276
CHAPTER 15 WATCH TIMER
15.5
Explanation of Operation of Watch Timer
The watch timer operates as an interval timer or an oscillation stabilization wait time
timer of subclock. It also supplies an operation clock to the watchdog timer.
■
Watch Timer Counter
The watch timer counter continues incrementing in synchronization with the subclock (SCLK) while the
subclock (SCLK) is operating.
●
Clearing watch timer counter
The watch timer counter is cleared to "0000
H
" when:
•
A power-on reset occurs.
•
The mode transits to the stop mode.
•
The watch timer clear bit (WTR) in the watch timer control register (WTC) is set to "0".
Note:
When the watch timer counter is cleared, the interrupts of the watchdog timer and interval timer that use
the output of the watch timer counter are affected.
To clear the watch timer by writing zero to the watch timer clear bit (WTR) in the watch timer control
register (WTC), set the overflow interrupt enable bit (WTIE) in the WTC register to "0" and set the watch
timer to interrupt inhibited state. Before permitting an interrupt, clear the interrupt request issued by
writing zero to the overflow flag bit (WTOF) in the WTC register.
■
Interval Timer Function
The watch timer can be used as an interval timer by generating an interrupt at each interval time.
●
Settings when using watch timer as interval timer
Operating the watch timer as an interval timer requires the settings shown in Figure 15.5-1 .
Figure 15.5-1 Setting of Watch Timer
•
When the value set by the interval time select bits (WTC1, WTC0) in the watch timer control register
(WTC) is reached, the overflow flag bit in the WTC register is set to "1" (WTC:WTOF = 1).
•
When the overflow flag bit is set (WTC:WTOF = 1) with the overflow interrupt of the watch timer
counter enabled (WTC:WTIE = 1), an interrupt request is generated.
•
The overflow flag bit (WTC:WTOF) is set when the interval time is reached at the starting point of the
timing at which the watch timer is finally cleared.
WTC
6
5
4
3
2
1
WTOF WTR
WTC1
WTC2
SCE WTIE
WTC0
WDCS
bit7
bit0
: Used bit
: Unused bit
Содержание F2MCTM-16LX
Страница 2: ......
Страница 3: ...FUJITSU LIMITED F2MCTM 16LX 16 BIT MICROCONTROLLER MB90360 Series HARDWARE MANUAL ...
Страница 4: ......
Страница 42: ...26 CHAPTER 1 OVERVIEW ...
Страница 66: ...50 CHAPTER 2 CPU MOV ILM imm8 The instruction is executed normally but the prefix affects the next instruction ...
Страница 70: ...54 CHAPTER 2 CPU ...
Страница 134: ...118 CHAPTER 6 CLOCK SUPERVISOR ...
Страница 176: ...160 CHAPTER 8 LOW POWER CONSUMPTION MODE ...
Страница 194: ...178 CHAPTER 10 I O PORTS ...
Страница 252: ...236 CHAPTER 13 16 Bit I O TIMER ...
Страница 282: ...266 CHAPTER 14 16 BIT RELOAD TIMER ...
Страница 295: ...279 CHAPTER 15 WATCH TIMER ORG 00FFDCH Reset vector set DSL START DB 00H Set to single chip mode VECT ENDS END START ...
Страница 296: ...280 CHAPTER 15 WATCH TIMER ...
Страница 386: ...370 CHAPTER 18 8 10 BIT A D CONVERTER ...
Страница 426: ...410 CHAPTER 20 LIN UART Figure 20 5 2 ORE Flag Set Timing RDRF ORE Reception data ...
Страница 540: ...524 CHAPTER 22 ADDRESS MATCH DETECTION FUNCTION ...
Страница 568: ...552 CHAPTER 24 512K BIT FLASH MEMORY ...
Страница 633: ...617 APPENDIX B Instructions Table B 9 3 Bit Operation Instruction Map first byte 6CH ...
Страница 634: ...618 APPENDIX Table B 9 4 Character String Operation Instruction Map first byte 6EH ...
Страница 635: ...619 APPENDIX B Instructions Table B 9 5 2 byte Instruction Map first byte 6FH MUL MULW DIVU A A A ...
Страница 637: ...621 APPENDIX B Instructions Table B 9 7 ea Instruction 2 first byte 71H ...
Страница 638: ...622 APPENDIX Table B 9 8 ea Instruction 3 first byte 72H ...
Страница 639: ...623 APPENDIX B Instructions Table B 9 9 ea Instruction 4 first byte 73H ...
Страница 640: ...624 APPENDIX Table B 9 10 ea Instruction 5 first byte 74H ...
Страница 641: ...625 APPENDIX B Instructions Table B 9 11 ea Instruction 6 first byte 75H ...
Страница 642: ...626 APPENDIX Table B 9 12 ea Instruction 7 first byte 76H ...
Страница 643: ...627 APPENDIX B Instructions Table B 9 13 ea Instruction 8 first byte 77H ...
Страница 644: ...628 APPENDIX Table B 9 14 ea Instruction 9 first byte 78H ...
Страница 645: ...629 APPENDIX B Instructions Table B 9 15 MOVEA RWi ea Instruction first byte 79H ...
Страница 646: ...630 APPENDIX Table B 9 16 MOV Ri ea Instruction first byte 7AH ...
Страница 647: ...631 APPENDIX B Instructions Table B 9 17 MOVW RWi ea Instruction first byte 7BH ...
Страница 648: ...632 APPENDIX Table B 9 18 MOV Ri ea Instruction first byte 7CH ...
Страница 649: ...633 APPENDIX B Instructions Table B 9 19 MOVW ea Rwi Instruction first byte 7DH ...
Страница 650: ...634 APPENDIX Table B 9 20 XCH Ri ea Instruction first byte 7EH ...
Страница 651: ...635 APPENDIX B Instructions Table B 9 21 XCHW RWi ea Instruction first byte 7FH ...
Страница 664: ...648 APPENDIX ...
Страница 665: ...649 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
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