This document contains C code for an ARM7-based flood alert system using an LCD display. It includes function definitions for initializing the LCD, writing data and instructions, setting the cursor position, printing strings, and generating delays. The main program loop continuously clears the display, prints status messages, and checks sensor input to play warning messages and indicate flood conditions or normal status on the LCD.

1. // RS = P1.16 //successful programforarm7 basedfloodalertsystemdate 4/4/2013 for
GulabroCOE
// EN = P1.17
// D4 = P1.18
// D5 = P1.19
// D6 = P1.20
// D7 = P1.21
#include "LPC214x.H" // LPC2148
MPU Register
#include <stdio.h>
// Define LCDPinIOMask
#define LCD_RS 0x00010000 // P1.16(0000 0000
0000 000x 0000 0000 0000 0000)
#define LCD_EN 0x00020000 // P1.17(0000 0000
0000 00x0 0000 0000 0000 0000)
#define LCD_D4 0x00040000 // P1.18(0000 0000
0000 0x00 0000 0000 0000 0000)
#define LCD_D5 0x00080000 // P1.19(0000 0000
0000 x000 0000 0000 0000 0000)
#define LCD_D6 0x00100000 // P1.20(0000 0000
000x 0000 0000 0000 0000 0000)
#define LCD_D7 0x00200000 // P1.21(0000 0000
00x0 0000 0000 0000 0000 0000)
#define LCD_DATA (LCD_D7|LCD_D6|LCD_D5|LCD_D4)
#define LCD_IOALL (LCD_D7|LCD_D6|LCD_D5|LCD_D4|LCD_RS|LCD_EN)
#define lcd_rs_set() IOSET1= LCD_RS // RS = 1 (SelectInstruction)
#define lcd_rs_clr() IOCLR1= LCD_RS // RS = 0 (SelectData)

2. #define lcd_en_set() IOSET1= LCD_EN // EN = 1 (Enable)
#define lcd_en_clr() IOCLR1=LCD_EN // EN = 0 (Disable)
// xxxx xxx00000 0000 0000 0000 0000 0000
#define lcd_dir_write() IODIR1|= 0x003F0000 // LCD Data Bus = Write
//#define lcd_dir_read() IODIR1&= 0xFFC3FFFF // LCD Data Bus = Read
#define lcd_clear() lcd_write_control(0x01) // ClearDisplay
#define lcd_cursor_home() lcd_write_control(0x02) // SetCursor= 0
#define lcd_display_on() lcd_write_control(0x0E) // LCD DisplayEnable
#define lcd_display_off() lcd_write_control(0x08) // LCD DisplayDisable
#define lcd_cursor_blink() lcd_write_control(0x0F) // SetCursor= Blink
#define lcd_cursor_on() lcd_write_control(0x0E) // Enable LCD Cursor
#define lcd_cursor_off() lcd_write_control(0x0C) // Disable LCDCursor
#define lcd_cursor_left() lcd_write_control(0x10) // ShiftLeftCursor
#define lcd_cursor_right() lcd_write_control(0x14) // ShiftRightCursor
#define lcd_display_sleft() lcd_write_control(0x18) // ShiftLeftDisplay
#define lcd_display_sright() lcd_write_control(0x1C) // ShiftRightDisplay
/* pototype section */
voidlcd_init(void); //
Initial LCD
voidlcd_out_data4(unsignedchar); // Strobe 4-BitData
to LCD
voidlcd_write_byte(unsignedchar); // Write 1 Byte Data
to LCD
voidlcd_write_control(unsignedchar); // Write Instruction
voidlcd_write_ascii(unsignedchar); // Write LCD Display(ASCII)

3. voidgoto_cursor(unsignedchar); // SetPosition
Cursor LCD
voidlcd_print(unsignedchar*); // PrintDisplayto
LCD
//char busy_lcd(void); // Read
BusyLCD Status
voidenable_lcd(void); // Enable
Pulse
voiddelay(unsignedlongint); // DelayFunction
unsignedlongtemp1,temp2;
/* Main Program Start Here */
intmain(void)
{
lcd_init(); //
Initial LCD
PINSEL0 = PINSEL0 & 0x00000000; //16 bitlowerof port0
PINSEL1 = PINSEL1 & 0x00000000; //16 bithigherof port 0
IODIR0 = IODIR0 |0x00f0FF00; //port0 directionreg32bit
PINSEL2 = PINSEL2 & 0xFFFFFFF7;
IODIR1 = IODIR1 |0x00FF0000;
//Loop PrintMessage to LCD16 x 2 //
while(1)
// LoopContinue
{
lcd_write_control(0x01); // Clear
Display (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); // Set
Cursor Line-1

4. lcd_print("ARM7 Based"); // DisplayLCDLine-1
goto_cursor(0x40); // Set
Cursor = Line-2
lcd_print("FloodAlert "); // DisplayLCDLine-2
delay(100000); // Display
Delay
lcd_write_control(0x01); // Clear
Display (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); //
SetCursor Line-1
lcd_print(" Systemusing"); // DisplayLCDLine-1
goto_cursor(0x40); // Set
Cursor = Line-2
lcd_print("Wireless"); // DisplayLCDLine-2
delay(100000); // Display
Delay
if( IOPIN0=( IOPIN0& 0x00000004 ))
{
{
temp1 = IOPIN0;
temp2 = (temp1& 0x000f0000)>>16 ;
if(temp2==0x00000001)
{
IOSET0 = IOSET0 |0x00001100; //msg1play
delay(100000);
IOCLR0 = IOCLR0 |0x00000100;

5. lcd_write_control(0x01); // Clear
Display (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); // Set
Cursor Line-1
lcd_print("FloodWarning"); // DisplayLCDLine-1
delay(100000); //
DisplayDelay
lcd_write_control(0x01); // Clear
Display (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); // Set
Cursor Line-1
lcd_print("DAMGATE OPEN "); // DisplayLCDLine-1
delay(100000); //
DisplayDelay
}
if(temp2==0x00000002)
{
IOSET0 = IOSET0 |0x00001200; //msg2play
delay(100000);
IOCLR0 = IOCLR0 |0x00000200;
}
if(temp2==0x00000003)
{
IOSET0 = IOSET0 |0x00003400; //msg3play
delay(100000);
IOCLR0 = IOCLR0 |0x00003400;

6. lcd_write_control(0x01); //
ClearDisplay (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); // Set
Cursor Line-1
lcd_print("NORMALCONDITION "); // DisplayLCDLine-1
delay(100000); //
DisplayDelay
lcd_write_control(0x01); // Clear
Display (ClearDisplay,SetDDRAMAddress=0)
goto_cursor(0x00); // Set
Cursor Line-1
lcd_print("DAMGATE CLOSE "); // DisplayLCDLine-1
delay(100000); //
DisplayDelay
}
}
}
}
}
/****************************/
/* Strobe 4-Bit Data to LCD */
/****************************/
voidlcd_out_data4(unsignedcharval)
{
IOCLR1 = (LCD_DATA); // Reset4-
Bit PinData

7. IOSET1 = (val<<18); //
EN,0,RW,RS:DDDD:0000:0000:0000:0000:0000:0000
}
/****************************/
/* Write Data 1 Byte to LCD */
/****************************/
voidlcd_write_byte(unsignedcharval)
{
lcd_out_data4((val>>4)&0x0F); // Strobe 4-BitHigh-
Nibble toLCD
enable_lcd(); //
Enable Pulse
lcd_out_data4(val&0x0F); // Strobe 4-
Bit Low-Nibble toLCD
enable_lcd(); //
Enable Pulse
delay(100000);
//while(busy_lcd()); // WaitLCD
Execute Complete
}
/****************************/
/* Write InstructiontoLCD */
/****************************/

8. voidlcd_write_control(unsignedcharval)
{
lcd_rs_clr(); //
RS = 0 = InstructionSelect
lcd_write_byte(val); // Strobe
CommandByte
}
/****************************/
/* Write Data(ASCII) toLCD */
/****************************/
voidlcd_write_ascii(unsignedcharc)
{
lcd_rs_set(); //
RS = 1 = Data Select
lcd_write_byte(c); // Strobe 1
Byte to LCD
}
/*******************************/
/* Initial 4-BitLCD Interface */
/*******************************/
voidlcd_init()
{
unsignedinti; // LCD
Initial DelayCount
PINSEL2 = 0x00000000; //
GPIO1[31..26] = I/OFunction

9. lcd_dir_write(); //
LCD Data Bus= Write
for(i=0;i<1000;i++); // Power-OnDelay
(15 mS)
IOCLR1 = (LCD_IOALL); // Reset
(RS,RW,EN,4-BitData) Pin
IOSET1 = (LCD_D5|LCD_D4); //
DDDD:EN,RW,RS,0:0000:0000:0000:0000:0000:0000
enable_lcd(); //
Enable Pulse
for(i=0;i<100;i++); // Delay4.1mS
IOCLR1 = (LCD_IOALL); // Reset
(RS,RW,EN,4-BitData) Pin
IOSET1 = (LCD_D5|LCD_D4); //
DDDD:EN,RW,RS,0:0000:0000:0000:0000:0000:0000
enable_lcd(); //
Enable Pulse
for(i=0;i<100;i++); // delay
100uS
IOCLR1 = (LCD_IOALL); // Reset
(RS,RW,EN,4-BitData) Pin
IOSET1 = (LCD_D5|LCD_D4); //
DDDD:EN,RW,RS,0:0000:0000:0000:0000:0000:0000
enable_lcd(); //
Enable Pulse
delay(10000);
//while(busy_lcd()); // WaitLCD
Execute Complete

10. IOCLR1 = (LCD_IOALL); // Reset
(RS,RW,EN,4-BitData) Pin
IOSET1 = (LCD_D5); //
DDDD:EN,RW,RS,0:0000:0000:0000:0000:0000:0000
enable_lcd(); //
Enable Pulse
delay(10000);
//while(busy_lcd()); // WaitLCD
Execute Complete
lcd_write_control(0x28); // FunctionSet
(DL=0 4-Bit,N=12 Line,F=05X7)
lcd_write_control(0x0C); // Displayon/off
Control (EntryDisplay,Cursoroff,CursornotBlink)
lcd_write_control(0x06); // Entry Mode Set
(I/D=1 Increment,S=0CursorShift)
lcd_write_control(0x01); // ClearDisplay
(ClearDisplay,SetDDRAMAddress=0)
for(i=0;i<100000;i++); // WaitCommand
Ready
}
/***************************/
/* Set LCD PositionCursor*/
/***************************/
voidgoto_cursor(unsignedchari)
{
i |= 0x80; //
SetDD-RAMAddressCommand

11. lcd_write_control(i);
}
/************************************/
/* PrintDisplayData(ASCII) toLCD*/
/************************************/
voidlcd_print(unsignedchar*str)
{
inti;
for(i=0;i<16 && str[i]!=0;i++) // 16 CharacterPrint
{
lcd_write_ascii(str[i]); // PrintByte to LCD
}
}
/******************/
/* Wait LCD Ready*/
/******************/
/*char busy_lcd(void)
{
unsignedlongbusy_status; // BusyStatusRead
unsignedinti; // Delay
Count

12. lcd_dir_read(); // LCD Data
Bus = Read
lcd_rs_clr(); //
InstructionSelect
lcd_rw_set(); // Read
Direction
lcd_en_set(); //
Start ReadBusy
for(i=0;i<1000;i++); // Delay
Before Read
busy_status= (IOPIN1&0x80000000); // ReadLCD
Data(DDDD:EN,RW,RS,0:0000:0000:0000:0000:0000:0000)
if(busy_status==0x80000000) // Read& Check
BusyFlag
{
lcd_en_clr(); // Disable
Read
lcd_rw_clr(); //
Default= Write Direction
lcd_dir_write(); // LCD Data
Bus = Write
return1; //
LCD Busy Status
}
else
{
lcd_en_clr(); // Disable
Read
lcd_rw_clr(); //
Default= Write Direction
lcd_dir_write(); // LCD Data
Bus = Write

13. return0; //
LCD ReadyStatus
}
}
*/
/***********************/
/* Enable Pulse toLCD */
/***********************/
voidenable_lcd(void) // Enable
Pulse
{
unsignedinti; // Delay
Count
lcd_en_set(); // Enable
ON
for(i=0;i<400000;i++);
lcd_en_clr(); // Enable
OFF
}
/***********************/
/* DelayTime Function*/
/* 1-4294967296 */
/***********************/
voiddelay(unsignedlongintcount1)
{

14. while(count1>0) {count1--;} // Loop Decrease
Counter
}