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TC1796
System Units (Vol. 1 of 2)
Watchdog Timer
User’s Manual
16-11
V2.0, 2007-07
WDT, V2.0
16.4.4
Modify Access to WDT_CON0
If WDT_CON0 is successfully unlocked as described on
, the following write
access to WDT_CON0 can modify it. However, this access must also meet certain
requirements in order to be accepted and regarded as valid.
bit patterns. If the access does not follow these rules, a Watchdog Access Error condition
is detected, bit WDTAE is set, and the Prewarning Mode is entered.
After the Modify Access has completed, WDT_CON0.WDTLCK is set to 1 again by
hardware, automatically re-locking WDT_CON0. Before the register can be modified
again, a Valid Password Access must be executed again.
Table 16-3
Modify Access Bit Pattern Requirements
Bit Position Value
0
User-definable; desired value for the ENDINIT bit,
WDT_CON0.ENDINIT.
1
Fixed; must be written with 1.
2
Fixed; must be written with 0.
3
Fixed; must be written with 0.
[7:4]
Fixed; must be written with 1111
B
.
[15:8]
User-definable; desired value of user-definable password field,
WDT_CON0.WDTPW.
[31:16]
User-definable; desired value of user-definable reload value,
WDT_CON0.WDTREL.