app2.c

#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <errno.h>
#include <arpa/inet.h>


#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/socket.h>


#define LCD_DEV_PATH         "/dev/lcd_dev"
#define BUFF_SIZE		50


#define INTERVAL         50000


void lcd_convert(char* input, int row) {

   unsigned char hex = 0x00;
   unsigned char cursor = 0x00;
   
   
   instr(0x06);
   cursor = 0x80 | (row + row * 0x40);
   instr(cursor); 
   for (int i = 0; i < strlen(input); i++) {
      hex=0xFF & input[i];
      writedata(hex); 
   }
}

void writedata(unsigned char data) {
   unsigned char instr[2] = { 0x00, 0x00 };
   instr[0] = data & 0xF0;
   instr[1] = (data & 0x0F) << 4;   //data shift
   int lcd_dev;
   lcd_dev = open(LCD_DEV_PATH, O_RDWR);
   usleep(40);
   char buf[0];
   for (int i = 0; i < 2; i++) {
      instr[i] |= (1 << 3); 
      instr[i] |= (1 << 0); 
      instr[i] &= ~(1 << 1); 
      instr[i] |= (1 << 2); 
      buf[0]=instr[i];
      write(lcd_dev, buf, 1);
      instr[i] &= ~(1 << 2); 
      buf[0]=instr[i];
      write(lcd_dev, buf, 1);
      
   }
   
}
void instr(unsigned char instr) {
    
    int k=0;
   unsigned char instr1[2] = { 0x00, 0x00 };
   instr1[0] = instr & 0xF0;
   instr1[1] = (instr & 0x0F) << 4;
   int lcd_dev;
   lcd_dev = open(LCD_DEV_PATH, O_RDWR);
   usleep(40);
    char buf[1];
   for (int i = 0; i < 2; i++) {
      instr1[i] &= ~(1 << 3);
      instr1[i] &= ~(1 << 0);
      instr1[i] &= ~(1 << 1);
      instr1[i] |= (1 << 2); 
      buf[0]=instr1[i];
      write(lcd_dev, buf, 1);
      instr1[i] &= ~(1 << 2); 
      buf[0]=instr1[i];
      write(lcd_dev, buf, 1);
   }
}


int main(void)
{
   int server_socket;
   int client_socket;
   int client_addr_size;

   struct sockaddr_in server_addr;
   struct sockaddr_in client_addr;

   char buff_r[BUFF_SIZE+5];
   char buff_s[BUFF_SIZE+5];

   int lcd_fd;
   char lcd_data;
   lcd_fd = open(LCD_DEV_PATH, O_RDWR);
   
   if(lcd_fd < 0){
      printf("fail to open LCD sensor device\n");
      return 1;
   }

   server_socket = socket(PF_INET, SOCK_STREAM, 0);
   if(server_socket == -1) {
	   printf("server socket fail\n");
	   exit(1);
   }

   memset(&server_addr, 0, sizeof(server_addr));
   server_addr.sin_family = AF_INET;
   server_addr.sin_port = htons(4029);
   server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

   if(bind(server_socket, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {
	   printf("cannot bind server\n");
	   exit(1);
   }

   if(listen(server_socket, 1024) == -1) {
	   printf("cannot listen\n");
	   exit(1);
   }

   listen(server_socket, 3);
   client_addr_size = sizeof(client_addr);
   client_socket = accept(server_socket, (struct sockaddr *)&client_addr, &client_addr_size);

   if(client_socket == -1) {
	   printf("cannot connect to client\n");
	   exit(1);
   }
   
   char a[32]={
        0x34, 0x30, 0x34, 0x30, 0x34, 0x30, 0x24, 0x20, 0x24, 0x20, 0x84, 0x80, 0x4, 0x0,
        0x84, 0x80, 0x4, 0x0, 0xE4, 0xE0, 0x4, 0x0, 0x64, 0x60, 0x84, 0x80, 0x4, 0x0, 0x2D,
        0x29, 0x1D, 0x19};
    char buf[1];
    int data=0;
    
      for(int i=0;i<32;i++){
        buf[0]=a[i];
        lcd_data = buf[0];
        write(lcd_fd, buf, 1);
	lcd_data = '\0';

    }
    while(1){
	recv(client_socket, buff_r, BUFF_SIZE, 0);
	recv(client_socket, buff_s, BUFF_SIZE, 0);
    	lcd_convert(buff_r,0);
	lcd_convert(buff_s,1);
	printf("%s %s\n", buff_r, buff_s);
	sleep(2);
	memset(buff_r, '\0', sizeof(buff_r));
	memset(buff_s, '\0', sizeof(buff_s));
    }	
    sleep(1);


    close(client_socket);
    close(server_socket);
    close(lcd_fd);
    return 0; 
}