hi,

i have the following code but i get nothing when i try to put TRIGGER signal to D0 and ECHO signal to D1. But when i put TRIGGER and ECHO signal to PORT B pins then it works, can anybody tell me what i am doing wrong?

Below is code:

/* Main.c file generated by New Project wizard
*
* Created:   Fri Aug 16 2019
* Processor: PIC16F877A
* Compiler:  MPLAB XC8
*/

#define _XTAL_FREQ 20000000

#define Trigger RD0
#define Echo RD1
#define RS RD2
#define EN RD3
#define D4 RD4
#define D5 RD5
#define D6 RD6
#define D7 RD7

#include <xc.h>
#pragma config FOSC = HS        // Oscillator Selection bits (HS oscillator)
#pragma config WDTE = OFF       // Watchdog Timer Enable bit (WDT disabled)
#pragma config PWRTE = ON       // Power-up Timer Enable bit (PWRT enabled)
#pragma config BOREN = ON       // Brown-out Reset Enable bit (BOR enabled)
#pragma config LVP = OFF        // Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit (RB3 is digital I/O, HV on MCLR must be used for programming)
#pragma config CPD = OFF        // Data EEPROM Memory Code Protection bit (Data EEPROM code protection off)
#pragma config WRT = OFF        // Flash Program Memory Write Enable bits (Write protection off; all program memory may be written to by EECON control)
#pragma config CP = OFF         // Flash Program Memory Code Protection bit (Code protection off)

//LCD Functions Developed by Circuit Digest.
void Lcd_SetBit(char data_bit) //Based on the Hex value Set the Bits of the Data Lines
{
if(data_bit& 1)
D4 = 1;
else
D4 = 0;
if(data_bit& 2)
D5 = 1;
else
D5 = 0;
if(data_bit& 4)
D6 = 1;
else
D6 = 0;
if(data_bit& 8)
D7 = 1;
else
D7 = 0;
}
void Lcd_Cmd(char a)
{
RS = 0;        
Lcd_SetBit(a); //Incoming Hex value
EN  = 1;      
        __delay_ms(4);
        EN  = 0;      
}
void Lcd_Clear()
{
Lcd_Cmd(0); //Clear the LCD
Lcd_Cmd(1); //Move the curser to first position
}
void Lcd_Set_Cursor(char a, char b)
{
char temp,z,y;
if(a== 1)
{
temp = 0x80 + b - 1; //80H is used to move the curser
z = temp>>4; //Lower 8-bits
y = temp & 0x0F; //Upper 8-bits
Lcd_Cmd(z); //Set Row
Lcd_Cmd(y); //Set Column
}
else if(a== 2)
{
temp = 0xC0 + b - 1;
z = temp>>4; //Lower 8-bits
y = temp & 0x0F; //Upper 8-bits
Lcd_Cmd(z); //Set Row
Lcd_Cmd(y); //Set Column
}
}
void Lcd_Start()
{
  Lcd_SetBit(0x00);
  for(int i=1065244; i<=0; i--)  NOP();
  Lcd_Cmd(0x03);
  __delay_ms(5);
  Lcd_Cmd(0x03);
  __delay_ms(11);
  Lcd_Cmd(0x03);
  Lcd_Cmd(0x02); //02H is used for Return home -> Clears the RAM and initializes the LCD
  Lcd_Cmd(0x02); //02H is used for Return home -> Clears the RAM and initializes the LCD
  Lcd_Cmd(0x08); //Select Row 1
  Lcd_Cmd(0x00); //Clear Row 1 Display
  Lcd_Cmd(0x0C); //Select Row 2
  Lcd_Cmd(0x00); //Clear Row 2 Display
  Lcd_Cmd(0x06);
}
void Lcd_Print_Char(char data)  //Send 8-bits through 4-bit mode
{
   char Lower_Nibble,Upper_Nibble;
   Lower_Nibble = data&0x0F;
   Upper_Nibble = data&0xF0;
   RS = 1;             // => RS = 1
   Lcd_SetBit(Upper_Nibble>>4);             //Send upper half by shifting by 4
   EN = 1;
   for(int i=2130483; i<=0; i--)  NOP();
   EN = 0;
   Lcd_SetBit(Lower_Nibble); //Send Lower half
   EN = 1;
   for(int i=2130483; i<=0; i--)  NOP();
   EN = 0;
}
void Lcd_Print_String(char *a)
{
int i;
for(i=0;a[i]!='\0';i++)
  Lcd_Print_Char(a[i]);  //Split the string using pointers and call the Char function
}
/*****End of LCD Functions*****/
int time_taken;
int distance;
char t1,t2,t3,t4,t5;
char d1,d2,d3;

int main()
{
   TRISDbits.TRISD0 = 0;
   TRISDbits.TRISD1 = 1;
   TRISDbits.TRISD2 = 0;
   TRISDbits.TRISD3 = 0;
   TRISDbits.TRISD4 = 0;
   TRISDbits.TRISD5 = 0;
   TRISDbits.TRISD6 = 0;
   TRISDbits.TRISD7 = 0;

   T1CON=0x20;

    Lcd_Start();
 
    Lcd_Set_Cursor(1,1);
    Lcd_Print_String("Ultrasonic sensor");
    Lcd_Set_Cursor(2,1);
    Lcd_Print_String("with PIC16F877A");
 
    __delay_ms(2000);
    Lcd_Clear();
 
    while(1)
    {
       TMR1H =0;
       TMR1L =0; //clear the timer bits
     
        Trigger = 1;
        __delay_us(10);        
        Trigger = 0;
     
        while (Echo==0);
            TMR1ON = 1;
        while (Echo==1);
            TMR1ON = 0;
     
        time_taken = (TMR1L | (TMR1H<<8));
        distance= (0.0272*time_taken)/2;
         
        time_taken = time_taken * 0.8;
     
        t1 = (time_taken/1000)%10;
        t2 = (time_taken/1000)%10;
        t3 = (time_taken/100)%10;
        t4 = (time_taken/10)%10;
        t5 = (time_taken/1)%10;
        d1 = (distance/100)%10;
        d2 = (distance/10)%10;
        d3 = (distance/1)%10;
     
        Lcd_Set_Cursor(1,1);
        Lcd_Print_String("Time_taken:");
        Lcd_Print_Char(t1+'0');
        Lcd_Print_Char(t2+'0');
        Lcd_Print_Char(t3+'0');
        Lcd_Print_Char(t4+'0');
        Lcd_Print_Char(t5+'0');
     
         Lcd_Set_Cursor(2,1);
        Lcd_Print_String("distance:");
        Lcd_Print_Char(d1+'0');
        Lcd_Print_Char(d2+'0');
        Lcd_Print_Char(d3+'0');   
    }
    return 0;
}

Here is the schematic:

 

Maybe your ranging module does not output a high enough voltage. The minimum logic 1 voltage for PORTD is 4V because it is a Schmitt trigger. PORTB inputs are conventional TTL levels - logic 1 is only 2V. See table 17.2 in the datasheet.
Good luck!