No... I'm not selling this device!
I've been having some fun with a "box" which plugs into a LAN (or internet, if you can put it at a static IP address).
It has 8 digital inputs, 8 digital outputs. It is from the company called HW group, in Prague.
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I've posted a basic program in Delphi, with sourcecode, which you can use (for free) as a basis for sensing and control applications.
"Read all about it", as they say, at...
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Hope it proves useful.Tom Boyd