I will be building a small network of 4 clients to send one of the=20
house's 4 heating/cooling zones temperature and humidity to a central=20
processor. The client likely will be 18F1320, and the processor 18F4320=20
since I have a few laying around, but could consider something=20
different. The client will also have a LCD display. The processor will=20
based on temperature and humidity sent the house HVAC zone controller=20
and humidifier signals (24VAC) via relays based on current set conditions.

The 4 zone lengths from the processor range from 10 to 50 feet and=20
planning to use cat-5 cable. 2 pair for power to the client, and one=20
pair for RS-485 signal. The network speed can be very slow, even down to=20
300 baud, since 1 message from each client in 1second and a message=20
length of maybe 20 characters at most would be a lot.

The question is: Will a star arrangement work, and what should the=20
terminating resistors be?

As an alternative, to each client, I could use 1 pair of the cat-5=20
outbound and 1 pair inbound, and make it one long (less than 200')=20
network with jumpers at each client to select the continuity to the next=20
client, and the usual terminating resistors at the end.


Trying to keep this very simple and any advice appreciated.
--=20
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