¡ Semiconductor
ML9041
Display Data RAM (DDRAM)
This RAM stores the display data represented in 8–bit character coding (see Table 2).
The DDRAM addresses correspond to the display positions (digits) of the LCD as shown below.
The DDRAM addresses (to be set in the ADC) are represented in hexadecimal.
DB6 DB5 DB4 DB3 DB2 DB1 DB0
ADC
MSB
LSB
Hexadecimal
Hexadecimal
(Example) Representation of DDRAM address = 12
ADC
0
0
1
0
0
1
0
1
2
1) Relationship between DDRAM addresses and display positions (1–line display mode)
Digit
1
Display position
2
3
4
5
19 20
12 13
DD RAM address (hexadecimal)
00 01 02 03 04
Left
end
Right
end
In the 1–line display mode, the ML9041 can display up to 20 characters from digit 1 to digit 20.
While the DDRAM has addresses “00” to “4F” for up to 80 character codes, the area not used for
display can be used as a RAM area for general data. When the display is shifted by instruction,
the relationship between the LCD display and the DDRAM address changes as shown below:
Digit
1
2
3
4
19 20
11 12
(Display shifted to the right)
(Display shifted to the left)
4F 00 01 02
Digit
1
2
3
4
5
19 20
13 14
01 02 03 04 05
17/54
OKI [ OKI ELECTRONIC COMPONETS ]
