hd66712u Renesas Electronics Corporation., hd66712u Datasheet - Page 68

• Manufacturer Part Number: hd66712u
• Description: Dot-matrix Liquid Crystal Display Controller/driver - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

Initializing by Instruction
If the power supply conditions for correctly operating the internal reset circuit are not met, initialization
by instructions becomes necessary.
Initializing when a length of interface is 8-bit system. (See Figure 29.)
Initializing when a length of interface is 4-bit system. (See Figure 30.)
RS
RS
RS
RS
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
• Wait for more than 15 ms
• Wait for more than 40 ms
DB7
DB7
DB7
DB7
Wait for more than 4.1 ms
Wait for more than 100 s
after V
(V
after V
(V
0
0
0
0
0
0
0
CC
CC
DB6
DB6
DB6
DB6
Initialization ends
0
0
0
0
0
0
0
= 5V during operation)
= 3V during operation)
CC
CC
Figure 29 Initializing Flow of 8-Bit Interface
Power on
DB5
DB5
DB5
DB5
rises to 4.5V
rises to 2.7V
1
1
1
1
0
0
0
DB4
DB4
DB4
DB4
1
1
1
1
0
0
0
DB3 DB2 DB1 DB0
DB3 DB2 DB1 DB0
DB3 DB2 DB1 DB0
DB3
N
*
*
*
1
0
0
DB2
*
*
*
0
0
0
1
DB1 DB0
I/D
0
0
*
*
*
*
S
*
*
*
*
0
1
Display off
Display clear
Entry mode set
Function set
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
BF can be checked after the following instructions.
When BF is not checked, the waiting time between
instructions is longer than the execution instruction
time. (See Table 12.)
HD66712U
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