CodePudding user response:

Not clear, the compiler doesn't know USART3_4IRQn method name,
See you hang the interruption of library library.. The definition of H should do not have this name,

CodePudding user response:

Resolved, the original is to choose something I'm not in the header file microcontroller

CodePudding user response:

How to choose the required microcontroller in the header file?