pwm signal on a gpio pin using tim1 and dma on a blackpill board stm32f401
libopencm3 as HAL
RM 0368 Reference manual STM32F401xB/C and STM32F401xD/E advanced Arm®-based 32-bit MCUs
STM32F401xB STM32F401xC Arm® Cortex®-M4 32-bit MCU+FPU, 105 DMIPS, 256KB Flash / 64KB RAM, 11 TIMs, 1 ADC, 11 comm. interfaces
os : windows
make, gcc & friends : https://xpack.github.io/dev-tools/arm-none-eabi-gcc
ide : https://www.eclipse.org
shell : https://www.cygwin.com
st-link : https://www.st.com/en/development-tools/st-link-v2.html, alixepress