or image formats.
Conclusion
The combination of STM32H7, external QSPI Flash, and TouchGFX forms a flexible, cost-efficient platform for demanding HMIs. This solution is scalable, future-proof, and allows for individual customization, making it ideal for industrial control systems or OEM applications.
