
Boot Assist Module (BAM)
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor
9-3
9.2.2
Register Descriptions
The BAM module does not have any registers.
9.3
Functional Description
9.3.1
BAM Program Resources
The BAM program uses/initializes these MCU resources:
•
The BOOTCFG field in the reset status register (SIU_RSR) determines the boot option
•
The location and value of the reset configuration halfword (RCHW) determines the location of
boot code and the boot configuration options
•
FlexCAN_A and eSCI _A modules for serial-boot mode
•
FlexCAN_A message buffer RAM for stack and global variables during serial-boot mode
•
The DISNEX bit in the SIU_CCR register to determine if the Nexus port is enabled
The BAM program:
•
Configures the e200z6 MMU to cover all available MCU address space: internal flash, peripheral
bridge, and SRAM without address translation
•
Configures FlexCAN_A, eSCI_A when performing serial-boot mode
•
Uses the eDMA during serial-boot mode.
9.3.2
BAM Program Operation
If the CRP_Z6VEC register value is 0xFFFF_FFFC, the BAM code is executed after the negation of reset
and before user code starts. To prevent the execution of the BAM code when exiting sleep mode, change
the value of the CRP_Z6VEC register before entering sleep mode. See
for more detail about the CRP_Z6VEC register.
The BAM reads the status of the BOOTCFG bit from the reset status register (SIU_RSR) and the
appropriate boot sequence is started (see
shows the encoding of the BOOTCFG bit in the SIU_RSR, with the value stored in the
Censorship word in the shadow row of internal flash memory. The table also shows whether the internal
flash memory is enabled or disabled, whether the Nexus port is enabled or disabled, and whether the
password downloaded in serial-boot mode is compared with a fixed public password or compared to a user
programmable flash password.
Table 9-2. Boot Modes
Boot Mode Name
BOOTCFG
Censorship
Control
0x00FF_FDE0
Serial Boot
Control
0x00FF_FDE2
Internal
Flash
State
Nexus State
Serial
Password
Internal—Censored
0
Any other value
Don't care
Enabled
Disabled
Flash
Internal—Public
0x55AA
Enabled
Enabled
Public
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...
Страница 1257: ...Nexus Development Interface NDI PXN20 Microcontroller Reference Manual Rev 1 Freescale Semiconductor 36 107...
Страница 1258: ...Nexus Development Interface NDI PXN20 Microcontroller Reference Manual Rev 1 36 108 Freescale Semiconductor...
Страница 1376: ...Memory Map PXN20 Microcontroller Reference Manual Rev 1 A 118 Freescale Semiconductor...