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WiNG-MGR v2 User Guide
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4.1.
Implementation Basics
The WiNG-MGR is capable of communicating via the half-duplex EIA-485 serial
communication standard. The WiNG-MGR is configured to act as a server device on a
common network. The EIA
-
485 medium allows for multiple devices on a multi-drop network.
The WiNG-MGR is a server only device and will never initiate a communications sequence.
4.1.1 Modes of Transmission
The Modbus protocol uses ASCII and RTU modes of transmission. The WiNG-MGR supports
only the RTU mode of transmission, with 8 data bits, no parity and one stop bit. Every
Modbus packet consists of four fields:
Unit ID Field
Function Field
Data Field
Error Check Field (Checksum)
4.1.1.1 Unit ID Address Field
The unit ID address field is one byte in length and identifies the device involved in the
transaction. A valid address range is between 1 and 254. The unit ID address is set from the
Communications > EIA-485
web page.
4.1.1.2 Function Field
The function field is one byte in length and tells the WiNG-MGR which function to perform.
The supported functions are 03 (Read 4xxxx output registers), 04 (Read 3xxxx input
registers), 06 (Preset single register), 16 (Preset multiple registers).
Summary of Contents for WiNG-MGR v2
Page 4: ...4 WiNG MGR v2 User Guide 800 518 1519 ...
Page 14: ...14 WiNG MGR v2 User Guide 800 518 1519 1 System Overview ...
Page 74: ...74 WiNG MGR v2 User Guide 800 518 1519 5 WiNG RXT ...
Page 78: ...78 WiNG MGR v2 User Guide 800 518 1519 ...
Page 82: ...82 WiNG MGR v2 User Guide 800 518 1519 ...
Page 86: ...86 WiNG MGR v2 User Guide 800 518 1519 C Alternate Channel Pair Communications ...
Page 90: ...90 WiNG MGR v2 User Guide 800 518 1519 D Troubleshooting ...
Page 94: ...94 WiNG MGR v2 User Guide 800 518 1519 E Technical Specifications ...