chap12 - Chapter 12:LCD, ADC, And Sensors LCD Pin...

Chapter 12:LCD, ADC, And Sensors

LCD Pin Descriptions

RS Pin
•
RS=0:
–
The instruction command code is selected, allowing the
user to send a command such as clear display, cursor at
home, etc.
•
RS=1:
–
The data register is selected, allowing the user to send data
to be displayed on the LCD.

R/W Pin
•
R/W=0:
–
Allows the user to write information to the LCD.
•
R/W=1:
–
Allows the user to read information from the LCD.

E Pin
•
A high-to-low pulse must applied to pin E in order for
the LCD to latch in the data present at the data pins.
•
The pulse must be a minimum of 450 ns wide.

D0-D7 Pins
•
Display letters and numbers by sending ASCII codes for the
letters A-Z, a-z, and numbers 0-9 to these pins while making
RS=1.
•
Send command codes (see Table 12-2) to the LCD while
making RS=0.
•
Check flag bit to see if the LCD is ready to receive
information by making RS=0 and R/W=1.
–
The LCD is busy if D7=1, and ready to receive new information
otherwise

LCD Command
Codes

Send Command and Data to LCD with
Time Delay

(Cont.)

(Cont.)

LCD Timing

Send Command and Data to LCD with Checking
Busy Flag