RFID number not displaying correctly on LCD

[paulenokels]

Hello, I am using PIC18F23K22 to read the tag number of RFID tags, display them on LCD and send the numbers to PC. However, the tag numbers are not displayed correctly on the LCD and I cant receive them on PC. LCD displays something like 'xxxx xxxx fx'. I am using EM-18 RFID reader. Below is my code, Any help will be greatly appreciated

Code: Select all

// Lcd pinout config
sbit LCD_RS at LATA5_bit;
sbit LCD_EN at LATA4_bit;
sbit LCD_D7 at LATA0_bit;
sbit LCD_D6 at LATA1_bit;
sbit LCD_D5 at LATA2_bit;
sbit LCD_D4 at LATA3_bit;

// Pin direction
sbit LCD_RS_Direction at TRISA5_bit;
sbit LCD_EN_Direction at TRISA4_bit;
sbit LCD_D7_Direction at TRISA0_bit;
sbit LCD_D6_Direction at TRISA1_bit;
sbit LCD_D5_Direction at TRISA2_bit;
sbit LCD_D4_Direction at TRISA3_bit;






void main() {
     char rfid_no[13], i, column;

     OSCCON.OSTS = 0;
     OSCCON.IRCF0 = 1;
     OSCCON.IRCF1 = 1;
     OSCCON.IRCF2 = 1;

     ANSELC = 0X00;
     ANSELB = 0X00;

     

     
     TRISB = 0;
     TRISB.RB6 = 0;   //Tx pin
     TRISB.RB7 = 1;  //Rx pin

      TRISC = 0;
     TRISC.RC6 = 0;   //Tx pin
     TRISC.RC7 = 1;  //Rx pin

     LCD_Init();
     LCD_Cmd(_LCD_CLEAR);
     LCD_OUT(1,1, "WELCOME");

     UART2_Init(9600);
    delay_ms(500);
     UART1_Init(9600);
     delay_ms(500);
     UART_Set_Active(&UART2_Read, &UART2_Write, &UART2_Data_Ready, &UART2_Tx_Idle); // set UART2 active
        rfid_no[12] = '\0'; //indicate end of tag number (terminate string)
     while(1) {
     if(UART2_Data_Ready()) { //if data is ready to be read

     
      for (i=0; i<12;) {       //read the tag number one after another
          if (UART2_DATA_READY()) {
          rfid_no[i] = UART2_Read();   //store the tag number
           i++;
          }

      }
      LCD_CMD(_LCD_CLEAR);
      LCD_OUT(1,1, rfid_no);
        UART_Set_Active(&UART1_Read, &UART1_Write, &UART1_Data_Ready, &UART1_Tx_Idle); //SWITCH UART TO PC
        UART1_Write_Text(rfid_no);  //write tag number to PC
        UART1_WRITE(13);
        delay_ms(500);
     }
     else if (UART1_DATA_READY()==1) {   //read response from PC
          res = UART1_Read();
          switch (res) {
           case '0':    //if tag is not registered, PC will return 0
                 LCD_Cmd(_LCD_CLEAR);
                 LCD_Out(1,1, "Unregistered");
                 LCD_Out(2,5, "Tag");
                 UART_Set_Active(&UART2_Read, &UART2_Write, &UART2_Data_Ready, &UART2_Tx_Idle);
           case '1':   //if not enough credit, PC returns 1
                 LCD_Cmd(_LCD_CLEAR);
                 LCD_Out(1,5, "Low");
                 LCD_Out(2,1, "Balance");
                 break;
           case '2':  //IF enough credit, display remaining balance
                 UART1_Write_Text("1");   //send request to get balance
                 UART1_Write(13);
                 delay_ms(100); //wait a while to send
                  LCD_Out(1,2, "Balance");
                 break;
           case 'e': //PC finished sending balance
   
                   UART_Set_Active(&UART2_Read, &UART2_Write, &UART2_Data_Ready, &UART2_Tx_Idle);
            default:
                  balance = UART1_Read(); 
                   LCD_chr(2,column, balance);
                   column++;
          }

          

       }
  }
     }