Installation guide

Message Routing
890 USE 100 00
197
1 ... 64
If the address is in the range 1 ... 64 (Direct Attach Address), the
message is routed to the specific node address 1 ... 64 on the local
Modbus Plus network.
71 ... 74
If the address is in the range 71 ... 74 (MUX Attach Address), the
message is routed to a single Modbus device at one of the Bridge
Multiplexer’s Modbus ports. Addresses 71 ... 74 specify ports 1 ... 4,
respectively.
80 ... 255
If the address is in the range 80 ... 255 (Implicit Attach Address), it will
be divided by 10. The quotient and remainder of the division will
become the first two bytes of the five byte routing path. The remaining
three bytes will always be zeros. This addressing method allows two
levels of addressing across Modbus Plus networks.
Silent Master Ports
A BM85 serial port can be configured as a Silent Master port. A
network with one master and a set of slave devices can be connected to
the port. The master can initiate communication with a local slave
device or across Modbus Plus. The slave device addresses must be
unique. They must not be the same as a node address (1 ... 64) on the
BM85’s local network, and they must not exist as entries in the
mapping table for the port. Addresses 65 ... 79 are reserved.