M37212 Mitsubishi, M37212 Datasheet - Page 62

• Manufacturer Part Number: M37212
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
• Manufacturer: Mitsubishi

8.10.3 Clock for OSD
As a clock for display to be used for OSD, it is possible to select one
of the following 4 types.
•
•
•
• Clock from the ceramic resonator or the quartz-crystal oscillator
This OSD clock for each block can be selected by the CRT clock
selection register (address 00ED
When selecting the main clock, set the oscillation frequency to
8 MHz.
Fig. 8.10.10 Block Diagram of OSD Selection Circuit
62
Main clock supplied from X
Main clock supplied from X
Clock from the ceramic resonator or the LC or oscillator from the
pins OSC1 and OSC2
supplied from the pins OSC1 and OSC2.
C R T C l o c k S e l e c t i o n R e g i s t e r
b 7 b 6 b 5 b 4 b 3 b 2 b 1 b 0
0
0
0
0
0
N o t e : I t i s n e c e s s a r y t o c o n n e c t o t h e r c e r a m i c r e s o n a t o r o r q u a r t z - c r y s t a l o s c i l l a t o r a c r o s s t h e p i n s X
IN
IN
0
pin
pin divided by I.5
16
).
2 t o 7
0 , 1 C R T c l o c k
B
C R T c l o c k s e l e c t i o n r e g i s t e r ( C K ) [ A d d r e s s 0 0 E D
s e l e c t i o n b i t s
( C K 0 , C K 1 )
F i x t h e s e b i t s t o “ 0 . ”
M37212M4/M8–XXXSP, M37212M6–XXXSP/FP
N a m e
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
b 1
1
0
0
1
b 0
0
1
1
0
S i n c e t h e m a i n c l o c k i s u s e d a s t h e
c l o c k f o r d i s p l a y , t h e o s c i l l a t i o n
f r e q u e n c y i s l i m i t e d . B e c a u s e o f t h i s ,
t h e c h a r a c t e r s i z e i n w i d t h ( h o r i z o n t a l )
d i r e c t i o n i s a l s o l i m i t e d . I n t h i s c a s e ,
p i n s O S C 1 a n d O S C 2 a r e a l s o u s e d
a s i n p u t p o r t s P 3
T h e c l o c k f o r d i s p l a y i s s u p p l i e d b y c o n n e c t i n g R C
o r L C a c r o s s t h e p i n s O S C 1 a n d O S C 2 .
T h e c l o c k f o r O S D i s s u p p l i e d b y c o n n e c t i n g t h e
f o l l o w i n g a c r o s s t h e p i n s O S C 1 a n d O S C 2 .
• a c e r a m i c r e s o n a t o r o n l y f o r O S D a n d a f e e d b a c k
• a q u a r t z - c r y s t a l o s c i l l a t o r o n l y f o r O S D a n d a
r e s i s t o r
f e e d b a c k r e s i s t o r ( S e e n o t e)
6
a n d P 3
F u n c t i o n s
F u n c t i o n s
1 6
7
]
r e s p e c t i v e l y .
with ON-SCREEN DISPLAY CONTROLLER
MITSUBISHI MICROCOMPUTERS
O S D o s c i l l a t i o n
f r e q u e n c y
= f ( X
O S D o s c i l l a t i o n
f r e q u e n c y
= f ( X
I N
I N
)
) / 1 . 5
M37212EFSP/FP
A f t e r r e s e t R W
I N
a n d X
0
0
O U T
R W
R W
.
Rev. 1.0