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TMP86PM29BUG
6. Watchdog Timer (WDT)
The watchdog timer is a fail-safe system to detect rapidly the CPU malfunctions such as endless loops due to spu-
rious noises or the deadlock conditions, and return the CPU to a system recovery routine.
The watchdog timer signal for detecting malfunctions can be programmed only once as “reset request” or “inter-
rupt request”. Upon the reset release, this signal is initialized to “reset request”.
When the watchdog timer is not used to detect malfunctions, it can be used as the timer to provide a periodic inter-
rupt.
Note: Care must be taken in system design since the watchdog timer functions are not be operated completely due to
effect of disturbing noise.
6.1
Watchdog Timer Configuration
Figure 6-1 Watchdog Timer Configuration
0034
H
Overflow
WDT output
Internal reset
Binary counters
WDTOUT
Writing
clear code
Writing
disable code
WDTEN
WDTT
2
0035
H
Watchdog timer control registers
WDTCR1
WDTCR2
INTWDT
interrupt
request
Interrupt request
Reset
request
Reset release
Clock
Clear
1
2
Controller
Q
S
R
S
R
Q
Selector
fc/2
23
or fs/2
15
fc/2
21
or fs/2
13
fc/2
19
or fs/2
11
fc/2
17
or fs/2
9
Summary of Contents for TLCS-870/C Series
Page 1: ...8 Bit Microcontroller TLCS 870 C Series TMP86PM29BUG ...
Page 6: ...TMP86PM29BUG ...
Page 7: ...Revision History Date Revision 2007 10 11 1 First Release 2008 8 29 2 Contents Revised ...
Page 9: ......
Page 15: ...vi ...
Page 19: ...Page 4 1 3 Block Diagram TMP86PM29BUG 1 3 Block Diagram Figure 1 2 Block Diagram ...
Page 23: ...Page 8 1 4 Pin Names and Functions TMP86PM29BUG ...
Page 48: ...Page 33 TMP86PM29BUG ...
Page 49: ...Page 34 2 Operational Description 2 3 Reset Circuit TMP86PM29BUG ...
Page 61: ...Page 46 3 Interrupt Control Circuit 3 8 External Interrupts TMP86PM29BUG ...
Page 81: ...Page 66 6 Watchdog Timer WDT 6 3 Address Trap TMP86PM29BUG ...
Page 135: ...Page 120 10 8 Bit TimerCounter TC5 TC6 10 1 Configuration TMP86PM29BUG ...
Page 145: ...Page 130 11 Asynchronous Serial interface UART 11 9 Status Flag TMP86PM29BUG ...
Page 165: ...Page 150 13 10 bit AD Converter ADC 13 6 Precautions about AD Converter TMP86PM29BUG ...
Page 183: ...Page 168 15 LCD Driver 15 4 Control Method of LCD Driver TMP86PM29BUG ...
Page 201: ...Page 186 18 Electrical Characteristics 18 9 Handling Precaution TMP86PM29BUG ...
Page 203: ...Page 188 19 Package Dimensions TMP86PM29BUG ...
Page 205: ......