Slot 4 Menu 15 − Modbus TCP/IP Setup

Mode: RFC‑S

Modbus TCP/IP is one of the most widely supported industrial Ethernet based protocols offering the functionality and simplicity of the Modbus protocol, with the flexibility of Ethernet. The table below shows the supported Modbus function codes.

The implementation of Modbus TCP/IP follows the specification provided by the Modbus organisation. Modbus TCP/IP uses the standard Protocol Data Unit (PDU) but without the CRC bytes and encapsulates it within a Modbus TCP/IP Application Data Unit (ADU) for transmission. This means that the Modbus PDU is the same for both standard and Ethernet based transmission.

Code Description
3 Read multiple 16 bit registers
6 Write single 16 bit register
16 Write multiple 16 bit registers
23 Read and write multiple 16 bit registers

 


Parameter4.15.001  Enable
Short descriptionSet to enable Modbus functionality
Minimum0Maximum1
Default1Units 
Type1 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter is used to enable or disable Modbus master and slave functionality.


Parameter4.15.002  Reset
Short descriptionSet to reset the interface
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate RateBackground read; written to 0 on initialisation
Display FormatStandardDecimal Places0
CodingRW, NC

This parameter is used to perform a warm reset of the protocol interface. When set and the protocol has reset, the parameter will be reset to zero (Off).


Parameter4.15.003  Default
Short descriptionSet to default the protocol interface
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate RateOn module reset, protocol interface reset or protocol enable
Display FormatStandardDecimal Places0
CodingRW, NC

This parameter allows the protocol to be defaulted to factory settings. This includes all of the protocol features, configuration, mappings and stored objects.


Parameter4.15.004  Modbus Configuration Error
Short descriptionDisplays the Modbus configuration error
Minimum0Maximum3
Default Units 
Type8 Bit VolatileUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRO, TE, ND, NC, PT, BU

ValueTextDescription
0No errorNo error
1Port in useSpecified port is currently in use by another protocol
2Timeout eventTimeout trigger event location is not valid
3Num ConnectionsThe Max priority connection is greater than the max connections

This parameter will indicate any Modbus configuration errors.


Parameter4.15.005  Modbus Listening Port
Short descriptionDefines the Modbus TCP/IP port
Minimum0Maximum65535
Default502Units 
Type16 Bit User SaveUpdate RateMODBUS_THREAD_TICK_TIME
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter can be changed from its default port of 502, however it is the user's responsibility to ensure that a valid port is set.


Parameter4.15.006  Maximum Connections
Short descriptionDefines the maximum number of connections to the module
Minimum0Maximum4
Default2Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter permits the user to specify the total number of connections that one or more clients can open with the module at any one time.


Parameter4.15.007  Maximum Priority Connections
Short descriptionDefines the maximum number of priority connections
Minimum0Maximum4
Default0Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter defines the how many of the maximum connections specified in Maximum Connections (4.15.006) can be configured as a priority connection. A connection is accepted into the priority connections pool if the client's IP address matches one of the values stored in parameters Priority Connection 1 (4.15.020), Priority Connection 2 (4.15.021), Priority Connection 3 (4.15.022) or Priority Connection 4 (4.15.023).

The priority connections are permanent and, once made will only be deleted at the request of the client or due to a communications error.

Any connections not in the priority connections pool are kept in the non-priority connections pool. If a client attempts to establish a priority connection and all available non-priority connections are in use, the non-priority connection that has not been used for the longest will be closed to make way for the new priority connection.


Parameter4.15.008  Maximum Connections Per Client
Short descriptionDefines the maximum number of connections per client
Minimum1Maximum4
Default2Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter defines the maximum number of connections that any one client can establish. This check is only performed on the connections in the priority connections pool.


Parameter4.15.009  Modbus Timeout
Short descriptionDefines the Modbus timeout value
Minimum1Maximum10000
Default100Unitsms
Type16 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, BU

This parameter defines the time period in which the Modbus server must receive a message before any specified action (as defined in ) is performed. When the timeout occurs, bit 1 in the module's alarm parameter () will be set and the specified action will be performed.

The timeout is enabled when the server receives its first message.

Note:
It is good system design to allow for some message loss by setting the timeout duration to be greater than the transmit period by a factor of 2 or more.


Parameter4.15.010  Modbus Timeout Action
Short descriptionDefines the action to perform on a Modbus timeout
Minimum0Maximum1
Default1Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, TE, BU

ValueTextDescription
0TripTrip drive and raise error
1No actionNo action

Defines the action when no message is received within the time period specified in Modbus Timeout (4.15.009).  Note: if a Trip is enabled, this will be triggered by Unidrive M Connect scanning the network since Unidrive M Connect sends a Modbus function code 64. Similar Acyclic Read/Write PC Tools can cause a Timeout Trip for the same reason.

 


Parameter4.15.011  Modbus Timeout Event Destination
Short descriptionDefines the destination for the Modbus timeout event
Minimum0Maximum4
Default0Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, TE, BU

ValueTextDescription
0This slotTrigger event in this slot
1Slot 1Trigger event in slot 1
2Slot 2Trigger event in slot 2
3Slot 3Trigger event in slot 3
4Slot 4Trigger event in slot 4

Defines the destination slot to trigger the event (defined by Modbus Timeout Event Type (4.15.012)) when a timeout occurs.

<< This feature is not currently supported >>


Parameter4.15.012  Modbus Timeout Event Type
Short descriptionDefines the event type to trigger
Minimum0Maximum5
Default0Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, TE, BU

ValueTextDescription
0No eventNo event
1Trigger EventTrigger module Event
2Trigger Event 1Trigger module Event 1
3Trigger Event 2Trigger module Event 2
4Trigger Event 3Trigger module Event 3
5Trigger Event 4Trigger module Event 4

Defines the event to trigger when a timeout occurs. Modbus Timeout Event Destination (4.15.011) must specify an appropriate consumer (slot option) of the event.


Parameter4.15.013  Modbus Register Addressing Mode
Short descriptionDefines the Modbus register addressing mode
Minimum0Maximum1
Default0Units 
Type8 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatStandardDecimal Places0
CodingRW, TE, BU

ValueTextDescription
0Standard(mm x 100) + ppp - mm<=162 and ppp<=99
1Modified(mm x 256) + ppp - mm<=63 and ppp<=255

Specifies the Modbus register addressing mode.


Parameter4.15.020  Priority Connection 1
Short descriptionSpecifies the IP address for the connection
Minimum0
(Display: 0.0.0.0)
Maximum4294967295
(Display: 255.255.255.255)
Default0
(Display: 0.0.0.0)
Units 
Type32 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatIP AddressDecimal Places0
CodingRW, BU

This parameter specifies an IP address for a priority connection.

Note: parameters 20 through 23 must be filled in the order starting from the Priority_Connection_1 thruogh Priority_Connection_4. If a higher numbered Priority Connection is specified without the lower ones being filled, then it will be ignored. 


Parameter4.15.021  Priority Connection 2
Short descriptionSpecifies the IP address for the connection
Minimum0
(Display: 0.0.0.0)
Maximum4294967295
(Display: 255.255.255.255)
Default0
(Display: 0.0.0.0)
Units 
Type32 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatIP AddressDecimal Places0
CodingRW, BU

This parameter specifies an IP address for a priority connection.

Note: parameters 20 through 23 must be filled in the order starting from the Priority_Connection_1 thruogh Priority_Connection_4. If a higher numbered Priority Connection is specified without the lower ones being filled, then it will be ignored.


Parameter4.15.022  Priority Connection 3
Short descriptionSpecifies the IP address for the connection
Minimum0
(Display: 0.0.0.0)
Maximum4294967295
(Display: 255.255.255.255)
Default0
(Display: 0.0.0.0)
Units 
Type32 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatIP AddressDecimal Places0
CodingRW, BU

This parameter specifies an IP address for a priority connection.

Note: parameters 20 through 23 must be filled in the order starting from the Priority_Connection_1 thruogh Priority_Connection_4. If a higher numbered Priority Connection is specified without the lower ones being filled, then it will be ignored.


Parameter4.15.023  Priority Connection 4
Short descriptionSpecifies the IP address for the connection
Minimum0
(Display: 0.0.0.0)
Maximum4294967295
(Display: 255.255.255.255)
Default0
(Display: 0.0.0.0)
Units 
Type32 Bit User SaveUpdate RateModule reset, Modbus interface reset or Modbus interface enable
Display FormatIP AddressDecimal Places0
CodingRW, BU

This parameter specifies an IP address for a priority connection.

Note: fill parameters 20 through 23 from the Priority_Connection_1. If a higher numbered Priority Connection is specified without the lower ones being filled, then it will be ignored.