Connect Tech Blue Heat/Net Sync User Manual
74 Revision 0.03
Multi-drop 4-Wire, Full Duplex Communications:
In a multi-drop 4-wire differntial network, two to 32 devices are connected together. Note that
each RS-485 receiver counts as a device or “load”. In this multi-drop mode of communication, a
master slave protocol must be enforced, that is, all communication is initiated by the master, in
this case a Blue Heat/Net Sync. The communication is “full duplex”, meaning that receive and
transmit traffic occur on different pairs of wires. The Blue Heat/Net Sync can receive and
transmit data from/to a device at the same time.
Basic - Wire, Half Duplex Multi-drop Connection:
In a 2-wire differntial network, two to 32 devices are connected together. Note that each receiver
counts as a device or “load”. In this multi-drop mode of communication a master slave protocol
must be enforced, that is, all communication is initiated by the master, in this case a Blue
Heat/Net Sync. The communication is “half duplex”, meaning that receive and transmit traffic
occur on the same wire. The Blue Heat/Net Sync and devices can not receive data and transmit
data at the same time.
Note that the Re/- and the Trans/- signals are connected together. This is
performed at the DB-9 connectors. All communication between devices occurs over a single pair
of wires; this can lower the cost of wiring your network.
