Missing 0xFF data when using RXTX

I’m using a Digi Port Server II with the RealPort serial driver in a RedHat Linux OS. Our application is written in Java and is using the RXTX serial implementation (rxtx-2.1.7). We’ve found that when a 0xFF is sent by the device and received by our application that the 0xFF is missing in the response along with some surrounding bytes. This only happens in a Linux environment; using the same Java application and Digi Port Server II accessed via RealPort drivers in a Windows environment and it works fine.

One suggestion that we tried was to turn off the serial port’s inpck flag (strip parity bit) which seems like it would solve our problem (refer to this post: http://forums.digi.com/support/forum/printthread_thread,9376. However it turns out that for some reason this flag always gets reset whenever we use the RXTX serial driver. I’m inclined to say this is a RXTX issue but I’d like to post here to see whether there are any suggestions or a way to prevent this flag from being reset.


Try using the ditty command which comes with the Linux realport driver. I believe it allows you to set sticky settings.

ditty --help
ditty -inpck /dev/ttyxx00