25
LH155BA
2.23. Initialization
The LH155BA is initialized by setting RESB pin to "L".
Normally, RESB pin is initialized together with MPU
by connecting to the reset pin of MPU.
When power is ON, be sure to reset operation.
3. PRECAUTIONS
Precautions when connecting or disconnecting
the power supply
This IC may be permanently damaged by a high
current which may flow if voltage is supplied to the
LCD drive power supply while the logic system
power supply is floating. The details are as follows.
q
When using an external power supply
When connecting the power supply
After connecting the logic system power supply,
make reset operation and then apply external
LCD drive voltages to corresponding pins. (V
0
,
V
1
, V
2
, V
3
, V
4
or V
OUT
, V
R1
and V
R2
)
When disconnecting the power supply
After executing HALT command, disconnect
external LCD drive voltages and then disconnect
the logic system power supply.
w
When using the internal power supply
When connecting the power supply
After connecting the logic system power supply,
make reset operation and then execute PON
command.
When disconnecting the power supply
After executing HALT command, disconnect the
logic system power supply.
It is advisable to connect the serial resistor (50 to
100 $) or fuse to the LCD drive power V
OUT
or V
0
of the system as a current limiter. Set up a suitable
value of the resistor in consideration of the display
grade.
PARAMETER
Display RAM
X-address
Y-address
Display starting line
Display ON/OFF
Display normal/reverse
Display duty
n-line alternating
Common shift direction
Increment mode
REF mode
Data SWAP mode
Register in electronic volume
Power supply
INITIAL STATE
Not fixed
00
H
set
00
H
set
Set at the first line (0
H
)
Display OFF
Normal
1/64
Every frame unit
COM
0
/
COM
63
Increment OFF
Normal
OFF
(1, 1, 1, 1)
OFF