On 9/25/06, aliensrcooluk at yahoo.co.uk <aliensrcooluk at yahoo.co.uk> wrote: I seem to recall downloading the command format from their website. Keep looking. Did you try downloading the SDK through the Developers tab? Maybe there's a document in there. If you can't find it you can always use a machine with two serial ports (serial protocol analyzer to snoop the traffic. HP serial protocol analyzers up to 19200bps units go pretty cheap on ebay these days if you want a stand-alone. This is not a task you can con someone else into doing if it ain't already done (well, you could pay them, I guess). It is a challenge that you will have to meet yourself if you cannot find documentation. -- John.