PD17202AGF-011_15 Datasheet, PDF (14/30 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLER WITH LCD CONTROLLER/DRIVER AND KEY SCAN CIRCUIT FOR FPC (FRONT PANEL CONTROLLER)

µPD17202AGF-011
4.2 LCD Display Data Configuration
LCD display data is divided into two parts, A and B, for transmission (refer to Table 4-2 Display Data Table).
The data consists of a command (4 bits), LCD data (40 bits), and LED data (1 bit), or a total of 45 bits (only when
data A is transmitted. Data B consists of 44 bits, excluding LED data (1 bit)).
Figure 4-1. Configuration of Input Data for LCD Display
MSB
b b b bDDD
3 2 1 0 40 39 38
LSB
DDDD
3210
Command
(4 bits)
LCD data
Data A or B
(40 bits)
LED data^Note
(1 bit)
Note D0 (= LED data) is necessary only when data A is transmitted.
The status of the data can be identified by the data of each bit (0 or 1) as shown below.
Data
0
1
Status
Extinguishers
Lights
The last 4 bits of the input data is read at the rising edge of the LOAD pin (pin 28) as a command, and the previous
data is displayed on the LCD when display data input is identified.
When a low level is input to the BLANK pin (pin 42), the LCD display is turned ON (the LED also lights when data
A is transmitted). When a high level is input to the BLANK pin, the LCD display is turned OFF (refer to 5.2 Serial
Data Output).
Setting of the BLANK pin does not affect any operations other than the LCD display.
The LCD display data is extinguished in the initial status (even if the BLANK pin is low level).
The configuration of the LCD display data commands (4 bits of MSB) is shown below.
Table 4-3. Serial Data I/O Commands
b3
0
0
0
0
0
1
1
Others
Command
b2
b1
0
1
0
1
1
0
1
1
1
1
1
0
1
1
Operation
b0
0
Inputs display data (data A)
1
Inputs display data (data B)
×
Outputs key data
0
Inputs display data (A) + outputs key data
1
Inputs display data (B) + outputs key data
×
Outputs key data
×
Outputs key data
Setting prohibited
×: Undefined
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