COMM api ParallelPort locks

Question

Hello all,
I'm trying to use the Parallel Port from COMM api just to send 1 byte to Paralell data I/O using the code below,
portList = CommPortIdentifier.getPortIdentifiers();
while (portList.hasMoreElements()) {
portId = (CommPortIdentifier) portList.nextElement();
portId.getPortType());
if (portId.getPortType() == CommPortIdentifier.PORT_PARALLEL) {
try {
parallelPort = (ParallelPort) portId.open("MoodMusic", 2000);
} catch (PortInUseException e) { }
// Writing to port
try {
outputStream = parallelPort.getOutputStream();
outputStream.write("Hello World".getBytes());
} catch (Exception e) { System.out.println(e.getMesssage());}
And the application keep locked when I proceed the write method,
I do not need read anything from Parallel Port and I have no device connected it.
Is it possible to use the ParalelPort class just to send bytes , It is needed something else to work? or It just work for printers.
best regards,

Answer 1

Thank you very much Jos,You're welcome.
But I really do not understand the solution you proposed, I really need
an answer from device or Could I solve it from PC Host?Sun's API expects that nAck negative pulse; if it doesn't arrive it won't
send new data. You either need to fake that pulse (using a bit of
additional hardware triggered by the strobe signal coming from the host)
or maybe (just a quick idea), you could set a small timeout value and
try to send your bytes one by one. This would slow down the communication
speed substantially but you don't need to build special hardware.
If your device is fast enough it would pick up the eight bits of data and
then Sun's API would time out. This way you also lose quite a lot of
functionality like error detection etc.
kind regards,
Jos