MPC555
/
MPC556
CDR MoneT FLASH EEPROM
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
19-33
The only way CENSOR[0:1] can be changed is by setting or clearing the FLASH NVM
fuses. In the information censorship state, CENSOR[0:1] must be cleared to the
cleared censorship state before CENSOR[0:1] can be put into the no-censorship state.
CAUTION
Clearing the CENSOR[0:1] bits causes the entire CMF array to be
erased.
19.8.4 Setting and Clearing Censor
The value of each bit in CENSOR[0:1] is determined by the state of two NVM bits in a
special NVM fuse as shown in
. These two NVM bits are not part of the
main flash array. The NVM fuse is not writable but instead may be set or cleared. The
two NVM bits in the NVM fuse are programmed and erased simultaneously to change
Table 19-16 CMF EEPROM Devices Modes and Censorship Status
Device Mode
Censored
Uncensored
ACCESS
0
1
0
1
FIC
0
1
0
1
0
1
0
1
CENSOR[0:1]
00
01
or
10
11
00,
01
or
10
11
00, 01, 10 or 11
CMF EEPROM Status
#1
#2
#3
#4
#5
#6
#7
#8
#9
#10
#11
#1
CMF array can not be accessed. ACCESS can not be changed. FIC can be set. CEN-
SOR[0:1] can be set. CENSOR[0:1] can not be cleared.
#2
CMF array can be accessed. ACCESS can not be changed. FIC can be set. CEN-
SOR[0:1] can be set. CENSOR[0:1] can be cleared.
#3
CMF array can not be accessed. ACCESS can not be changed. FIC can be set. CEN-
SOR[0:1] can not be cleared.
#4
CMF array can not be accessed. ACCESS can not be changed. FIC can not be
changed. CENSOR[0:1] can be set. CENSOR[0:1] can not be cleared.
#5
CMF array can not be accessed. ACCESS can not be changed. FIC can not be
changed. CENSOR[0:1] can not be cleared.
#6
CMF array can be accessed. ACCESS can be cleared. FIC can be set. CENSOR[0:1]
can be changed.
#7
CMF array can be accessed. ACCESS can be cleared. FIC can not be changed. CEN-
SOR[0:1] can be changed.
#8
CMF array can be accessed. ACCESS can be changed. FIC can be set. CEN-
SOR[0:1] can be changed.
#9
CMF array can be accessed. ACCESS can be changed. FIC can not be changed.
CENSOR[0:1] can be changed.
#10
CMF array can be accessed. ACCESS can be changed. FIC can be set. CEN-
SOR[0:1] can be changed.
#11
CMF array can be accessed. ACCESS can be changed. FIC can not be changed.
CENSOR[0:1] can be changed.
= Indicates that the CMF array can not be accessed.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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