CDR3 Flash (UC3F) EEPROM
MPC561/MPC563 Reference Manual, Rev. 1.2
21-32
Freescale Semiconductor
21.3.11.2 Setting Censor
The set operation changes the state in an NVM CAM cell from a 0 to a 1. This set operation can be done
without changing the contents of the UC3F array. The required sequence to set one or both of the bits in
CENSOR[0:1] follows.
1. Write CSC = 1, PE = 0 and SES = 1 in the UC3FCTL register
2. Write a 1 to the CENSOR bit(s) to be set
3. Write EHV = 1 in the UC3FCTL register
4. Read the UC3FCTL register until HVS = 0
5. Read the UC3FCTL register. Confirm PEGOOD = 1
6. Write EHV = 0 in the UC3FCTL register
7. Write SES = 0 and CSC = 0
21.3.11.3 Clearing Censor
The clear operation changes the state of the CENSOR[0:1] bits from a 1 to a 0 by erasing the CAM cells.
This clear operation can be done only while erasing the entire UC3F array and shadow information. The
required sequence to clear CENSOR follows.
Clear CENSOR[0:1]
1. Write PROTECT[0:7] = 0x00 to enable the entire array for erase. If SBEN[M] = 1, then
SBPROTECT[M] must also be cleared to 0.
2. Write BLOCK[0:7] = 0xFF, CSC = 1, PE = 1 and SES = 1 in the UC3FCTL register. If SBEN[M]
= 1, then SBBLOCK[M] must also be set to 1.
3. Do an erase interlock write.
On the UC3F module, the erase interlock write can be performed in one of two ways, depending
on the value of the UC3FCFIG bit 15, IWS.
If IWS = 0, a valid erase interlock write is a write to any valid array location. This is subject to any
censorship conditions that might apply.
If IWS = 1, a valid erase interlock write can be a write to any valid array location or a write to the
UC3FCMCR register.
When the IWS = 1, the CENSOR[0:1] bits can always be cleared in the UC3F flash EEPROM
status states #3, #4 and #5 from
.
The erase interlock write is only valid if all blocks of the array are selected for erase and not
protected. BLOCK[0:7] and SBBLOCK[0:1] set to 1, as well as PROTECT[0:7] and
SBPROTECT[0:1] set to 0, are required for a valid erase interlock write during the clear censor
operation.
4. Write EHV = 1 in the UC3FCTL register.
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...