Freescale Semiconductor MPC5604B - Chapter 10 UART: Universal Asynchronous Receiver Transmitter; 1. Introduction to UART; 2. Module Presentation

MPC5604B/C Microcontroller Reference Manual, Rev. 8
Freescale Semiconductor 71
Figure 5-5. Censorship control in serial boot mode
5.2 Boot Assist Module (BAM)
The BAM consits of a block of ROM at address 0xFFFF_C000 containing VLE firmware. The BAM
provides 2 main functions:
• Manages the serial download (FlexCAN or LINFlex protocols supported) including support for a
serial password if censorship is enabled
• Places the microcontroller into static mode if flash memory boot mode is selected and a valid
BOOT_ID is not located in one of the boot sectors by the SSCM
5.2.1 BAM software flow
Figure 5-6 illustrates the BAM logic flow.
FAB = 1
(Serial boot mode)
NVSCC0 !=
NVSCC1
?
True
Censored with no
password access
(Locked out)
Serial password details:
Enter public password
0xFEEDFACE_CAFEBEEF
False
False
False
Both
SC and CW !=
0x55AA
SC != 0x55AA
?
?
True
Censored with no
password access
(Locked out)
True
Note:
CW = 0x55AA
False
CW != 0x55AA
?
True
Note:
SC = 0x55AA
Public password,
Uncensored
Flash
(private) password,
Censored
Flash
(private) password,
Uncensored
Enter password as
{NVPWD1, NVPWD0}
example –
0x89ABCDEF_01234567
Enter password as
{NVPWD0, NVPWD1}
example –
0x01234567_89ABCDEF