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PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor
9-1
Chapter 9
Boot Assist Module (BAM)
9.1
Introduction
The PXN20 boot assist module (BAM) is a 4 KB block of read-only memory (ROM) that is programmed
by Freescale using variable length encoding (VLE) code. The BAM program is executed by the e200z6
when the PXN20 performs a power-on-reset (POR) or any other reset for which the CRP_Z6VEC register
remains in its reset state. The BAM program provides MCU initialization. It also transitions to the user
application code that resides in the internal flash or downloads the user code into internal RAM via CAN
or SCI serial links and passes control to the user code.
9.1.1
Features
The BAM program provides the following functionality:
•
Initial e200z6 core MMU setup with no address translation for all internal MCU resources and
external memory address space
•
Location and detection of user boot code in the internal flash
•
Automatic switch to serial-boot mode if internal flash is blank or invalid
•
Supports user programmable 64-bit password protection for serial-boot mode
•
Supports serial bootloading via CAN bus or eSCI to the internal SRAM
•
Supports censorship protection for internal flash memory
•
Provides an option to disable the error correction status module (ECSM) software watchdog timer
(enabled by default)
•
Configures MMU boot block to boot as either classic Power Book E code or as Freescale VLE
code, allowing transition to the user code with classic Power Book E instructions or VLE
instructions
NOTE
The BAM program is intended to be run on e200z6 (main core) only.
Attempting to execute the BAM program by the e200z0 core may cause
erratic MCU behavior.
NOTE
During BAM program execution, the default reset values of various system
registers (e.g. SIU, FlexCAN, eSCI, ECSM, SWT) may be updated from
their default reset values.
Содержание PXN2020
Страница 1: ...PXN20 Microcontroller Reference Manual Devices Supported PXN2020 PXN2120 PXN20RM Rev 1 06 2011...
Страница 42: ...PXN20 Microcontroller Reference Manual Rev 1 lxiv Freescale Semiconductor...
Страница 64: ...Introduction PXN20 Microcontroller Reference Manual Rev 1 1 22 Freescale Semiconductor...
Страница 112: ...Signal Description PXN20 Microcontroller Reference Manual Rev 1 3 44 Freescale Semiconductor...
Страница 118: ...Resets PXN20 Microcontroller Reference Manual Rev 1 4 6 Freescale Semiconductor...
Страница 162: ...Clocks Reset and Power CRP PXN20 Microcontroller Reference Manual Rev 1 6 30 Freescale Semiconductor...
Страница 182: ...Frequency Modulated Phase Locked Loop FMPLL PXN20 Microcontroller Reference Manual Rev 1 7 20 Freescale Semiconductor...
Страница 268: ...Boot Assist Module BAM PXN20 Microcontroller Reference Manual Rev 1 9 14 Freescale Semiconductor...
Страница 318: ...Interrupts and Interrupt Controller INTC PXN20 Microcontroller Reference Manual Rev 1 10 50 Freescale Semiconductor...
Страница 326: ...General Purpose Static RAM SRAM PXN20 Microcontroller Reference Manual Rev 1 11 8 Freescale Semiconductor...
Страница 372: ...e200z6 Core Z6 PXN20 Microcontroller Reference Manual Rev 1 13 8 Freescale Semiconductor...
Страница 412: ...e200z0 Core Z0 PXN20 Microcontroller Reference Manual Rev 1 14 14 Freescale Semiconductor...
Страница 460: ...Memory Protection Unit MPU PXN20 Microcontroller Reference Manual Rev 1 18 20 Freescale Semiconductor...
Страница 478: ...Error Correction Status Module ECSM PXN20 Microcontroller Reference Manual Rev 1 19 18 Freescale Semiconductor...
Страница 488: ...Software Watchdog Timer SWT PXN20 Microcontroller Reference Manual Rev 1 20 10 Freescale Semiconductor...
Страница 494: ...System Timer Module STM PXN20 Microcontroller Reference Manual Rev 1 21 6 Freescale Semiconductor...
Страница 821: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 Freescale Semiconductor 27 49...
Страница 822: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 27 50 Freescale Semiconductor...
Страница 926: ...Controller Area Network FlexCAN PXN20 Microcontroller Reference Manual Rev 1 29 42 Freescale Semiconductor...
Страница 990: ...Deserial Serial Peripheral Interface DSPI PXN20 Microcontroller Reference Manual Rev 1 30 64 Freescale Semiconductor...
Страница 1044: ...Enhanced Serial Communication Interface eSCI PXN20 Microcontroller Reference Manual Rev 1 31 54 Freescale Semiconductor...
Страница 1080: ...Cross Triggering Unit CTU PXN20 Microcontroller Reference Manual Rev 1 33 12 Freescale Semiconductor...
Страница 1134: ...Analog to Digital Converter ADC PXN20 Microcontroller Reference Manual Rev 1 34 54 Freescale Semiconductor...
Страница 1150: ...IEEE 1149 1 Test Access Port Controller JTAGC PXN20 Microcontroller Reference Manual Rev 1 35 16 Freescale Semiconductor...
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Страница 1376: ...Memory Map PXN20 Microcontroller Reference Manual Rev 1 A 118 Freescale Semiconductor...