LM3S5791-IQC80-C5T Datasheet, PDF (578/1332 Pages) Texas Instruments – Stellaris LM3S5791 Microcontroller

Watchdog Timers
NRND: Not recommended for new designs.
Register 3: Watchdog Control (WDTCTL), offset 0x008
This register is the watchdog control register. The watchdog timer can be configured to generate a
reset signal (on second time-out) or an interrupt on time-out.
When the watchdog interrupt has been enabled by setting the INTEN bit, all subsequent writes to
the INTEN bit are ignored. The only mechanism that can re-enable writes to this bit is a hardware
reset.
Important: Because the Watchdog Timer 1 module has an independent clocking domain, its
registers must be written with a timing gap between accesses. Software must guarantee
that this delay is inserted between back-to-back writes to WDT1 registers or between
a write followed by a read to the registers. The timing for back-to-back reads from the
WDT1 module has no restrictions. The WRC bit in the Watchdog Control (WDTCTL)
register for WDT1 indicates that the required timing gap has elapsed. This bit is cleared
on a write operation and set once the write completes, indicating to software that another
write or read may be started safely. Software should poll WDTCTL for WRC=1 prior to
accessing another register. Note that WDT0 does not have this restriction as it runs off
the system clock and therefore does not have a WRC bit.
Watchdog Control (WDTCTL)
WDT0 base: 0x4000.0000
WDT1 base: 0x4000.1000
Offset 0x008
Type R/W, reset 0x0000.0000 (WDT0) and 0x8000.0000 (WDT1)
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
WRC
reserved
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
reserved
RESEN INTEN
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
R/W
R/W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
31
30:2
Name
WRC
reserved
Type
RO
RO
Reset Description
1
Write Complete
The WRC values are defined as follows:
Value Description
0 A write access to one of the WDT1 registers is in progress.
1 A write access is not in progress, and WDT1 registers can be
read or written.
Note: This bit is reserved for WDT0 and has a reset value of 0.
0x000.000 Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
578
October 05, 2012
Texas Instruments-Production Data