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5. Watchdog Timer (WDT)
5.3 Functions
TMP89FM42
RA000
5.3.6
Reading the 8-bit up counter
The counter value of the 8-bit up counter can be read by reading WDCNT.
The stoppage of the 8-bit up counter can be detected by reading WDCNT at random times and comparing the
value to the last read value.
5.3.7
Reading the watchdog timer status
The watchdog timer status can be read at WDST.
WDST<WDTST> is set to "1" when the watchdog timer operation is enabled, and it is cleared to "0" when
the watchdog timer operation is disabled.
WDST<WINTST2> is set to "1" when a watchdog timer interrupt request signal occurs due to the overflow
of the 8-bit up counter.
WDST<WINTST1> is set to "1" when a watchdog timer interrupt request signal occurs due to the operation
for releasing the 8-bit up counter outside the clear time.
You can know which factor has caused a watchdog timer interrupt request signal by reading
WDST<WINTST2> and WDST<WINTST1> in the watchdog timer interrupt service routine.
WDST<WINTST2> and WDST<WINTST1> are cleared to "0" when WDST is read. If WDST is read at the
same time as the condition for turning WDST<WINTST2> or WDST<WINTST1> to "1" is satisfied,
WDST<WINTST2> or WDST<WINTST1> is set to "1", rather than being cleared.
Figure 5-4 Changes in the Watchdog Timer Status
8-bit up counter value
When WDCTR<WDTW> is 10
Writing of 4EH (clear code)
WDST<WINTST1>
Watchdog timer interrupt request signal
Interrupt request signal generated by clearing
the 8-bit up counter outside the clear time
Interrupt request signal generated by the
overflow of the 8-bit up counter
00H
01H
3FH 40H
01H
7FH 80H
BFH C0H
FFH 00H
FFH
Clear time
Outside the clear time
Reading of WDST
WDST<WINTST2>
Summary of Contents for TLCS-870/C1 Series
Page 1: ...8 Bit Microcontroller TLCS 870 C1 Series TMP89FM42 查询TMP89FM42供应商 捷多邦 专业PCB打样工厂 24小时加急出货 ...
Page 3: ...Revision History Date Revision 2007 10 25 1 First Release 2007 11 3 2 Contents Revised ...
Page 4: ......
Page 14: ......
Page 18: ...1 3 Block Diagram TMP89FM42 1 3 Block Diagram Figure 1 2 Block Diagram ...
Page 22: ...1 4 Pin Names and Functions TMP89FM42 ...
Page 60: ...2 CPU Core 2 5 Revision History TMP89FM42 ...
Page 76: ...3 Interrupt Control Circuit 3 8 Revision History TMP89FM42 ...
Page 86: ...4 External Interrupt control circuit 4 3 Function TMP89FM42 ...
Page 102: ...7 Voltage Detection Circuit 7 5 Revision History TMP89FM42 ...
Page 126: ...8 I O Ports 8 3 I O Port Registers TMP89FM42 Note 2 i 0 to 1 ...
Page 136: ...8 I O Ports 8 5 Revision History TMP89FM42 ...
Page 142: ...9 Special Function Registers 9 3 SFR3 0x0E40 to 0x0EFF TMP89FM42 ...
Page 146: ...10 Low Power Consumption Function for Peripherals TMP89FM42 ...
Page 149: ...TMP89FM42 11 3 Revision History Rev Description RA001 Deleted SLEEP2 description ...
Page 150: ...11 Divider Output DVO 11 3 Revision History TMP89FM42 ...
Page 220: ...15 Real Time Clock RTC 15 4 Real Time Clock Operation TMP89FM42 ...
Page 250: ...16 Asynchronous Serial Interface UART 16 15 Revision History TMP89FM42 ...
Page 302: ...18 Serial Bus Interface SBI 18 7 Revision History TMP89FM42 ...
Page 338: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 ...
Page 384: ...22 Serial PROM Mode 22 15 Revision History TMP89FM42 ...
Page 388: ...24 Input Output Circuit 24 1 Control Pins TMP89FM42 ...
Page 404: ...25 Electrical Characteristics 25 11 Revision History TMP89FM42 ...
Page 406: ...26 Package Dimensions TMP89FM42 ...
Page 408: ......