Hi ya Gunnar,

>Thanks Jim
>
>ja, it looks like down the road 'just' using the comm port would be too limiting. i've started to read through the links you provided - very educational. i tried to understand the equipment needed for a RS-485 solution, but i am afraid i haven't gotten it yet <s>
>
>if i understand it correctly i would hook up (to the comm port) a rs-232 to rs-485 converter?! with this i can control up to 32 external devices (switch 32 light bulbs in the house <s>). if my cables are longer then 4000 feet i need a repeater right.
>

RS-485 is most useful in an industrial environment - long distance, noise immunity, etc. One device usually acts as a master, the rest slaves. Any device can communicate both ways, under the masters control, with only one device 'talking' at a time.

>but, looking at the pictures of a converter, i don't see a place where you could connect 32 cables?! and if there is one, we're talking about low voltage - right. so i need in addition to the converter a relay of some kind to convert from low voltage to 110V right?!
>

Correct. you don't see 32 cables because only one is used. All connections are effectively a T off the main string. And yes, you would need a device to receive the command, decipher the message, and act accordingly.

>so money-wise we're talking about a few hundret bucks to control 2 or 3 devices. does that sound about right?

Maybe - http://www.rs485.com/pmicros.html or http://www.audon.co.uk/relay.html are some early Google hits on some commercial products. Gives you some idea of what is available 'off the shelf'. You just do the switching :-)

>Ps.: i sure like those stamps - they are cool!

Way cool. The only lack I have found is no hardware interrupts. Check out http://www.nutsvolts.com/stmpindx.htm and see what people are doing with these things.