BAT32G1x9 user manual | Chapter 6 Universal timer unit Timer4/8
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Rev.1.02
6.7 Control of the timer input (TImn).
6.7.1
Structure of the TImn pin input circuit
Signals from the timer input pins are fed into the timer control circuitry through a noise filter and edge detection
circuitry. For pins that need to be noise-cancelling, the corresponding pin noise filter must be set to active. The
structure of the input circuit is as follows.
Figure 6-40
input circuit structure
TImn Pin
noise
filter
edge
detection
interrupt signal of
master control
channel
C
o
u
n
ti
n
g
c
lo
c
k
s
e
le
c
it
o
n
tr
ig
g
e
r
s
e
le
c
ti
o
n
Timer control
circuit
6.7.2
Noise filters
When the noise filter is invalid, synchronization is performed only by the operating clock (f
MCK
) of channel n;
When the noise filter is active, the two clocks are detected to be consistent after synchronization through the operating
clock (f
MCK
) of channel n. In the case of a noise filter ON or OFF at the TM4mn input pin, the waveform after passing
through the noise filter circuit is shown below.
Fig. 6-40 Sampled waveform of the TImn input pin in the case of noise filter ON or OFF
TImn Pin
noise filter ON
noise filter OFF
operational clock(f
MCK
)
Note: The input waveform of the Tlmn pin is used to illustrate the
operation of the noise filter
ON
or
OFF. In actual use, the
input must be made according to
the
Tlmn
input level width
shown in
the
"AC
characteristics".