[Rxtx] CommPortIdentifier open() method and hardware flow control

[Michael Erskine]

> -----Original Message-----
> From: rxtx-bounces at qbang.org [mailto:rxtx-bounces at qbang.org] On Behalf
> Of Julian Bui
> Sent: 08 February 2009 09:19


> In some of the examples I see the line:
> "portIdentifier.open(this.getClass().getName(),2000);"
> What is that 2000?  There is nothing in the documentation about it.
> There isn't anything in the documentation about a lot of things,
> actually.

Hi Julian,

The RXTX SerialPort, CommPort, CommPortIdentifier, and many other classes are an implementation of the Sun javax.comm API. For JavaDoc for this API take a look at...

http://java.sun.com/products/javacomm/reference/api/index.html

> What is the difference between the two flow control methods in the
> SerialPort class: FLOWCONTROL_RTSCTS_IN and FLOWCONTROL_RTSCTS_OUT.
> These confuse me because I am used to seting "hardware flow control" in
> hyperterminal, and not either the in or the out.  Could someone explain
> what the difference is and how to use them?  I asked a serial port
> programmer what he thought of these and he didn't know.  So I'm in the
> dark.

OK, so the hardware flow control you are used to using in HyperTerminal (maaaan, people still use that? :) ) has the effect of raising and lowering the RTS and CTS pins to inform the other end to go ahead or hang fire. Just switch them both on for the hardware flow control you're looking for.

Regards,
Michael.