
7540 Group User
’
s Manual
2-138
APPLICATION
2.9 Oscillation control
Fig. 2.9.6 Control procedure
“
F9
16
”
“
4
F
1
6
”
1
In
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t
i
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a
E
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m
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C
i
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U
n
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X
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a
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e
A
p
r
M
g
l
g
N
)
b
r
a
p
l
P
S
R
f
e
(
-
s
o
e
m
i
e
A
c
c
s
d
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d
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d
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a
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r
m
t
o
a
t
e
s
o
r
o
s
d
o
n
e
s
(
3
B
1
6
)
1
0 0
i
e
o
l
i
l
c
c
i
e
l
l
r
a
a
t
i
m
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n
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c
e
/
R
n
a
C
b
)
l
e
d
(
i
f
o
r
o
s
m
c
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g
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n
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s
c
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l
a
t
o
r
0
0
0
0
0 0
0
0
0
0
1
0
:
:
:
φ
=
φ
=
A
(
N
φ
=
f
f
(
(
p
o
f
(
X
I
X
I
l
i
t
e
X
I
N
)
N
)
e
d
2
)
N
)
/
/
2
8
f
r
o
(
(
H
M
m
i
i
g
d
r
h
d
i
n
-
l
g
s
e
p
-
o
e
s
s
e
p
c
d
e
i
m
d
a
o
m
t
o
d
e
o
)
1
0
e
l
d
e
)
p
r
1
1
:
(
D
o
u
b
l
e
-
s
p
e
e
d
m
o
d
e
)
0
0
0 0
1
“
F
F
1
6
”
“
FF
16
”
1
0
0
1
0
P
r
o
c
e
s
s
i
n
g
0
0
0 0
0
0
0
C
L
I
Read prescaler Y and timer Y and
compare their complement with the setting
values of prescaler Z and timer Z
T
i
m
e
r
Z
i
n
t
e
r
r
u
p
t
p
r
o
c
e
s
s
i
n
g
r
o
u
t
i
n
e
P
r
o
c
e
s
s
i
n
g
RTI
S
e
t
C
P
U
m
o
d
e
r
e
g
i
C
s
t
e
r
P
U
M
(
A
d
d
r
e
s
s
3
B
1
6
)
T
Y
Z
M
(
A
d
d
r
e
s
s
2
0
1
6
)
T
C
S
S
(
A
d
d
r
e
s
s
2
E
1
6
)
T
R
T
i
m
i
n
i
m
e
g
e
r
r
Y
s
Z
c
:
c
i
o
l
l
f
(
u
n
t
o
N
)
t
r
/
s
s
2
o
e
u
l
s
r
c
c
l
e
t
e
e
:
o
a
X
I
e
e
d
t
c
e
d
Timer Y: Timer mode selected
Timer Y count stop
Timer Z: Timer mode selected
Timer Z count stop
Set timer Y, Z mode register
S
e
t
“
0
”
(
(
t
T
t
o
T
o
m
t
i
m
t
h
e
e
h
e
t
Y
t
i
Z
i
m
m
e
n
e
n
r
t
r
t
e
e
Y
r
Z
r
i
n
p
n
u
t
e
t
t
e
p
t
r
d
r
d
r
i
r
i
u
s
u
s
p
a
p
a
t
b
t
b
e
l
e
e
l
e
n
d
n
d
a
)
a
)
b
l
e
b
i
t
.
i
r
i
r
r
u
i
S
e
t
“
0
”
e
b
l
e
b
i
t
.
r
i
Prescaler Y (Address 21
16
)
S
e
t
v
a
l
u
e
t
o
p
r
e
s
c
a
l
e
r
Y
,
t
i
m
e
r
Y
Timer Y (Address 23
16
)
S
e
t
t
i
m
e
r
c
o
u
n
t
s
o
u
r
c
e
s
e
t
r
e
g
i
s
t
e
r
Set value to prescaler Z, timer Z (
Note 3
)
Prescaler Z (Address 25
16
)
i
e
r
Z
p
r
i
m
a
T
m
r
y
(
A
d
d
r
e
s
s
2
7
1
6
)
S
e
t
“
1
”
(
t
T
o
i
t
h
e
e
t
i
m
Z
e
n
r
t
e
Z
r
r
i
u
n
t
e
t
r
e
r
u
n
p
a
t
b
e
l
e
n
d
a
)
b
l
e
b
i
t
.
m
r
i
p
Set
“
0
”
to the timer Y interrupt request bit.
Set
“
0
”
to the timer Z interrupt request bit.
T
Y
Z
M
(
A
d
d
r
e
s
s
2
0
1
6
)
Timer Y count start
Timer Z count start
Set timer Y, Z mode register
Timer Z
divratio
Timer Z
Notes 1:
For the concrete time, ask the oscillator manufacture.
2:
In this example, this setting cannot be selected.
3:
10 ms = 1/4 MHz
2
(F9
16
+ 1)
(4F
16
+ 1)
P
r
e
s
c
a
l
e
r
Z
W
a
i
t
u
n
t
i
l
f
(
X
I
N
)
o
s
c
i
l
l
a
t
i
o
n
i
s
s
t
a
b
i
l
i
z
e
d
(
N
o
t
e
1
)