Datasheet

274
32142D–06/2013
ATUC64/128/256L3/4U
14.6.7 Unlock Register
Name:
UNLOCK
Access Type: Write-only
Offset: 0x0018
Reset Value: 0x00000000
To unlock a write protected register, first write to the UNLOCK register with the address of the register to unlock in the ADDR
field and 0xAA in the KEY field. Then, in the next PB access write to the register specified in the ADDR field.
The LOCK is by default off. To turn on the LOCK, first write 0xAA to the KEY field and UNLOCK address offset to the ADDR field
in the UNLOCK register, followed by writing 0x5A5A5A5A to the UNLOCK register. To turn off the LOCK, first write 0xAA to the
KEY field and UNLOCK address offset to the ADDR field in the UNLOCK register, followed by writing 0xA5AA5A55 to the
UNLOCK register.
• KEY: Unlock Key
Write this bit field to 0xAA to enable unlock.
• ADDR: Unlock Address
Write the address offset of the register to unlock to this field.
31 30 29 28 27 26 25 24
KEY
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
------ ADDR[9:8]
76543210
ADDR[7:0]