LC74731 Sanyo Semicon Device, LC74731 Datasheet - Page 20

• Manufacturer Part Number: LC74731
• Description: On-Screen Display Controller
• Manufacturer: Sanyo Semicon Device

COMMAND50 (Sync signal detection 1 setup command)
• First byte
• Second byte
Note that all registers are set to 0 when these ICs are reset by the RST pin.
DA0 to 7
DA0 to 7
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
Register
Register
DISLIN
RN2
RN1
RN0
SN3
SN2
SN1
SN0
I/E
—
—
—
—
—
—
—
State
State
1
1
0
1
0
0
0
1
0
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Command 5 identification code
Sync signal control settings
Extended command 0 identification code
12 lines
10 lines
External synchronization
Internal synchronization
Second byte identification bit
RN2
SN3 SN2 SN1 SN0
0
0
0
1
0
0
0
0
1
0
0
0
1
0
RN1
0
0
1
0
0
0
1
0
0
RN0 Number of times HSYNC detected
0
1
0
0
Content
Content
0
1
0
0
0
LC74731W,74732W
0 times (32 times)
4 times (64 times)
8 times (128 times)
16 times (256 times)
Function
Function
Number of times HSYNC detected
Not detected
32 times
64 times
128 times
256 times
Switches the number of lines displayed.
Switches between internal and external
synchronization
External sync signal detection control
Recognition of the transition from the no signal
state to the signal present state.
Sets the sampling period in which the sync signal
can be detected continuously in the horizontal sync
signal period (1H).
The values in parentheses apply when RNE0
(COM51) is 1.
External sync signal detection control
Recognition of the transition from the signal
present state to the no signal state.
Sets the sampling period time in which the sync
signal cannot be detected continuously in the
horizontal sync signal period (1H).
Notes
Notes
No. 6526-20/38