7.6.2 Initial Instructions Fetching

After reset is released, the CPU starts fetching from the Boot Flash (BFM).

Unless a debugger is connected and places the Boot Flash (BFM) in a specific mode called Boot Interactive mode, the CPU will jump to the Flash memory loading the Program Counter (PC) and Stack Pointer (SP) values and start fetching Flash user code. Before jumping to the Flash, the Boot Flash (BFM) resets the two first 2 kB of SRAM. The Clocks remain unchanged.

Note: The PIC32CK SG/GC Boot Interactive mode allows a debugger to perform several actions on the device, such as NVM areas integrity check, chip erase, and so on. Refer to the “Boot Flash (BFM)” section for more information.

In addition, the PIC32CK SG/GC Boot Flash (BFM) has extra security features, such as device integrity checks, memories and peripherals security attributions, and secure boot that can be executed before jumping to the Flash in Secure state.