Need code for Serial comm using PIC16f877

//author: sp
//date: 07/01/2006
//function: use PC to send 4 character to PIC and when the 4 character is detected as "ABCD" (ASCII), it echo back.
//			 : the "ABCD" sequence have to be correct or it will not echo back to PC.

#include <16F877A.h>
#fuses HS, NOWDT, NOPUT, NODEBUG, NOLVP, NOBROWNOUT, NOCPD, NOPROTECT, NOWRT
#use delay(clock = 20000000)

#use rs232(baud=19200, xmit=PIN_C6, rcv=PIN_C7, ERRORS)

#INT_RDA              //RS232 receive data available
void isr_rs232(){
   int A_char, B_char, C_char, D_char;
   int protocol;  // use as a dummy to make sure the sequence of character received is correct.
   
   A_char = getc();
   if (A_char == 'A'){
      protocol = 1;
   }
   if (protocol == 1){
      B_char = getc();
      if (B_char == '3'){
         protocol = 2;
      }
   }
   if (protocol == 2){
      C_char = getc();
      if (C_char == 'C'){
         protocol = 3;
      }
   }
   if (protocol == 3){
      D_char = getc();
      if (D_char == 'D'){
         protocol = 4;
      }
   }
   if (protocol == 4){
   		putc(A_char); putc(B_char); putc(C_char); putc(D_char);	//echo back the character u send to your PIC
	}
   protocol = 0; //clear the dummy for further use.
}

void main(){
   enable_interrupts(GLOBAL);
   enable_interrupts(INT_RDA);
   while(1){
   		;	//do nothing and wait for rs232 interrupt
	}
}

http://bray.velenje.cx/avr/terminal

Error[141] D:\Project32\Serial2.c 6 : can't open include file "16f877a.h": No such file or directory

#use delay(clock = 20000000)

#use delay(clock = 16000000)