DRAFT
DRAFT DRAFT DR
DRAFT DRAFT DRAFT
D
RAF
DRAFT DRAFT DRA
FT D
RAFT DR
AFT D
DRA
FT DRAFT DRAFT
D
RAFT
DRAFT
D
RAFT
DRA
UM10601
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Preliminary user manual
Rev. 1.0 — 7 November 2012
154 of 313
NXP Semiconductors
UM10601
Chapter 12: LPC800 Windowed Watchdog Timer (WWDT)
12.7 Functional description
The following figures illustrate several aspects of Watchdog Timer operation.
Table 148. Watchdog Timer Window register (WINDOW - 0x4000 4018) bit description
Bit
Symbol
Description
Reset
Value
23:0
WINDOW Watchdog window value.
0xFF FFFF
31:24 -
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
NA
Fig 17. Early watchdog feed with windowed mode enabled
$
:'&/.
:DWFKGRJ
&RXQWHU
(DUO\)HHG
(YHQW
:DWFKGRJ
5HVHW
&RQGLWLRQV
:,1'2:
[
:$51,17
[))
7&
[
Fig 18. Correct watchdog feed with windowed mode enabled
&RUUHFW)HHG
(YHQW
))
:'&/.
:DWFKGRJ
&RXQWHU
:DWFKGRJ
5HVHW
)&
)'
))(
)))
)(
))' ))&
&RQGLWLRQV
:':,1'2: [
:':$51,17 [))
:'7&
[
Fig 19. Watchdog warning interrupt
:DWFKGRJ
,QWHUUXSW
:'&/.
:DWFKGRJ
&RXQWHU
)(
))
)'
)%
)&
)$ )
&RQGLWLRQV
:,1'2:
[
:$51,17
[))
7&
[