LCDs connected to the uC

LCDs connected to the microcontroller in 4 bit data bus mode. LCD will require
a total of 7 data lines
3 control lines plus the 4 lines for the data bus in simple control LCD we will set
RW = 0(write only)

- The EN line is called "Enable."
This control line is used to tell the LCD that you are sending it data.

- The RS line is the "Register Select" line.
RS is low (0), the data is to be treated as a command or special instruction
RS is high (1), the data being sent is text data which sould be displayed on the
screen.

- The RW line is the "Read/Write" control line.
RW is low (0), the information on the data bus is being written to the LCD.
RW is high (1), the program is effectively querying (or reading) the LCD.