Input USART data into array

// This code will read in the USART data and store the result
// in an array.

 const short n = 20;
 char rxchar, i = 0, flag = 0; // Variable for storing the data from UART and array counter
 unsigned char rxarray[n];   // array to store the received charaters

void interrupt () {
  if (PIR1.RCIF) {          // test the interrupt for uart rx
    rxchar = Usart_Read();  //
    rxarray[i] = rxchar;
    i++;
    // ******************************************************
    // Only select one of the following statements
    if (rxchar == 36) {  // select this if looking for a terminating character
    //if (i == n) (         // select this if looking for a number of characters
      flag = 1;
      } // end if (rxchar == "$")
    } // end  if (PIR1.RCIF)
  } // end interrupt


void main () {
unsigned short j;

 INTCON.GIE = 1;
 INTCON.PEIE = 1;
 PIE1.RCIE = 1; //enable interrupt.
 Usart_Init(9600);

 while(1) {   // Begin endless loop
  // This section is where you tell the program what to do with the data once it
  // has all arrived
  if (flag ==1) {
    j = 0;
    while(j < i) {
     Usart_Write(rxarray[j]);
     j++;
     } // end while(rxarray[i])
    i = 0;
    flag = 0;
  } // end if (flag)
  //************************
  // You can place other things to do in your program here
  // i.e. ADC_readings, turn on outputs, etc.
  // ***********************

 } // end while
} // end main