M37220M3-010SP MITSUBISHI [Mitsubishi Electric Semiconductor], M37220M3-010SP Datasheet - Page 38

• Manufacturer Part Number: M37220M3-010SP
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER?
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

38
(10) Clock for Display
As a clock for display to be used for CRT display, it is possible to
select one of the following 4 types.
•
•
•
•
This clock for display can be selected for each block by the CRT
clock selection register (address 00ED
When selecting the main clock, set the oscillation frequency to
8 MHz.
Table 10. Set value of CRT clock selection register and clock for display
Note: It is necessary to connect other ceramic resonator or quartz-crystal oscillator across the pins X
Main clock supplied from the X
Main clock supplied from the X
Clock from the LC or RC supplied from the pins OSC1 and OSC2.
Clock from the ceramic resonator or quartz-crystal oscillator sup-
plied from the pins OSC1 and OSC2.
b1
0
0
1
1
b0
0
1
0
1
The clock for display is supplied by connecting RC or LC across the pins OSC1 and OSC2.
Since the main clock is used as the clock for display, the oscillation frequency is limited. Because
of this, the character size in width (horizontal) direction is also limited. In this case, pins OSC1
and OSC2 are also used as input ports P3
The clock for display is supplied by connecting the following across the pins OSC1 and OSC2.
• a ceramic resonator only for CRT display and a feedback resistor
• a quartz-crystal oscillator only for CRT display and a feedback resistor (Note)
IN
IN
pin
pin divided by 1.5
16
).
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
3
and P3
4
respectively.
Functions
Fig. 40. Structure of CRT clock selection register
7
0 0
0
0 0 0
with ON-SCREEN DISPLAY CONTROLLER
MITSUBISHI MICROCOMPUTERS
IN
M37220M3-XXXSP
0
and X
Display clock selection bits
Fix these bits to “0.”
CRT clock selection register
(CK : address 00ED
Refer to Table 10.
OUT
CRT oscillation frequency =
f(X
CRT oscillation frequency =
f(X
.
IN
IN
)
)/1.5
16
)