Data transmitting from jd2xx to hijack iOS library

I bought the Hijack Development kit from Seeedstudio, including Hijack main board and programmer daughterboard. After connecting the Hijack main board to the programmer board, I suppose that the data could be transmitted from PC client to libHijack in iPhone/iPad.

Let’s say:

J: jd2xx client on windows 7.

P: programmer board.

H: Hijack main board

L: an iOS library developed for receiving data from the iPhone's audio interface.

The expected data flow: J —>P —>H —>L

While sending some data by jd2xx client, the red LED D5 is lit(looks good) but no response in L(only some noises invoking the callback method).

Did I miss something?

I appreciate any idea or suggestion.

Here is jd2xx code:

    JD2XX jd = new JD2XX();
    try {
        jd.open(0);

        jd.setBaudRate(9200);
        jd.setDataCharacteristics(8, JD2XX.STOP_BITS_1, JD2XX.PARITY_NONE);
        jd.setFlowControl(JD2XX.FLOW_NONE, 0, 0);
        jd.setTimeouts(1000, 1000);

        String msg = "Hey, FDTI Chip!";
        jd.write(msg.getBytes());

        jd.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Here is iOS code:

- (void)viewDidLoad {
    [super viewDidLoad];
    self.hiJackMgr = [HiJackMgr new];
    [self.hiJackMgr setDelegate:self];
}

- (int)receive:(UInt8)data{
    NSString *msg = [NSString stringWithFormat:@"%f", data];
    NSLog(msg);
    dispatch_async(dispatch_get_main_queue(), ^{
        [self.msgLabel setText:msg];
    });
    return data;
}