m37280eksp Mitsumi Electronics, Corp., m37280eksp Datasheet - Page 78

• Manufacturer Part Number: m37280eksp
• Description: Single-chip 8-bit Cmos Microcomputer With Closed Caption Decoder And On-screen Display Controller
• Manufacturer: Mitsumi Electronics, Corp.

12.11.3 Dot Size
The dot size can be selected by a block unit. The dot size in vertical
direction is determined by dividing H
trol circuit. The dot size in horizontal is determined by dividing the
following clock in the horizontal dot size control circuit : the clock
gained by dividing the OSD clock source (data slicer clock, OSC1,
main clock) in the pre-divide circuit. The clock cycle divided in the
pre-divide circuit is defined as 1T
The dot size is specified by bits 6 to 3 of the block control register.
Fig. 12.11.14 Block Diagram of Dot Size Control Circuit
Fig. 12.11.15 Definition of Dot Sizes
78
Note: To use data slicer clock, set bit 0 of data slicer control register 1 to “1.”
OSC1
slicer
clock
note)
Data
(See
H
SYNC
C
.
SYNC
in the vertical dot size con-
Synchronous
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
circuit
1 dot
1/2H
M37280MF–XXXSP, M37280MK–XXXSP
Cycle
Cycle
Pre-divide circuit
1T
C
2
3
1H
1T
C
Refer to Figure 12.11.4 (the block control register i), refer to Figure
12.11.6 (the clock control register).
The block diagram of dot size control circuit is shown in Figure 12.11.4.
Notes 1: The pre-divide ratio = 3 cannot be used in the CC mode.
Clock cycle
= 1T
In normal scan mode
2H
2: The pre-divide ratio of the layer 2 must be same as that of the layer 1
3: In the bi-scan mode, the dot size in the vertical direction is 2 times as
by the block control register i.
ompared with the normal mode. Refer to “12.11.13 Scan Mode” about
the scan mode.
C
2T
C
and ON-SCREEN DISPLAY CONTROLLER
3H
OSD control circuit
Horizontal dot size
control circuit
Vertical dot size
control circuit
MITSUBISHI MICROCOMPUTERS
3T
C
Scanning line of F1 (F2)
Scanning line of F2 (F1)
M37280EKSP
Rev. 1.0