fignrerprintfignrerprintaxf Error L6200E Symbol HAL_TIM_PeriodElapsedCallback multiply defined by beepero and maino

This error occurs when the same symbol (in this case, HAL_TIM_PeriodElapsedCallback) is defined in multiple object files (beeper.o and main.o). This can happen when the same function is included in multiple source files that are compiled and linked together.

To fix this error, you need to ensure that the symbol is only defined once. One way to do this is to move the function definition to a separate source file and only include it in the object files that require it. Alternatively, you can use the static keyword when defining the function to limit its scope to the current source file.

Once you have resolved the multiple definition issue, you can recompile and link your program to generate the final binary file