M7 core works but not M4

[Jad]

good morning, I began today on a nucleo 144 and so discovered the double core.

so I wanted to make each core work independently, and used a led blinking code. unfortunately, it only works on core M7 and not on core M4. I do not know why, maybe I misunderstood the fact that we have 2 cores.

[Jad]

it just worked, my flash maybe didn't work well the 2 first times