Why output changed after power off & power on for BL4S100

[:x] [:x] Hi, I have encountered a problem today.
Below is the code I used:
/**********************************************************
Connections:
============
1. Scanner to BL4S100: 2–RxD;3–TxD;5–Gnd.
2. BL4S100 to PLC: 2–RxF/CTS;3–TxF/RTS;5–Gnd.

**********************************************************/
#class auto // Change local var storage default to “auto”

// include BL4S1xx series library
#use “BL4S1xx.lib”

// serial buffer size
#define DINBUFSIZE 15
#define DOUTBUFSIZE 15
#define FINBUFSIZE 15
#define FOUTBUFSIZE 15

// serial baud rate
#ifndef _232BAUD
#define _232BAUD 9600
#endif

main()
{
int input, output, output2;
int i,j,iSend;
char PD_rbuf[DINBUFSIZE];
char PF_tbuf[FINBUFSIZE];

// initialize board (including serial ports)
brdInit();

// open serial ports

serDopen(_232BAUD);
serFopen(_232BAUD);

// Must use serial mode 0 for 3 wire RS232 operation and
// serMode must be executed after the serXopen function(s).
serMode(0);

// initialize parity
serFparity(PARAM_EPARITY);
//serDparity(PARAM_EPARITY);

// Clear serial data buffers
serDwrFlush();
serDrdFlush();
serFwrFlush();
serFrdFlush();

//printf("Start…
");

while (1)
{
i=0;
//Hits the watchdog timer, postponing a hardware reset for 2 seconds
hitwd();
input=serDgetc();

  //Receive data from port D
  if (input!=10 && input !=-1)
  {
     //printf("Received:%c

",input);
//for(j=0;j<1000;j++);
for(i=0;i

Seems the output will be changed in Program mode VS. Auto mode for BL4S100.

Changed the output mode from string to character one by one. Now it works.

This case can be closed.

Thank you.