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WiNG-MGR User Guide
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OMMUNICATIONS
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 slave device on a common
network. The EIA-485 medium allows for multiple devices on a multi-drop network. The
WiNG-MGR is a slave 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:
♦
Slave Address Field
♦
Function Field
♦
Data Field
♦
Error Check Field (Checksum)
4.1.1.1 Slave Address Field
The slave address field is one byte in length and identifies the slave device involved in the
transaction. A valid address range is between 1 and 254. The slave address is set from the
Com Port1/Modbus/Bacnet Configuration
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).
Содержание WiNG-MGR
Страница 1: ...Monitoring User Guide WiNG System WiNG MGR WiNG RXT Version 1 3 Firmware Version 3 3 2 ...
Страница 14: ...14 WiNG MGR User Guide 800 518 1519 1 System Overview ...
Страница 68: ...68 WiNG MGR User Guide 800 518 1519 3 Web Interface ...
Страница 74: ...74 WiNG MGR User Guide 800 518 1519 5 WiNG RXT ...
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Страница 94: ...94 WiNG MGR User Guide 800 518 1519 C Alternate Channel Pair Communications ...
Страница 98: ...98 WiNG MGR User Guide 800 518 1519 D Troubleshooting ...