NJU6624A/B New Japan Radio Co., Ltd., NJU6624A/B Datasheet - Page 4

• Manufacturer Part Number: NJU6624A/B
• Description: 12-character 1-line Dot Matrix LCD Controller Driver With Smooth Scroll Function
• Manufacturer: New Japan Radio Co., Ltd.

g g FUNCTIONAL DESCRIPTION
(1-1)Register
(1-1)Register
(1-2)Address Counter (AC)
(1-2)Address Counter (AC)
(1-3)Display Data RAM (DD RAM)
(1-3)Display Data RAM (DD RAM)
The NJU6624A/B incorporates two 8-bit registers, an Instruction Register(IR) and a Data Register(DR). The
The NJU6624A/B 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
Register (IR) stores instruction codes such as "Clear Display" and "Cursor Shift" or address data for Display Data
RAM(DD RAM), Character Generator RAM(CG RAM) and Icon Display RAM (MK RAM).
RAM(DD RAM), Character Generator RAM(CG RAM) and Icon Display RAM (MK RAM).
The Register(DR) is a temporary register, the data in the Register(DR) is written into the DD RAM, CG RAM or
The Register(DR) is a temporary register, the data in the Register(DR) is written into the DD RAM, CG RAM or
MK RAM.
MK RAM.
The data in the Register(DR) written by the MPU is transferred automatically to the DD RAM, CG RAM or MK
The data in the Register(DR) written by the MPU is transferred automatically to the DD RAM, CG RAM or MK
RAM by internal operation.
RAM by internal operation.
These two registers are selected by the selection signal RS as shown below.
These two registers are selected by the selection signal RS as shown below.
The address counter(AC) addresses the DD RAM, CG RAM or MK RAM.
The address counter(AC) addresses the DD RAM, CG RAM or MK RAM.
When the address setting instruction is written into the Register(IR), the address information is transferred from
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 DD RAM, CG RAM or MK RAM is also determined by
Register(IR) to the Counter(AC). The selection of either the DD RAM, CG RAM or MK RAM is also determined by
this instruction.
this instruction.
After writing (or reading) the display data to (or from) the DD RAM, CG RAM or MK RAM, the Counter(AC) incre-
After writing (or reading) the display data to (or from) the DD RAM, CG RAM or MK RAM, the Counter(AC) incre-
ments (or decrements) automatically.
ments (or decrements) automatically.
The display data RAM (DD RAM) consist of 14x 8 bits stores up to 14-character display data represented in 8-bit
The display data RAM (DD RAM) consist of 14x 8 bits stores up to 14-character display data represented in 8-bit
code. (2 out of the 14characters are used for scroll RAM.)
code. (2 out of the 14characters are used for scroll RAM.)
The DD RAM address data set in the address counter(AC) is represented in Hexadecimal.
The DD RAM address data set in the address counter(AC) is represented in Hexadecimal.
The relation between DD RAM address and display position on the LCD is shown below.
The relation between DD RAM address and display position on the LCD is shown below.
When the display shift is performed,the DD RAM address changes as follows:
When the display shift is performed,the DD RAM address changes as follows:
( ( 1-4)Character Generator ROM (CG ROM)
The Character Generator ROM (CG ROM) generates 5 x 7 dots character pattern represented in 8-bit character
The Character Generator ROM (CG ROM) generates 5 x 7 dots character pattern represented in 8-bit character
code.
code.
The storage capacity is up to 224 kinds of 5 x 7 dots character pattern(available address is (20)
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 NJU6624A/B is shown in Table 2.
The correspondence between character code and standard character pattern of NJU6624A/B is shown in Table 2.
User-defined character patterns (Custom Font) are also available by mask option.
User-defined character patterns (Custom Font) are also available by mask option.
FUNCTIONAL DESCRIPTION
1-4)Character Generator ROM (CG ROM)
(00)<= 01
A C
( Left Shift Display )
( Left Shift Display )
( Right Shift Display )
( Right Shift Display )
00
0D
Higher
1
A C
4
01
02
00
2
A C
02
03
01
3
3
A C
03
04
02
4
HEX.
HEX.
2
04
05
03
5
A C
1
05
06
04
6
L o w e r
A C
06
07
05
7
0
07
08
06
8
08
09
07
9
0A
10
09
08
(Example) DD RAM address " 08 "
(Example) DD RAM address " 08 "
0A
0B
09
11
0B
0C 0D
0A
12
0C 0D -DD RAM Address (Hex.)
0B
13
|
|
0 0
0
0C =>(0E)
00
14 -Display Position
|
|
1
Scroll RAM
Scroll RAM
NJU6624A/B
NJU6624A/B
0
8 8
0
H H
through (FF)
through (FF)
0
H H
). ).