Forum: System Workbench for STM32

timer3 counter period. have to be a variable

hello,
when i configurate in MX timer3, i have to fill in for counter period a number, let say 1000.
but i need in my code a variable named: stepper_speed
so in time.c i changed 1000 for stepper_speed.
but every time when i go to MX, and after a change i go back, the code will build op again and change stepper_speed back to 1000.
do anyone nows ho i can avoid this ?
thanks in advanced.