117
MITSUBISHI MICROCOMPUTERS
M37207MF-XXXSP/FP, M37207M8-XXXSP
M37207EFSP/FP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
and ON-SCREEN DISPLAY CONTROLLER
CRT Clock Selection Register
CRT Control Register 2
Address 020816
Address 020916
b7 b6 b5 b4 b3 b2 b1 b0
CRT control register 2 (CBR) [Address 0208
16
]
B Name Functions
After reset
R
W
CRT Control Register 2
0 I signal output switch bit
(CBR0)
0: I signal output
1: MUTE signal output
0
1
I/TIM1 function switch bit
(CBR1)
0
RW
RW
0
Nothing is assigned. These bits are write disable bits.
When these bits are read out, the values are indeterminate.
R—
0: I output or MUTE output
1: 1/2 clock ouput of timer 1
2
to
7
b7 b6 b5 b4 b3 b2 b1 b0
CRT clock selection register (OP) [Address 0209
16
]
B Name Functions After reset R
W
CRT Clock Selection Register
0, 1 CRT clock
selection bits
(OP0, OP1)
0
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 P7
0
and P7
1
respectively.
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 (See note)
2
to
6
0
0
b1
The clock for display is supplied by connecting RC
or LC across the pins OSC1 and OSC2.
Functions
10
b0
CRT oscillation
frequency
= f(X
IN
)
Notes 1: It is necessary to connect other ceramic resonator or quartz-crystal oscillator across the pins X
IN
and X
OUT
.
2: CC6 is the scnanning line double count mode flag.
0
1
11
RW
R—
CC6
CC6 =
“0” or “1”
CC6 = “0”
CC6 = “0”
1
0—Do not set.
7
0
Fix this bits to “0.”
RW
Nothing is assigned. These bits are write disable bits.
When these bits are read out, the values are “0.”
