Qorivva MPC5xxx/SPC5xx Debugger and NEXUS Trace
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©1989-2021 Lauterbach GmbH
Programming Serial Boot Password and Censorship Word
After enabling shadow row programming as described above, the serial boot password can be programmed.
The censorship word has an extra protection. By default, the debugger will force that the censorship word
gets programmed to 0x55AA55AAFFFFFFFF (for C90LC-Flash: 0x55AA55AA55AA55AA). In order to
program the censorship word, use the following sequence:
The next sequence shows how to disable censorship:
Newer processors (MPC56XX, SPC56X and later) have a feature to inhibit censorship via JTAG (using the
serial password). See
for details.
;prepare flash programming and enable shadow row
DO ~~/demo/powerpc/flash/mpc5xxx.cmm PREPAREONLY
FLASH.CHANGETYPE <shadow_row_base>++<size> TARGET
;programming sequence to
enable censored mode
FLASH.AUTO <shadow_row_base>++<size>
/CENSORSHIP
Data.Set <censorship_address> %QUAD 0x55AA
1234
FFFFFFFF ;for
C90FL/H7F
Data.Set <censorship_address> %QUAD 0x55AA
1234
55AA
1234
;for
C90LC
Data.Set <password_address> %QUAD 0xFEEDFACECAFEBEEF ;set password
FLASH.AUTO off
;prepare flash programming and enable shadow row
DO ~~/demo/powerpc/flash/mpc5xxx.cmm PREPAREONLY
FLASH.CHANGETYPE <shadow_row_base>++<size> TARGET
;programming sequence to
uncensor
device
FLASH.AUTO <shadow_row_base>++<size>
/CENSORSHIP
Data.Set <censorship_address> %QUAD 0x55AA55AAFFFFFFFF ;for
C90FL/H7F
Data.Set <censorship_address> %QUAD 0x55AA55AA55AA55AA ;for
C90LC
Data.Set <password_address> %QUAD 0xFEEDFACECAFEBEEF ;default password
FLASH.AUTO off
NOTE:
The censorship word must have at least one bit set to 0 and one set to 1, in
each half word (16 bit block).
A valid password must have at least one bit set to 0 and one set to 1, in each
half word (16 bit block). The password restriction only applies to 64-bit
passwords. Processors with 256-bit passwords do not have that restriction.
