Hi Piclisters!

I see a lot of people in the list build PIC networks (i.e. for home =
automation purposes) using RS-485. I also have seen some industrial =
units (sensors, controllers, ...) using someting like a "multidrop" =
current-loop system.=20

Now i'm not sure what i should use when i want to connect several PIC's =
over a long distance? (hundreds of meters)

I prefer the simple and stable (and of course cheap) construction of the =
current-loop sender and receiver units, but have a little worry about =
the total current on the bus when some receivers are connected.

I think about a single (data) wire for TX and RX, simple construction =
with a transistor in the TX part and a optocoupler in the RX part (and =
of couse some resistors and diodes ...).

On the other hand ist pretty simple just to use a chip to interfacing to =
RS-485 Bus.

Has anybody recommendations what to use or some experience with a =
"multidrop current-loop"?

Thank you for your help in advance.

cu, Christian

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