BAT32G1x9 user manual | Chapter 4 Clock generation circuit
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Rev.1.02
4.8 Vibration stop detection circuit
4.8.1
Vibration stops the function of the detection circuit
Vibration stop detection function is to use the internal low-speed oscillation clock (fIL) to monitor the
operation state of the main system clock (fmx) or the secondary system clock (fsx), in a period of time, when
the action stop is detected, it is judged that the X1 vibration circuit or XT1 vibration circuit is abnormal, and
the output vibration stop detection signal can be used as an interrupt signal or a reset signal.
The vibration stop detection circuit needs to be enabled by software settings after the reset is released.
Vibration stop detection circuit, through the software setting to stop the detection action. Alternatively, the
vibration detection action is stopped because of a terminal reset or other internal reset. After the reset occurs,
the software settings need to be set again to enable the vibration stop detection action.
The vibration stop detection circuit determines the vibration stop time (vibration stop judgment time) is
set by the OSDCCMP11~OSDCCMP0 of the vibration stop detection control register (OSDC).
Oscillation stop determination time = Internal low-speed oscillation clock (fIL) period
╳
((OSDCCMP11~OSDCCMP0 setting value) +1).
Take the internal low-speed oscillation clock (fIL) frequency of 15K as an example:
OSDCCMP11~OSDCCMP0=003H
时
: 232us(MIN.),267us(TYP.),314us(MAX.)
OSDCCMP11~OSDCCMP0=FFFH
时
: 237ms(MIN.),273ms(TYP.),322ms(MAX.)
4.8.2
Composition of the vibration-stop detection circuit
The vibration stop detection circuit consists of the following block diagram.
Fig. 4-29
vibration stop detection circuit (example).
CPU bus
SCMMD
CKSEL
OSDCE
OSDCCMP11-0
f
mx
f
sx
fIL
12 bit counter
counter
clock
oscillation stop
detection output
signal control circuit
match
clear
clear
oscillation stop
detection
interrupt signal
INTOSDC
oscillation stop
detection reset
signal
CLMRES
oscillation stop
detection control
register (SCMCTL)
oscillation stop
detection mode register
(SCMMD)