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 Page 16-10, 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. Table 16-3 lists the required
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.