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7540 Group User
’
s Manual
2-144
APPLICATION
2.9 Oscillation control
Fig. 2.9.11 Control procedure
N
o
t
e
s
1
:
A
i
A
t
b
V
C
s
e
o
C
l
e
u
t
=
c
2
e
M
5
d
V
a
H
Timer A division ratio (fixed)
,
s
z
t
/
h
t
e
h
1
t
i
o
=
m
p
e
e
a
r
r
b
a
o
A
i
c
o
t
o
n
1
u
c
2
n
l
5
t
o
s
c
k
o
k
H
u
i
z
r
c
a
e
s
w
f
h
o
e
l
l
n
w
a
s
;
r
i
n
g
o
s
c
i
l
l
a
t
o
r
s
t
e
6
t
u
s
o
2
:
W
a
h
d
e
n
h
i
s
g
e
h
t
-
t
o
i
n
r
g
d
e
t
r
h
e
b
y
v
t
a
e
l
u
f
o
e
l
l
t
o
w
t
i
i
n
m
g
e
.
r
,
s
e
t
i
n
o
r
d
e
r
o
f
l
o
w
-
o
r
d
e
r
b
y
t
e
n
o
3
:
0
.
5
s
=
1
/
1
2
5
k
H
z
T
(
F
e
4
A
2
3
1
s
e
6
t
t
+
n
1
v
)
a
4
:
F
o
r
t
h
e
c
o
n
c
r
e
t
e
t
i
m
e
,
a
s
k
t
h
e
o
s
c
i
l
l
a
t
o
r
m
a
n
u
f
a
c
t
u
r
e
.
Modes 3, 4 (common)
N
S
o
w
s
i
t
i
c
l
l
h
a
i
t
o
o
c
e
i
s
r
a
r
m
e
i
u
c
r
c
t
n
q
i
e
d
R
E
S
E
T
S
C
C
E
I
D
T
L
L
1
0 0
0
0
1
0
CLI
WIT instruction executed
W
a
i
t
m
o
d
e
P
r
o
c
e
s
s
i
n
g
Timer A interrupt processing routine
P
r
o
c
e
s
s
i
n
g
P
r
o
c
e
s
s
i
n
g
1
0 0
0
0
0
0
0
0 0
1
0
0
0
P
r
o
c
e
s
s
i
n
g
1
0 0
1
0
0
0
0 0
0
T
A
M
Count stop
(
A
d
d
r
e
s
s
1
D
1
6
)
Set timer A mode register
0 0
1
R
T
I
T
A
M
i
C
(
A
d
d
r
e
s
s
1
D
1
6
)
T
m
o
e
n
r
m
s
o
t
o
d
p
e
s
e
l
e
c
t
e
d
u
t
S
e
t
t
i
m
0 0
e
r
A
m
o
d
e
r
e
g
i
s
t
e
r
1
“
2
“
F
3
1
6
”
4
1
6
”
T
i
m
e
r
A
(
h
i
g
h
-
o
r
d
e
r
)
[
A
d
d
r
e
s
s
1
F
1
6
]
Set values to timer A (
Notes 2, 3
)
Set
“
0
”
to the timer A interrupt request bit
T
i
m
e
r
A
(
l
o
w
-
o
r
d
e
r
)
[
A
d
d
r
e
s
s
1
E
1
6
]
M
o
d
e
s
3
,
4
O
p
e
r
a
t
i
o
n
m
o
d
e
b
y
c
e
r
a
m
i
c
o
s
c
i
l
l
a
t
i
o
n
N
Y
Switch to double-speed
mode is required
RTS
1
0 0
Ring oscillator oscillation enabled
X
IN
oscillation (ceramic) stop
Applied from ring oscillator
0
0
1
0
O
p
e
r
a
t
i
o
n
m
o
d
e
b
y
c
e
r
a
m
i
c
o
s
c
i
l
l
a
t
i
o
n
M
o
d
e
2
M
o
d
e
1
Mode 2
Y
M
o
d
e
2
Mode 3
Mode 4
In
i
t
i
a
l
i
z
a
t
i
o
n
S
e
t
C
P
U
m
o
d
e
r
e
g
P
S
R
f
C
A
i
s
t
e
r
C
U
n
i
n
X
I
e
p
M
g
l
g
N
)
r
a
p
l
(
-
s
o
A
c
c
s
i
c
d
d
h
i
c
o
f
r
d
p
l
a
i
l
l
s
o
r
m
t
o
a
t
c
m
e
s
o
r
o
l
l
a
r
s
d
o
n
t
i
n
e
s
(
i
o
g
3
B
1
6
)
i
e
o
m
i
e
i
l
c
c
n
o
i
e
l
l
r
a
a
t
i
m
o
n
i
c
e
)
n
s
a
t
o
b
p
l
e
d
(
i
i
s
c
i
l
l
a
t
o
r
(
N
o
t
e
1
)
S
e
t
C
P
U
m
o
d
e
r
e
g
C
i
s
t
e
U
r
M
P
f(X
IN
) oscillation (ceramic) enabled
(
A
d
d
r
e
s
s
3
B
1
6
)
S
e
t
“
0
”
(
t
T
o
m
t
h
e
e
t
A
i
m
e
n
r
t
e
A
r
i
n
p
t
e
t
r
d
r
i
u
s
p
a
t
b
e
l
e
n
d
a
)
b
l
e
b
i
t
.
i
r
i
r
u
i
m
r
i
g
l
u
e
Wait until f(X
IN
) oscillation is stabilized (
Note 4
)
S
e
t
C
P
U
m
o
d
e
r
e
g
P
M
i
s
t
e
r
C
U
d
M
d
(
A
-
s
d
p
d
e
r
e
d
s
m
s
3
d
B
1
e
6
)
D
o
u
b
l
e
-
s
p
e
e
d
m
o
d
e
Set CPU mode register
C
P
U
M
(
A
d
d
r
e
s
s
3
B
1
6
)
Set CPU mode register
C
P
U
M
(
A
d
d
r
e
s
s
3
B
1
6
)
S
e
t
“
0
”
(
“
t
T
0
(
o
m
t
O
t
h
e
e
o
t
h
t
A
t
h
r
i
m
e
i
n
e
n
r
t
e
r
t
i
e
n
r
r
A
r
t
u
i
n
p
r
r
p
s
t
e
t
u
d
r
d
p
i
r
i
t
s
u
s
e
a
p
a
n
b
t
b
a
l
e
l
e
b
e
n
d
l
d
a
)
e
)
b
l
e
b
i
t
.
i
r
o
e
i
r
e
u
S
e
t
”
b
i
t
s
.
TAM(Address 1D
16
)
Count start
Set timer A mode register
i
l
e
e
o