I want to try and contribute back to the LinuxMCE project, but I need a little push in getting going. I found a great multizone amplifier to push audio throughout my house from Home Theater Direct (http://www.htd.com/s.nl/it.A/id.632/.f) They sent me the Serial SDK. It looks like I should be able to write a perl wrapper for it, but I have never programmed any serial control devices. I have done a lot with XML and EDI, so this doesn't look more difficult, just different. My biggest issue is determining what the input and output should look like. I am a little confused on the checksums and TX versus RX. Additionally, is there any caveats to opening and closing the serial port. Can anyone give me some advice on how to get started?