LC74723, 74723M
3. COMMAND2 (Vertical display start position and vertical character size setting command)
• First byte
DA
0 to 7
7
6
5
4
3
Register
name
—
—
—
—
—
2
VS20
1
—
0
VS10
State
1
0
1
0
0
0
1
0
0
1
Contents
Function
Command 2 identification code
Set vertical display start position and vertical character size.
1H per dot
2H per dot
1H per dot
2H per dot
Remarks
Second line vertical character size
First line vertical character size
• Second byte
DA Register
0 to 7 name
State
Contents
Function
7
—
0 Second byte identification code
6
FS
5
VP5
(MSB)
4
VP4
0 Crystal oscillator frequency: 2fsc
1 Crystal oscillator frequency: 4fsc
0 If VS is the vertical display start position then:
1
0
5
VS
=
H
×
(2Σ
n
2n
=0
VPn)
1
H: the horizontal synchronization pulse period
0
3
VP3
1
0
2
VP2
1
0
1
VP1
1
0
VP0
(LSB)
0
1
Note: The register states are all set to zero when the LC74723 is reset with the RST pin.
Remarks
The vertical display start position is set by the
6 bits VP0 to VP5.
The weight of the low-order bit is 2H.
4. COMMAND3 (Horizontal display start position and horizontal character size setting command)
• First byte
DA
0 to 7
7
6
5
4
Register
name
—
—
—
—
3
EGP
2
HS20
1
—
0
HS10
State
1
0
1
1
0
1
0
1
0
0
1
Contents
Function
Command 3 identification code
Set horizontal display start position and horizontal character size.
Correction: on
Correction: off
1Tc per dot
2Tc per dot
1Tc per dot
2Tc per dot
Remarks
Trimming specifications when the horizontal
character size is doubled
Second line horizontal character size
First line horizontal character size
No. 4841-8/12