Summary of How to display text on 16×2 LCD using PIC18F4550 Microcontroller
This article details the process of displaying text messages on a 16x2 LCD using a PIC18F4550 microcontroller. It outlines programming steps involving LCD configuration, string storage in a character array, and iterative character transmission via the `lcddata()` function within a loop. The provided C code initializes ports, sets up the LCD in 8-bit mode, and displays the string "EngineersGarage" with a delay between characters.
Parts used in the Display Text on 16x2 LCD Project:
- LCD
- PIC18F4550 Microcontroller
- Preset
Several automated and semi-automated devices require a message to be displayed in order to indicate their working status. In continuation to LCD interfacing with PIC18F4550, this article explains how to display a message or string on a 16×2 character LCD.
Code:
while(data[i]!=’’)
{
lcddata(data[i]);
i++;
Delay_ms(300);
}
Project Source Code
###
// Program to display text on 16×2 LCD using PIC18F4550 Microcontroller
// Configuration bits
/* _CPUDIV_OSC1_PLL2_1L, // Divide clock by 2
_FOSC_HS_1H, // Select High Speed (HS) oscillator
_WDT_OFF_2H, // Watchdog Timer off
MCLRE_ON_3H // Master Clear on
*/
//LCD Control pins
#define rs LATA.F0
#define rw LATA.F1
#define en LATA.F2
//LCD Data pins
#define lcdport LATB
void lcd_ini();
void lcdcmd(unsigned char);
void lcddata(unsigned char);
unsigned char data[20]=”EngineersGarage”;
unsigned int i=0;
void main(void)
{
TRISA=0; // Configure Port A as output port
LATA=0;
TRISB=0; // Configure Port B as output port
LATB=0;
lcd_ini(); // LCD initialization
while(data[i]!=”)
{
lcddata(data[i]); // Call lcddata function to send characters
// one by one from “data” array
i++;
Delay_ms(300);
}
}
void lcd_ini()
{
lcdcmd(0x38); // Configure the LCD in 8-bit mode, 2 line and 5×7 font
lcdcmd(0x0C); // Display On and Cursor Off
lcdcmd(0x01); // Clear display screen
lcdcmd(0x06); // Increment cursor
lcdcmd(0x80); // Set cursor position to 1st line, 1st column
}
void lcdcmd(unsigned char cmdout)
{
lcdport=cmdout; //Send command to lcdport=PORTB
rs=0;
rw=0;
en=1;
Delay_ms(10);
en=0;
}
void lcddata(unsigned char dataout)
{
lcdport=dataout; //Send data to lcdport=PORTB
rs=1;
rw=0;
en=1;
Delay_ms(10);
en=0;
}
###
Circuit Diagrams
Project Components
Project Video
Source: How to display text on 16×2 LCD using PIC18F4550 Microcontroller
- How is the string stored for display?
A string is stored in a character array named data. - What function sends individual characters to the LCD?
The lcddata() function is used to send individual character values. - How does the program know when to stop displaying characters?
The loop runs until the loop counter encounters the null character of the string. - Which oscillator is selected in the configuration bits?
The High Speed (HS) oscillator is selected. - What is the delay time set between displaying characters?
A delay of 300 milliseconds is used between each character. - How are Port A and Port B configured?
Both Port A and Port B are configured as output ports. - What command configures the LCD in 8-bit mode?
The command 0x38 configures the LCD in 8-bit mode, 2 line, and 5x7 font. - Where does the cursor start after initialization?
The cursor position is set to the 1st line and 1st column.
