LCD1602 Liquid Crystal

It is a dot matrix LCD module specially used to display letters, numbers and symbols.

It is composed of several 5x7 or 5x10 dot matrix character positions.

Pinout

Timing

Steps

Initialize
write command (RS=L) Set display coordinates
and write data (RS=H)

Command to
clear the screen:

Instruction code: 0x01

Enter mode settings:

I/D: 0, the cursor moves left after writing new data; 1, the cursor
moves right after writing new data S: 0, the display screen does not move after writing new data; 1, the display screen moves right by 1 character after writing new data

Common instructions: 0x06

Display switch control:

D: 0, display function off; 1, display function onC
: 0, no cursor; 1, cursorB
: 0, cursor flashing; 1, cursor not flashing

Common instructions: 0x0c

Function settings:

D: 0, data bus is 4 bits; 1, data bus is 8 bits
N: 0, display 1 line; 1, display 2 lines
F: 0, 5×7 dot matrix/each character; 1, 5×10 dot matrix/each character

Common instructions: 0x38

DDRAM

When writing the display address, the highest bit D7 is required to be constant at high level 1.
Actual address: addr + 80H

Common instructions: 0x80 (set starting point)

Application Circuit

Example

sbit LCD1602_E = P2^7;
sbit LCD1602_RW = P2^5;
sbit LCD1602_RS = P2 ^ 6; void LcdWriteCom(uchar com) //write command {
    LCD1602_E = 0; // Enable
    LCD1602_RS = 0; //Select to send command
    LCD1602_RW = 0; //Select write

    LCD1602_DATAPINS = com; //Insert command
    Lcd1602_Delay1ms(1); //Wait for data to stabilize

    LCD1602_E = 1; //Write timing
    Lcd1602_Delay1ms(5); //hold time
    LCD1602_E = 0;
}void LcdWriteData(uchar dat) //Write data {
    LCD1602_E = 0; //Enable clear
    LCD1602_RS = 1; //Select input data
    LCD1602_RW = 0;

    LCD1602_DATAPINS = dat; //Write data
    Lcd1602_Delay1ms(1);

    LCD1602_E = 1;
    Lcd1602_Delay1ms(5);
    LCD1602_E = 0;
}void LcdInit()
{
    LcdWriteCom(0x38); //Open the display
    LcdWriteCom(0x0c); //Turn on the display without displaying the cursor
    LcdWriteCom(0x06); //Write a pointer plus 1
    LcdWriteCom(0x01); //Clear screen
    LcdWriteCom(0x80); //Set the data pointer starting point}