HD44780U Datasheet, PDF (45/59 Pages) Hitachi Semiconductor – Dot Matrix Liquid Crystal Display Controller/Driver

HD44780U
Initializing by Instruction
If the power supply conditions for correctly operating the internal reset circuit are not met, initialization by
instructions becomes necessary.
Refer to Figures 23 and 24 for the procedures on 8-bit and 4-bit initializations, respectively.
Power on
Wait for more than 15 ms
after V_CC rises to 4.5 V
RS R/WDB7 DB6 DB5 DB4 DB3DB2 DB1 DB0
000011****
Wait for more than 4.1 ms
Wait for more than 40 ms
after V_CC rises to 2.7 V
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
RS R/WDB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
000011****
Wait for more than 100 µs
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
RS R/WDB7 DB6 DB5 DB4 DB3 DB2 DB1DB0
000011****
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
RS R/WDB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 0 1 1NF * *
0000001000
0000000001
0 0 0 0 0 0 0 1 I/D S
BF can be checked after the following instructions.
When BF is not checked, the waiting time between
instructions is longer than the execution instuction
time. (See Table 6.)
Function set (Interface is 8 bits long. Specify the
number of display lines and character font.)
The number of display lines and character font
cannot be changed after this point.
Display off
Display clear
Entry mode set
Initialization ends
Figure 23 8-Bit Interface
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