When Hyperterm or Teraterm connect to the virtual serial port, the MS driver sends DTR ON to the device (Xmega) in the Set_control_line_state setup packet. When they disconnect, the driver sends DTR OFF to the device. Brays doesn't do this, but you may be able to tell by other means. When Brays disconnects, the driver sends the DTR off but when Brays connects it usually does not send the DTR on. You may be able to detect a connect by other means.

Because of Java's platform-independence, serial interfacing is difficult. Serial interfacing requires a standardized API with platform-specific implementations, which is difficult for Java. Unfortunately, Sun didn't pay much attention to serial communication in Java. Sun has defined a serial communication API, called JavaComm. Also, it has been suggested that recompiling the jcl with the java compiler you have chosen will resolve this issue. As I have never experienced this verification problem, I have no way to test this. It should also be noted that the purpose of this paper is to be a quick and easy way to get serial and parallel port access in Java. Does anyone know how to send text via the serial port to a picaxe chip without having to use the picaxe programming editor i.e programming a chip to. To a PICAXE using any programming language which supports serial communications - Java, C, C++, QBASIC, Visual Basic, FreeBASIC, RealBASIC etc. Mac Programming. Bob Delaney's Science Software. Some very nice Xojo classes and examples. Macintosh OS X, Windows, and some Linux. Serial port support for Java (see Java section below for more). Chipmunk Basic.

In every case, when any terminal connects, the driver sends a whole bunch of Set_line_coding and Get_line_coding setup packets. Apparently the monkey that wrote the driver was getting a banana for every line he wrote. In every case when the terminal program disconnects only one setup packet is sent.

That being the Set_control_line_state with DTR off. By the way, has anyone found the Win7 driver (usbser) reliable? I've never observed it working right for more than 12 hours and it often goes haywire much sooner. Doing a bunch of connects/disconnects will often get the virtual serial port hosed. Gangadhar Tipre Serial Song.

Yes it seems Brays doesn't mess with DTR/RTS normally. I think I saw it set DTR once on it's own, but I can't recreate that. Brays does have a DTR button and a RTS button on the right near the bottom.

If the DTR button is toggled ON, the DTR ON is sent to the device when I click on the Connect button, and DTR OFF is sent when I click Disconnect. The RTS button seems to have a mind of it's own. Normally it does nothing but I did get it to send RTS once, but I can't recreate that. I've got Brays 1.9b. I think that's the latest.

I use the OpenFile API. I've never used.Net. I've not used the dongles much. I believe they use their own driver which is probably better than Microsoft's. I've kept them plugged in unused for a few weeks and they invariably cause a blue screen.

My computers often run for 2 or 3 weeks without a restart. They do go to sleep each night and often during the day.

I think sleep, or more properly, waking from sleep that causes much of the trouble. I want my Xmega to be 'embedded' inside the computer case and permanently plugged in and I want to be able to access it by a communications link at any time. I can do that using rs232, but USB CDC with the current Win7 Microsoft driver is a non-starter. Microsoft modified the driver for Win8 and that seems to be reliable. I had it running for a week and it always worked.

We use.NET serialport for a commercial project. I wrote most of the code myself and found some interesting things..NET is really, really slow if you try to read characters. You need to read small chunks at a time rather than characters or your 3.2GHz quad core PC won't be able to keep up with your 32MHz micro.