
ML62Q1000 Series User's Manual
Chapter 6
Clock Generation Circuit
FEUL62Q1000
6-18
Figure 6-6 describes backup mode waveforms at the start of the low-speed crystal clock and in the STOP/STOP-D mode.
The low-speed crystal oscillation circuit operates when choosing it through the low-speed clock mode register (FLMOD)
following the start of low-speed RC oscillation circuit operation after the power supply is turned on. Since the FLMOD
register is only initialized by the POR (power-on reset), the oscillation will continue even if a reset other than POR
occurs after choosing the low-speed crystal.
When choosing the external low-speed oscillation circuit through the FLMOD register, The state on the LSI transfers to
the backup mode and the internal low-speed RC oscillation clock is supplied until the low-speed crystal oscillation starts.
Then, after waiting for the low-speed crystal oscillation start time (T
XTL
) and low-speed crystal oscillation stabilization
time (8192 counts), the clock backup interrupt (CBUINT) occurs if the low-speed crystal properly started up. At this
point, release the backup mode. Once the backup mode is released, the crystal oscillation clock is supplied to the
low-speed clock (LSCLK).
In addition, the low-speed crystal oscillation circuit stops oscillation when entering the STOP/STOP-D mode. It resumes
the oscillation by releasing the STOP/STOP-D mode due to external interrupts and etc.. As it transfers to the backup
mode after releasing the STOP/STOP-D mode, release the backup mode following the aforementioned same procedure.
See Chapter 4 "Power Management" for the STOP/STOP-D mode.
See the data sheet for the low-speed oscillation start time (T
XTL
).
Figure 6-6 Low-speed Crystal Oscillation Circuit Operation
(When Low-speed Crystal Starting Up, in STOP/STOP-D Mode)
T
XTL
: Crystal oscillation
start time
External interrupt occurred
RC oscillation waveform
Low-speed RC
oscillation
waveform
Clock backup
interrupt
(CBUINT)
Power supply
V
DD
LOSCS
LOSCB
T
RCL
: RC oscillation start time
Low-speed
clock
512 counts (approx. 16 ms)
CPU operation start
RC oscillation
waveform
SFR setting
Crystal oscillation waveform
8192 counts (approx.
250 ms)
Crystal
oscillation
waveform
Write "1"
STOP/STOP-D
mode
T
XTL
: Crystal oscillation start time
Crystal oscillation waveform
8192 counts (approx.
250 ms)
RC oscillation waveform
T
RCL
: RC oscillation start time
RC
oscillation
waveform
10 counts (approx. 320 μs)
CPU operation start
Write "1"
Crystal oscillation
waveform
CBUINT does not
occur at these timing
POR
(power-on
reset)
Summary of Contents for ML62Q1000 Series
Page 17: ...Chapter 1 Overview...
Page 112: ...Chapter 2 CPU and Memory Space...
Page 154: ...Chapter 3 Reset Function...
Page 166: ...Chapter 4 Power Management...
Page 196: ...Chapter 5 Interrupts...
Page 248: ...Chapter 6 Clock generation Circuit...
Page 274: ...Chapter 7 Low Speed Time Base Counter...
Page 291: ...Chapter 8 16 Bit Timer...
Page 320: ...Chapter 9 Functional Timer FTM...
Page 382: ...Chapter 10 Watchdog Timer...
Page 402: ...Chapter 11 Serial Communication Unit...
Page 456: ...Chapter 12 I2 C Bus Unit...
Page 491: ...Chapter 13 I2 C Master...
Page 512: ...Chapter 14 DMA Controller...
Page 531: ...Chapter 15 Buzzer...
Page 550: ...Chapter 16 Simplified RTC...
Page 559: ...Chapter 17 GPIO...
Page 594: ...Chapter 18 External Interrupt Function...
Page 612: ...Chapter 19 CRC Generator...
Page 632: ...Chapter 20 Analog Comparator...
Page 644: ...Chapter 21 D A Converter...
Page 655: ...Chapter 22 Voltage Level Supervisor...
Page 676: ...Chapter 23 Successive Approximation Type A D Converter...
Page 709: ...Chapter 24 Regulator...
Page 714: ...Chapter 25 Flash Memory...
Page 743: ...Chapter 26 Code Option...
Page 750: ...Chapter 27 LCD Driver...
Page 788: ...Chapter 28 On Chip Debug Function...
Page 795: ...Chapter 29 Safety Function...
Page 813: ...Appendix A...
Page 881: ...Revision History...