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CHAPTER 3 CPU
3.7.6
Oscillation Stabilization Wait Time
At power on or return from the stop mode when the oscillation clock is stopped, a time
until the oscillation clock stabilizes (oscillation stabilization wait time) is required after
starting an oscillation.The oscillation stabilization wait time is also required for
switching the clock mode from main clock mode to PLL clock or subclock mode and
from subclock mode to main clock or PLL clock mode.
■
Operation During Oscillation Stabilization Wait Time
Ceramic and crystal oscillators require some tens of milliseconds to reach a stable oscillation frequency
after starting oscillation.Therefore when, immediately after an oscillation starts, once the CPU operation is
disabled and then an oscillation stabilizes after the elapse of oscillation stabilization wait time, the machine
clock is supplied to the CPU.
The oscillation stabilization wait time varies with the type of oscillator (ceramic, crystal, etc.).It is
necessary to select a oscillation stabilization wait time appropriate to an oscillator to be used.The
oscillation stabilization wait time can be selected using the clock select register (CKSCR).
When the clock mode changes from main clock mode to PLL clock or subclock mode or from subclock
mode to main clock or PLL clock mode, the CPU runs to the previous clock during the oscillation
stabilization wait time. When the oscillation stabilization wait time has elapsed, the CPU changes to the
specified clock mode.
Figure 3.7-7 shows the oscillating operation immediately after it starts.
Figure 3.7-7 Operation after Oscillation Stabilization Wait Time
Note:
There is no sub-clock in MB90F897S.
Oscillation
stabilization time
Oscillating start
Oscillating stabilization
X1
The oscillation time
for the oscillator
Start the normal operation or
change to PLL clock/subclock
Summary of Contents for F2MC-16LX Series
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Page 3: ...FUJITSU LIMITED F2MC 16LX 16 bit Microcontroller MB90895 series Hardware Manual ...
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Page 8: ...iv ...
Page 10: ...vi ...
Page 36: ...18 CHAPTER 2 HANDLING DEVICES ...
Page 176: ...158 CHAPTER 3 CPU ...
Page 224: ...206 CHAPTER 5 Timebase timer ...
Page 294: ...276 CHAPTER 8 16 bit reload timer ...
Page 366: ...348 CHAPTER 12 DTP external interrupt ...
Page 398: ...380 CHAPTER 13 8 10 bit A D converter ...
Page 446: ...428 CHAPTER 14 UART0 ...
Page 588: ...570 CHAPTER 17 Address Match Detecting Function ...
Page 626: ...608 CHAPTER 19 512 KBIT FLASH MEMORY ...
Page 676: ...658 APPENDIX Table A 9 3 Bit Operation Instruction Map first byte 6CH ...
Page 678: ...660 APPENDIX Table A 9 5 2 byte Instruction Map first byte 6FH MUL MULW DIVU A A A ...
Page 680: ...662 APPENDIX Table A 9 7 ea Instruction 2 first byte 71H ...
Page 681: ...663 APPENDIX A Instructions Table A 9 8 ea Instruction 3 first byte 72H ...
Page 682: ...664 APPENDIX Table A 9 9 ea Instruction 4 first byte 73H ...
Page 683: ...665 APPENDIX A Instructions Table A 9 10 ea Instruction 5 first byte 74H ...
Page 684: ...666 APPENDIX Table A 9 11 ea Instruction 6 first byte 75H ...
Page 685: ...667 APPENDIX A Instructions Table A 9 12 ea Instruction 7 first byte 76H ...
Page 686: ...668 APPENDIX Table A 9 13 ea Instruction 8 first byte 77H ...
Page 687: ...669 APPENDIX A Instructions Table A 9 14 ea Instruction 9 first byte 78H ...
Page 688: ...670 APPENDIX Table A 9 15 MOVEA RWi ea Instruction first byte 79H ...
Page 689: ...671 APPENDIX A Instructions Table A 9 16 MOV Ri ea Instruction first byte 7AH ...
Page 690: ...672 APPENDIX Table A 9 17 MOVW RWi ea Instruction first byte 7BH ...
Page 691: ...673 APPENDIX A Instructions Table A 9 18 MOV ea Ri Instruction first byte 7CH ...
Page 692: ...674 APPENDIX Table A 9 19 MOVW ea Rwi Instruction first byte 7DH ...
Page 693: ...675 APPENDIX A Instructions Table A 9 20 XCH Ri ea Instruction first byte 7EH ...
Page 694: ...676 APPENDIX Table A 9 21 XCHW RWi ea Instruction first byte 7FH ...
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