LCD Interfacing with 8051 Microcontroller

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LCD Interfacing with 8051 Microcontroller
There are variety of displays available though 16*2 LCD is widely used display device in embedded system. We will discuss about how to interface 16*2 LCD (rows=2, columns=16) with 8051 microcontroller. We will use uvision keil for programming and Proteus for circuit designing of the circuit.

Basic Commands:                                                                            


Pin Description:


           Circuit Diagram:
   


Embedded C Code:

While programming you should follow these steps:
·        STEP1: Initialization of LCD.
·        STEP2: Sending commands to LCD.
·        STEP3: Writing the data to LCD.

Initializing LCD                                  

To initialize LCD to the 8051 the following instruction and commands are to be embed in to the functions
·        0x38 is used for 8-bit data initialization.
·        0xoC for making LCD display on and cursor off.
·        0X01 for clearing the display of the LCD.
·        0x80 for positioning the cursor at first line .

Sending Commands to the LCD

·        E=1; enable pin should be high
·        RS=0; Register select should be low for sending commands
·        Placing the data on the data registers
·        R/W=0; Read/Write pin should be low for writing the data.

Writing the Data to the LCD

·        E=1; enable pin should be high
·        RS=1; Register select should be high for writing data
·        Placing the data on the data registers
·        R/W=0; Read/Write pin should be low for writing the data.

#include<reg51.h>
/* Configure the data bus and Control pins as per the hardware connection
   Databus is connected to P2_0:P2_7 and control bus P0_0:P0_2*/
#define LcdDataBus  P2
sbit LCD_RS = P0^0;
sbit LCD_RW = P0^1;
sbit LCD_EN = P0^2;
/* local function to generate delay */
void delay_us(int cnt)
{
    int i;
    for(i=0;i<cnt;i++);
}
/* Function to send the command to LCD */
void LCD_CmdWrite( char cmd)
{
    LcdDataBus=cmd;    // Send the command to LCD
    LCD_RS=0;          // Select the Command Register by pulling RS LOW
    LCD_RW=0;          // Select the Write Operation  by pulling RW LOW
    LCD_EN=1;          // Send a High-to-Low Pusle at Enable Pin
    delay_us(10);
    LCD_EN=0;
    delay_us(1000);
}
/* Function to send the Data to LCD */










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