Hi @Imen.D
The pins should be push-pull, even if they are inputs. This covers on the Bootloader side from possible noise on the pins.
Sorry, but I don't understand. An input can't be push-pull. Is this requirement on the master device connected to STM32? Then this ought to be said so. (Btw. I think it's the pull-down which is to solve problems with noise; and that's a different thing from "push-pull")
I mean, the state of pins in bootloader (especially those which start automatically when chip is "empty", e.g. pattern 6) really should be perfectly documented, as unexpected pullups/pulldowns - not to mention pins set hard to output - may destroy a new device. In fact, the RM ought to point out this possibility, directing to AN2606 for the details (which then ought to be in AN2606).
JW
