Freescale Semiconductor MPC5604B - Page 80

MPC5604B/C Microcontroller Reference Manual, Rev. 8
Freescale Semiconductor 69
The flow charts in Figure 5-4 and Figure 5-5 provide a way to quickly check what will happen with
different configurations of the NVSCC0,1 registers as well as detailing the correct way to enter the serial
password. In the password examples, assume the 64-bit password has been programmed into the shadow
flash memory in the order {NVPWD0, NWPWD1} and has a value of 0x01234567_89ABCDEF.
Table 5-4. Censorship configuration and truth table
Boot configuration Serial
censorship
control word
(NVSCCn[SC]
)
Censorship
control word
(NVSCCn[CW])
Internal
flash
memory
state
Nexus
state
Serial
password
JTAG
passwordFAB pin
state
Control options
0 (flash
memory
boot)
Uncensored 0xXXXX AND
NVSCC0 ==
NVSCC1
0x55AA AND
NVSCC0 ==
NVSCC1
Enabled Enabled
N/A
Private flash
memory password
and censored
0x55AA AND
NVSCC0 ==
NVSCC1
!0x55AA AND
NVSCC0 ==
NVSCC1
Enabled Enabled
with
password
NVPWD1,0
(SSCM
reads flash
memory
1
)
1
When the SSCM reads the passwords from flash memory, the NVPWD0 and NVPWD1 password order is swapped, so
you have to submit the 64-bit password as {NVPWD1, NVPWD0}.
Censored with no
password access
(lockout)
!0x55AA !0X55AA Enabled Disabled N/A
OR
NVSCC0 != NVSCC1
1 (serial
boot)
Private flash
memory password
and uncensored
0x55AA AND
NVSCC0 == NVSCC1
Enabled Enabled NVPWD0,1
(BAM reads
flash
memory
1
)
Private flash
memory password
and censored
0x55AA AND
NVSCC0 ==
NVSCC1
!0x55AA AND
NVSCC0 ==
NVSCC1
Enabled Disabled NVPWD1,0
(SSCM
reads flash
memory
1
)
Public password
and uncensored
!0x55AA AND
NVSCC0 !=
NVSCC1
0X55AA AND
NVSCC0 !=
NVSCC1
Enabled Enabled Public
(0xFEED_F
ACE_CAFE
_BEEF)
Public password
and censored
(lockout)
!0x55AA Disabled Disabled Public
(0xFEED_F
ACE_CAFE
_BEEF)
OR NVSCC0 != NVSCC1
= Microcontroller permanently locked out
= Not applicable