2.1.2Routing to Host Based Network Adapters
or host based network adapters, the byte following the adapter's network node address specifies a task number (1 ... 8) to which the message is assigned. Subsequent bytes are not checked by the adapter, and are available for custom use to the application - for example, for message counts or status information.
2.1.3Routing to BM85 Bridge/Multiplexers
Routing to Serial Ports on BM85 Programmable Models
or the programmable models, the user application stored in the BM85 defines the addressing between Modbus Plus and the serial ports.
Routing to a Single Slave Device on BM85 Modbus Models
or a single slave device at a Modbus port, two bytes are used to address the device. The
igure 5 shows an example of routing to a single slave device.
BP85 | BM85 | BM85 | ZERO | ZERO | |
ADDRESS | ADDRESS | PORT | |||
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(1 ... 64) | (1 ... 64) | (1 ... 4) |
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Figure 5 Modbus Plus Routing to Single Modbus Slave
Routing to a Networked Slave Device on BM85 Modbus Models
or a slave device on a Modbus network at a Modbus port, three bytes are used to address the device. The third byte from the last
igure 6 shows an example of routing to a networked slave device.
BP85 | BM85 | BM85 | SLAVE | ZERO | |||||
ADDRESS | ADDRESS | PORT | ADDRESS | ||||||
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(1 ... | 64) | (1 ... | 64) | (1 ... | 4) | (1 ... | 247) |
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Figure 6 Modbus Plus Routing to Networked Modbus Slave
31007492 | Device Addressing and Message Routing | 19 |