12.1 Overview

The boot ROM ensures the integrity of the device at boot.

An immutable boot sequence (Secure Boot Code) is implemented into a ROM called the secure boot ROM. The secure boot ROM manages system initialization, firmware, data authentication and necessary system configurations.

For secure boot support on the PIC32CX-BZ3/PIC32CX-BZ36, a 64K ROM is dedicated to the secure boot firmware. Keys, unique device ID, storage key and secure boot key required for code authentication are stored as a part of eFuses. On every reset, secure boot firmware authenticates the rest of the program image in the Flash.

Note: The default clock FRC is 8 MHz and jumps to 64 MHz. In addition, the boot ROM has extra security features, such as device integrity checks, memory/peripherals security attributions, and secure boot, which can be executed before jumping to the Flash in the Secure state.