LH1594 SHARP [Sharp Electrionic Components], LH1594 Datasheet - Page 11

• Manufacturer Part Number: LH1594
• Description: 80-Segment and 17-Common Outputs LCD Driver IC with A Built-in CGROM
• Manufacturer: SHARP [Sharp Electrionic Components]

2.1.4. SERIAL INTERFACE
[FOR LH1594]
The serial interface for the LH1594 is I
format. I
communication between different ICs or other
modules.
LH1594 always operates as a slave device, so
sending data of start and stop is controlled by
start/stop bits which are sent by master device.
[FOR LH1595]
The serial interface of LH1595 can accept inputs of
SDA and SCL in the chip selection state (CSB =
"L"). When not in the chip selection state, the
internal shift register and counter are reset to their
initial condition.
Serial data SDA are input sequentially in order of
D
and are converted into 8-bit parallel data (by serial
to parallel conversion) at the rising edge of the 8th
serial clock, being processed in accordance with
the data.
7
to D
0
2
at the rising edge of serial clock (SCL)
C BUS is for bi-directional two-line
CSB
SDA
SCL
RS
D
1
7
D
2
6
D
3
2
5
C BUS
D
4
4
11
D
5
The identification whether the serial data inputs
(SDA) are display data or commands is judged by
input to RS pin.
After completing 8-bit data transferring, or when
making no access, be sure to set serial clock input
(SCL) to "L".
Protection of SDA and SCL signals against external
noise should be taken in actual wiring. To prevent
the successive recognition errors of transferring
data from external noise, release the chip selection
state (CSB = "H") at every completion of 8-bit data
transferring.
3
RS = "H" : Display data
RS = "L" : Commands
D
6
2
D
7
1
D
8
Valid
0
LH1594/LH1595