I finally found geiger.pl, a perl script to read the port for incoming data, and write it to a file. It provided the working and simple sample code to bootstrap my efforts.

I now have working code for doing I/O, both send and receive, so it is a major victory. I had a little difficulty getting the port configured correctly as it kept giving me an obtuse error message. But I finally licked that too.

The only thing holding me back now is figuring out how to end the read, given that I don't necessarily know what the response is going to be. But I think I am making good progress.

Thanks for the response,

Nathan