HD44780U Datasheet, PDF (42/59 Pages) Hitachi Semiconductor – Dot Matrix Liquid Crystal Display Controller/Driver

HD44780U
Table 12 4-Bit Operation, 8-Digit × 1-Line Display Example with Internal Reset
Step
Instruction
No. RS R/W DB7 DB6 DB5 DB4
1 Power supply on (the HD44780U is initialized by the internal
reset circuit)
2 Function set
0 00 0 10
Display
3 Function set
0 00 0 10
0 00 0 * *
4 Display on/off control
_
0 00 0 00
0 01 1 10
5 Entry mode set
_
0 00 0 00
0 00 1 10
6 Write data to CGRAM/DDRAM
H_
1 00 1 00
1 01 0 00
Note: The control is the same as for 8-bit operation beyond step #6.
Operation
Initialized. No display.
Sets to 4-bit operation.
In this case, operation is
handled as 8 bits by initializa-
tion, and only this instruction
completes with one write.
Sets 4-bit operation and
selects 1-line display and 5 × 8
dot character font. 4-bit
operation starts from this step
and resetting is necessary.
(Number of display lines and
character fonts cannot be
changed after step #3.)
Turns on display and cursor.
Entire display is in space mode
because of initialization.
Sets mode to increment the
address by one and to shift the
cursor to the right at the time of
write to the DD/CGRAM.
Display is not shifted.
Writes H.
The cursor is incremented by
one and shifts to the right.
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