Hi i'm begginer in java,in my project datalogger is connected to com port i have to send 15 integer value to port then other device will send back 15 as a response,now i'm writing to outputstream but i'm not getting response.how to solve this problem plz help me.(i'm using javax.com package)

thanks for reply

+1  A: 

You have to get an InputStream as well, you can't read from the OutputStream. Or am I missing something?

Also, remember to do OutputStream.flush() after writing your output, otherwise your data might be buffered to be sent later - if the responder is waiting for your data, this is most likely where things goes wrong.

Having said that: the javax.comm package is really old. Last time I worked with it, it almost seemed deprecated by Sun, or at least not maintained in any way. You might want to look at other solutions (SerialIO comes to mind).