arduino serial library

Question

I have very simple loop to read serial port and write to client

// telnet defaults to port 23
Server server(23);

void setup() {
    Serial.begin(9600);// opens serial port, sets data rate to 9600 bps

    // initialize the ethernet device
    Ethernet.begin(mac, ip, gateway, subnet);

    // start listening for clients
    server.begin();
}

void loop() {
    if (Serial.available() > 0) {
        char byte = Serial.read();
        server.write(byte);
    }
}

problem happens if serial port is open (on computer side) after ethernet connection is established, no data is transmitted

What gives? thank you

Answer 1

Maybe this is simplistic, but if you open the serial port on the computer, doesn't that make Serial.available() == 0?

You could light the LED on the board if that's true. Hope this helps.

Answer 2

I haven't really used processing but I have used C and I don't understand how you're getting away with having thatchar byte = Serial.read(); in the middle of the function. All variables should be defined at the start of the function and then used.