Modbus Master; Modbus Slave; Function Codes Supported By The Module - ProSoft Technology CompactLogix MVI69E-MBS User Manual

MVI69E-MBS ♦ CompactLogix™ Platform
Modbus Serial Enhanced Communication Module

8.2.1 Modbus Master

A port configured as a virtual Modbus Master actively issues Modbus commands to
other nodes on the Modbus network, supporting up to 250 commands on each port. The
Master ports have an optimized polling characteristic that polls slaves with
communication problems less frequently.
Parameter
Command List
Polling of command list
Status Data

8.2.2 Modbus Slave

A port configured as a Modbus slave permits a remote Master to interact with all data
contained in the module. This data can be derived from other Modbus slave devices on
the network, through a Master port, or from the CompactLogix or MicroLogix 1500-LRP
processor.
Parameter
Node address
Status Data

8.2.3 Function Codes Supported by the Module

The format of each command in the list depends on the Modbus Function Code being
executed. The following table lists the Function Codes supported by the MVI69E-MBS
module.
Function Code
1
2
3
4
5
6
8
15
16
17
22
23
Each command list record has the same general format. The first part of the record
contains the information relating to the communication module and the second part
contains information required to interface to the Modbus slave.
ProSoft Technology, Inc.
Description
Up to 250 commands per Master port, each fully configurable for function,
slave address, register to/from addressing and word/bit count.
Configurable polling of command list, including continuous and on change
of data, and dynamically user or automatic enabled.
Error codes available on an individual command basis. In addition, a slave
status list is maintained per active Modbus Master port.
Description
1 to 247 (software selectable)
Error codes, counters and port status available per configured slave port
Definition
Read Coil Status 0x
Read Input Status 1x
Read Holding Registers 4x
Read Input Registers 3x
Set Single Coil 0x
Single Register Write 4x
Diagnostics
Multiple Coil Write 0x
Multiple Register Write 4x
Report Slave ID
Mask Write 4X
Read/Write
Supported as Master
X
X
X
X
X
X
X
X
Supported as Slave
X
X
X
X
X
X
X
X
X
X
X
X
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Reference
User Manual