Arduino for STM32

Hi, I'm new to STM32, I'm trying to start this DC water pump in my project (https://e-radionica.com/hr/mini-pumpa-za-vodu.html) I use STM32F103C8T6, I connected black wire of the pump to the GND of the STM and red one to pin A15. I tried this simple code to turn pump on (pump works fine when not ...

Hello everyone, my name is Eugen I'm 21 years old student and I come from Croatia, I'm using stm32f1 bluepill board for my upcoming projects.