HD44780 Hitachi Semiconductor (acquired by Renesas), HD44780 Datasheet - Page 16

• Manufacturer Part Number: HD44780
• Description: Dot Matrix Liquid Crystal Display Controller/driver
• Manufacturer: Hitachi Semiconductor (acquired by Renesas)

HD44780U
1. EPROM data outside the character pattern area: Always input 0s.
2. EPROM data in CGRAM area: Always input 0s. (Input 0s to EPROM addresses 00H to FFH.)
3. EPROM data used when the user does not use any HD44780U character pattern: According to the user
Table 3
Notes: 1. EPROM addresses A11 to A3 correspond to a character code.
16
application, handled in one of the two ways listed as follows.
a. When unused character patterns are not programmed: If an unused character code is written into
b. When unused character patterns are programmed as 0s: Nothing is displayed even if unused
Handling unused character patterns
DDRAM, all its dots are lit. By not programing a character pattern, all of its bits become lit. (This is
due to the EPROM being filled with 1s after it is erased.)
character codes are written into DDRAM. (This is equivalent to a space.)
A 1 1
2. EPROM addresses A3 to A0 specify a line position of the character pattern.
3. EPROM data O4 to O0 correspond to character pattern data.
4. EPROM data O5 to O7 must be specified as 0.
5. A lit display position (black) corresponds to a 1.
6. Line 11 and the following lines must be blanked with 0s for a 5
0
A 1 0 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
1
Example of Correspondence between EPROM Address Data and Character Pattern
(5
Character code
0
10 Dots)
1
EPROM Address
0
0
1
0
1
0
1
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
Line
position
0
0
1
1
1
1
0
1
0
0
0
1
0
0
0
1
0
1
0
0
1
1
1
1
0
1
1
1
0
1
0
0
0
0
O 4 O3 O2 O1 O0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
0
0
0
0
0
Data
0
0
1
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
LSB
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
10 dot character fonts.
Cursor position