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Chapter 18 Timebase Counter
8.Caution
8. Caution
• Clock source
If the clock selected as the clock source is not stable, an oscillation stabilization wait time is required.
• Oscillation stabilization wait time
The wait time set in the oscillation stabilization time selection bits (STCR.OS[1:0]) is not initialized by any
reset except a reset triggered by the external INITX pin input, the RC based watchdog or the Clock
Supervisor. For other resets including settings initialization resets (timebase counter based watchdog reset)
and operation initialization resets (RST), the wait time set prior to the reset is used.
• Watchdog reset (Timebase Counter based watchdog)
Although an oscillation stabilization wait time is not required if a watchdog reset occurs while the main clock
is running (main or sub), a wait time is generated automatically. In this case, the oscillation stabilization wait
time (STCR.OS[1:0]) is not initialized.
• “L” level input to INIT pin
As the oscillation stabilization wait time is initialized to its minimum value when an initialization is triggered
by an INIT pin input, the wait time in this case is too short. Ensure the INIT pin input width is long enough to
provide the oscillation stabilization wait time.
In the following three cases, maintain the INIT pin input at the “L” level for long enough to provide the
oscillation stabilization wait time required by the oscillation circuit.
• INIT pin input after turning on the power
• INIT pin input after oscillation halted in stop mode
• INIT pin input when subclock selected as the clock source and main clock oscillation halted
(Accordingly, to stabilize the oscillation of both the main and subclocks, input an “L” level to the INIT pin for
long enough to provide a sufficient oscillation stabilization time for both the main and subclocks.)
• Main PLL lock wait
If enabling the main PLL from the halted state after program execution starts, the main PLL must not be
used until after sufficient time has elapsed for the main PLL to lock.
Similarly, when changing the multiplier setting for the main PLL when the PLL is running, the new main PLL
clock must not be used until sufficient time has elapsed for the main PLL to lock.
Using the timebase timer interrupt to generate the main PLL lock wait time is recommended.
• Cases when oscillation stabilization wait is not required
Although no oscillation stabilization wait is required when recovering via an interrupt from main stop or sub
stop mode when the main clock oscillation has not been halted, the oscillation stabilization wait is generated
automatically. Setting the wait time to its minimum value prior to entering stop mode is recommended.
Summary of Contents for FR Family FR60 Lite
Page 2: ...FUJITSU LIMITED ...
Page 3: ...FR60 32 BIT MICROCONTROLLER MB91460 Series User s Manual ...
Page 15: ...xi ...
Page 16: ...xii ...
Page 38: ...22 Chapter 2 MB91460 Rev A Rev B Overview 4 Block Diagram ...
Page 128: ...112 Chapter 4 CPU Architecture 9 Addressing ...
Page 153: ...137 Chapter 8 Device State Transition 3 State Transition Diagram ...
Page 154: ...138 Chapter 8 Device State Transition 3 State Transition Diagram ...
Page 169: ...153 Chapter 9 Reset 10 Caution ...
Page 170: ...154 Chapter 9 Reset 10 Caution ...
Page 180: ...164 Chapter 10 Standby 7 Q A ...
Page 182: ...166 Chapter 10 Standby 8 Caution ...
Page 199: ...183 Chapter 12 Instruction Cache 2 Main body structure Figure 2 3 I Cache Address Map ...
Page 200: ...184 Chapter 12 Instruction Cache 2 Main body structure Figure 2 4 I Cacheable Area ...
Page 222: ...206 Chapter 13 Clock Control 8 Caution ...
Page 232: ...216 Chapter 14 PLL Interface 7 Caution ...
Page 236: ...220 Chapter 15 CAN Clock Prescaler 3 Registers ...
Page 288: ...272 Chapter 19 Timebase Timer 8 Caution ...
Page 314: ...298 Chapter 22 Main Oscillation Stabilisation Timer 8 Caution ...
Page 326: ...310 Chapter 23 Sub Oscillation Stabilisation Timer 8 Caution ...
Page 348: ...332 Chapter 25 External Interrupt 8 Caution ...
Page 398: ...382 Chapter 26 DMA Controller 6 DMA External Interface ...
Page 402: ...386 Chapter 27 Delayed Interrupt 8 Caution ...
Page 412: ...396 Chapter 28 Bit Search 8 Caution ...
Page 521: ...505 Chapter 30 I O Ports 3 Port Register Settings ...
Page 522: ...506 Chapter 30 I O Ports 3 Port Register Settings ...
Page 574: ...558 Chapter 31 External Bus 4 Endian and Bus Access Byte Access ...
Page 628: ...612 Chapter 31 External Bus 13 Notes on Using the External Bus Interface ...
Page 706: ...690 Chapter 33 I2C Controller 4 Programming Flow Charts ...
Page 748: ...732 Chapter 34 CAN Controller 4 CAN Application ...
Page 762: ...746 Chapter 35 Free Run Timer 8 Caution ...
Page 790: ...774 Chapter 37 Output Compare 8 Caution ...
Page 838: ...822 Chapter 39 Programmable Pulse Generator 8 Caution ...
Page 850: ...834 Chapter 40 Pulse Frequency Modulator 4 PFM Operation and Setting ...
Page 886: ...870 Chapter 42 Sound Generator 3 Registers ...
Page 900: ...884 Chapter 43 Stepper Motor Controller 4 Caution ...
Page 939: ...923 Chapter 47 LCD Controller 3 Configuration Figure 3 2 Register List ...
Page 943: ...927 Chapter 47 LCD Controller 4 Registers Correspondence between VRAM and Common Segment Pins ...
Page 964: ...948 Chapter 48 Clock Monitor 8 Caution ...
Page 994: ...978 Chapter 51 Low Voltage Reset Interrupt 3 Registers ...
Page 998: ...982 Chapter 52 Regulator Control 3 Registers ...
Page 1008: ...992 Chapter 53 Fixed Mode Reset Vector BOOT ROM 5 Bootloader Update Strategy ...
Page 1024: ...1008 Chapter 54 Flash Memory 8 Caution ...
Page 1032: ...1016 Chapter 55 Flash Security 4 Register ...
Page 1034: ...1018 Chapter 56 Electrical Specification ...
Page 1035: ...FR60 MB91460 Series Hardware Manual European Microcontroller Design Centre Author MBo ...
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