1.2 Set istruzioni

Tabella 2, HD44780 set istruzioni
Instruction Code Description Execution time**
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Clear display 0 0 0 0 0 0 0 0 0 1 Clears display and returns cursor to the home position (address 0). 1.64mS
Cursor home 0 0 0 0 0 0 0 0 1 * Returns cursor to home position (address 0). Also returns display being shifted to the original position. DDRAM contents remains unchanged. 1.64mS
Entry mode set 0 0 0 0 0 0 0 1 I/D S Sets cursor move direction (I/D), specifies to shift the display (S). These operations are performed during data read/write. 40uS
Display On/Off control 0 0 0 0 0 0 1 D C B Sets On/Off of all display (D), cursor On/Off (C) and blink of cursor position character (B). 40uS
Cursor/display shift 0 0 0 0 0 1 S/C R/L * * Sets cursor-move or display-shift (S/C), shift direction (R/L). DDRAM contents remains unchanged. 40uS
Function set 0 0 0 0 1 DL N F * * Sets interface data length (DL), number of display line (N) and character font(F). 40uS
Set CGRAM address 0 0 0

1

CGRAM address Sets the CGRAM address. CGRAM data is sent and received after this setting. 40uS
Set DDRAM address 0 0 1 DDRAM address Sets the DDRAM address. DDRAM data is sent and received after this setting. 40uS
Read busy-flag and address counter 0 1 BF DDRAM address Reads Busy-flag (BF) indicating internal operation is being performed and reads address counter contents. 0uS
Write to CGRAM or DDRAM 1 0 write data Writes data to CGRAM or DDRAM. 40uS
Read from CGRAM or DDRAM 1 1 read data Reads data from CGRAM or DDRAM. 40uS

 

Table 3, Bit names
Bit name Settings
I/D 0 = Decrement cursor position 1 = Increment cursor position
S 0 = No display shift 1 = Display shift
D 0 = Display off 1 = Display on
C 0 = Cursor off 1 = Cursor on
B 0 = Cursor blink off 1 = Cursor blink on
S/C 0 = Move cursor 1 = Shift display
R/L 0 = Shift left 1 = Shift right
DL 0 = 4-bit interface 1 = 8-bit interface
N 0 = 1/8 or 1/11 Duty (1 line) 1 = 1/16 Duty (2 lines)
F 0 = 5x7 dots 1 = 5x10 dots
BF 0 = Can accept instruction 1 = Internal operation in progres