lcd-012n002a-yyh-et Vishay, lcd-012n002a-yyh-et Datasheet - Page 9

• Manufacturer Part Number: lcd-012n002a-yyh-et
• Description: 12 X 2 Character Lcd
• Manufacturer: Vishay

9
Revision: 20-Jul-11
Busy Flag (BF)
Address Counter (AC)
Display Data RAM (DDRAM)
.Function Description
The LCD display Module is built in a LSI controller, the controller has two 8-bit registers, an
instruction register (IR) and a data register (DR).
The IR stores instruction codes, such as display clear and cursor shift, and address information for
display data RAM (DDRAM) and character generator (CGRAM). The IR can only be written from the
MPU. The DR temporarily stores data to be written or read from DDRAM or CGRAM. When
address information is written into the IR, then data is stored into the DR from DDRAM or CGRAM.
By the register selector (RS) signal, these two registers can be selected.
When the busy flag is 1, the controller LSI is in the internal operation mode, and the next instruction
will not be accepted. When RS=0 and R/W=1, the busy flag is output to DB7. The next instruction
must be written after ensuring that the busy flag is 0.
The address counter (AC) assigns addresses to both DDRAM and CGRAM
This DDRAM is used to store the display data represented in 8-bit character codes. Its extended
capacity is 80 8 bits or 80 characters. Below figure is the relationship between DDRAM addresses
and positions on the liquid crystal display.
RS
AC
(hexadecimal)
0
0
1
1
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
R/W
0
1
0
1
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IR write as an internal operation (display clear, etc.)
Read busy flag (DB7) and address counter (DB0 to DB7)
Write data to DDRAM or CGRAM (DR to DDRAM or CGRAM)
Read data from DDRAM or CGRAM (DDRAM or CGRAM to DR)
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT
AC6 AC5 AC4 AC3 AC2 AC1 AC0
High bits
For technical questions, contact:
Low bits
Operation
9
[e-mail]
Example: DDRAM addresses 4E
1
www.vishay.com/doc?91000
LCD-012N002A-YYH-ET
0
0
1
1
1
Document Number: 37406
0
Vishay