NJU6625 New Japan Radio Co.,Ltd, NJU6625 Datasheet - Page 4

• Manufacturer Part Number: NJU6625
• Description: Nju6625 12character 1-line Dot Matrix Lcd Controller Driver With Smooth Scroll Function
• Manufacturer: New Japan Radio Co.,Ltd

NJU6625
¢ FUNCTIOAL DESCRIPTION
- 4 -
(1-1) Register
(1-2) Address Counter (AC)
(1-3) Display Data RAM(DD RAM)
(1-4) Character Generator ROM (CG ROM)
(00)
The relation between DDRAM address and display position on the LCD is shown below.
AC
The NJU6625 incorporates two 8 -bit registers, an Instruction Register (IR) and a Data Register (DR).
The Register (IR) stores instruction codes such as “Clear Display” and “Cursor Shift” or address data for
Display Data RAM (DDRAM), Character Generator ROM (CGRAM) and Icon Display RAM (MKRAM).
The Register (DR) is a temporary register, the data in the Register (DR) is written into the DDRAM,
CGRAM or MK RAM.
The data in the Register (DR) written by the MPU is transferred automatically to the DDRAM, CGRAM or
MKRAM by internal operation.
These two registers are selected by the selection signal RS as shown below.
The address counter (A C) addresses the DDRAM, CGRAM or MKRAM.
When the address setting instruction is written into the Register (IR), the address information is
transferred from Register (IR) to the Counter (AC). The selection of either the DDRAM, CGRAM or
MKRAM is also determined by this instruction.
After writing (or reading) the display data to (or from) the DDRAM, CGRAM or MKRAM, the Counter (AC)
increments (or decrements) automatically.
The Display Data RAM (DD RAM)consist of 14 x 8 bits stores up to 14-character display data
represented in 8-bit code. (2 out of the 14-characters are used for scroll RAM.)
The DDRAM address data set in the address counter (AC) is represented in Hexadecimal.
character code.
through (FF)
Table 1. User-defined character patterns (Custom Font) are also available by mask option.
When the display shift is performed, the DDRAM address changes as follows:
The Character Generator ROM (CG ROM) generates 5 x 7 dots character pattern represented in 8-bit
The storage capacity is up to 224 kinds of 5 x 7 dots character pattern (available address is (20)
The correspondence between character code and standard character pattern of NJU6625 is shown in
(Right Shift Display)
(Left Shift Display)
00
0D
01
1
0
01
H
02
00
2
).
AD
3
02
3
03
01
AD
Prelimina ry
03
HEX.
2
4
04
02
AD
04
5
05
03
1
05
AD
6
06
04
0
06
7
07
05
07
8
08
06
08
9
09
07
10
09
Example) DD RAM address ”08”
0A
08
0A
11
0B
09
0
12
0B
0C
0A
1
0C
0D
0B
0
0D
0C
00
8
Scroll RAM
0
Display Position
DD RAM address(Hex.)
(0D)
0
Ver.2008-03-21
H