Boot Assist Module (BAM)MPC5566 Microcontroller Reference Manual, Rev. 216-2 Freescale Semiconductor16.1.2 FeaturesThe BAM program provides the following features:• Initial e200z6 core MMU setup with minimum address translation for all internal MCU resourcesand external memory address space• Locate and detect application boot code• Automatic switch to serial boot mode if internal or external flash is not initialized or invalid• Programmable 64-bit password protection for serial boot mode• Boot application code from:— Internal flash module— external memory without arbitration— external memory with arbitration• Serial boot loads the application boot code from a FlexCAN or eSCI bus into internal SRAM• Censorship protection for internal flash module• Enable the e200z6 core watchdog timer• Configurable memory map for use with the classic PowerPC Book E code or Freescale VLE code• Configurable external data bus for 16- or 32-bit wide (416 and 496 PBGA packages only)16.1.3 Modes of Operation16.1.3.1 Normal ModeIn normal operation, the BAM responds to all read requests within its address space. The BAM programis executed following the negation of reset.16.1.3.2 Debug ModeThe BAM program is not executed when the MCU comes out of reset in OnCE debug mode. Use thedevelopment tool to configure and initialize the MCU before accessing the MCU resources.16.1.3.3 Internal Boot ModeUse internal boot mode to boot from internal flash memory. Configuration information, initialization, andboot code are kept in internal flash. The BAM program must complete the boot process before applicationcode can enable the external bus interface.16.1.3.4 External Boot ModesUse external boot mode when the boot code and configuration information are located in external memorythat is connected to the EBI. Enable bus arbitration for multiprocessor systems to allow a boot option. Donot select external boot mode for devices without an external bus.
