Marlin is a firmware for RepRap 3D printers optimized for both 8 and 32 bit microcontrollers. Marlin supports all common platforms. Many commercial 3D printers come with Marlin installed. Check with your vendor if you need source code for your specific machine.
STM32Cube MCU Full Package for the STM32F4 series - (HAL + LL Drivers, CMSIS Core, CMSIS Device, MW libraries plus a set of Projects running on all boards provided by ST (Nucleo, Evaluation and Discovery Kits))
Platform-independent drivers for STMicroelectronics MEMS motion sensors, environmental sensors, infrared sensors and biosensors, based on standard C programming language.