bu9768ak ROHM Co. Ltd., bu9768ak Datasheet - Page 8

• Manufacturer Part Number: bu9768ak
• Description: Driver Segmented Module With Input Function
• Manufacturer: ROHM Co. Ltd.

•
(1) Data communications
The BU9768AK / BU9768AKV are able to receive LCD display data output from the controller, as well as the results
of key scans.
When LCD data is output, the command code “42” must be output at the beginning of the data. Fig. 6 shows an
example of LCD display data output.
q During the time that CS is LOW, the command code “42” is input synchronized to the CK clock, and CS is then set
w The LCD data is sent, and 0 (LOW level) is input for the two bits following D
e An 8-bit control code is input, and CS is set to LOW.
8
1) LCD display data output (from controller)
Standard ICs
Circuit operation
to HIGH before the rise of the next CK clock.
CS
CK
CS
CK
DI
DI
LSB
0
D
121
1
D
122
Command code: 42
1 byte (8 bits)
0
LCD display data
1 byte (8 bits)
A value of 0 LOW must always be input for
the 2 bits following D
D
123
0
D
124
0
D
Fig. 6 Example of LCD display data transmission
125
0
126
D
.
126
1
0
0
MSB
0
D
DP
1
D
S
2
0
LCD display data
1 byte (8 bits)
D
S
3
1
Control code
1 byte (8 bits)
D
K
4
0
D
K
5
1
126
BU9768AK / BU9768AKV
D
.
P
6
0
D
P
7
1
D
SC
8