ModbusEthernet_04

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Appendix A Additional libraries

WAGO-I/O-PRO32 Version 1.1.0 ModbusEthernet_04.lib - 1

WAGO-I/O-PRO32 library

ModbusEthernet_04.lib

The ModbusEthernet_04.lib library provides the user with the two function

modules, ETHERNET_MODBUSMASTER_UDP andETHERNET_MODBUSMASTER_TCP.

With these modules, a data exchange can be set up with several Modbus TCP /

UDP slaves.

The ETHERNET_MODBUSMASTER_UDP module should be used in

preference, as this enables faster data transfer.

The ETHERNET_TERMINAL_MODBUSSLAVE module is also included in

the library.

This module provides a Modbus server, which maps the Modbus services to a

word array.

Content

ModbusEthernet_04.lib ........................................................................3

ETHERNET_MODBUSMASTER_UDP....................................................3

ETHERNET_MODBUSMASTER_TCP .................................................... 5

ETHERNET_MODBUSMASTER_RTU....................................................7

MB_MASTER_SERIAL_OVER_TCP....................................................... 9

ETHERNET_CLIENT_OPEN_CLOSE....................................................12

IP_ADRESSE ............................................................................................ 13

ETHERNET_TERMINAL_MODBUSSLAVE........................................ 14

ETHERNET_SERVER_OPEN_CLOSE .................................................. 16

typETH_SLAVE_DATEN (data type)...................................................... 17

typSER_ModbusQuery (Data type)........................................................... 18

typSER_ModbusResponse (Data Type) .................................................... 19

enumSER_MB_ERROR (Enumeration) ................................................... 20


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ModbusEthernet_04.lib

ETHERNET_MODBUSMASTER_UDP

WAGO-I/O-PRO32 Library elements

Category: Communications module

Name: ETHERNET_MODBUSMASTER_UDP

Type: Function Function block X Program

Library name: ModbusEthernet_04.lib

Requiered libraries Ethernet.lib

Applicable to: Fieldbus controller 750-842 from FW: 02.02.00(04)Fieldbus controller 750-841

Input parameter: Data type: Comment:

bUNIT_ID BYTE Fills the UnitId field in the Modbus protocolheader.

Use:

- References the slave ID in a serial Modbussub-network.

- Buffer index of the Modbus slave on thePC in conjunction with ActiveMBTSlaveCtl.

bFUNCTION_CODE BYTE The following Modbus function codes aresupported:

FC1: (0x01) read coils

FC2: (0x02) read input discretes

FC3: (0x03) read multiple registers

FC4: (0x04) read input registers

FC5: (0x05) write coil

FC6: (0x06) write single register

FC7: (0x07) read exception status

FC11: (0x0B) get comm event counter

FC15: (0x0F) force multiple coils

FC16 (0x10) write multiple registers

FC23 (0x17) read write multiple registers

wREAD_ADDRESS WORD Modbus address in slave to be read.wREAD_QUANTITY WORD Number of bits or words to be read.

ptREAD_DATA POINTERTO BYTE

Pointer to the local data range in which theread data are stored.

wWRITE_ADDRESS WORD Modbus address in slave to be written.

wWRITE_QUANTITY WORD Number of bits or words to be written.

ptSEND_DATA POINTERTO BYTE

Pointer to the local data range in which thedata to be written are stored.

xSTART BOOL Initiate Modbus telegram

xRESET BOOL Reset internal data

tTIME_OUT TIME Maximum waiting time for the reply telegramfrom the Modbus slave.


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ETHERNET_MODBUSMASTER_UDP

4 ModbusEthernet_04.lib ml00101e WAGO-I/O-PRO32

Return value: Data type: Comment:

xREADY BOOL Data transfer is complete or the waiting timeparameterised in tTIME_OUT has expired.

wERROR WORD 0x0000 Successful0x0001 Illegal function code

0x0002 Illegal data address

0x0003 Illegal data value

0x0004 Slave device failure

0x0005 Acknowledge

0x0006 Slave device busy

0x0007 Negative acknowledge

0x0008 Memory parity error

0x000A Gateway path unavailable

0x000B Gateway target no response

0x0095 Error Socket-Close0x0096 no valid Socket from FW

0x0097 Illegal number of points

0x0098 Internal buffer overrun

0x0099 - TimeOut

bRESPONSE_UNIT_ID BYTE Content of the UnitId field in the Modbusprotocol header of the reply telegram

Graphical description:

Functional description:With the ETHERNET_MODBUSMASTER_UDP module, an Ethernet controller becomes theModbus master.

The number of slaves is only limited by the Modbus protocol.

The ETHERNET_MODBUSMASTER_UDP uses the UDP protocol (User Datagram Protocol)and thus enables data to be exchanged more quickly than the TCP version.


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ETHERNET_MODBUSMASTER_TCP



Name: ETHERNET_MODBUSMASTER_TCPType: Function Function block X Program





strIP_ADDRESS STRING IP address of Modbus slave.

bUNIT_ID BYTE Fills the UnitId field in the Modbus protocolheader.

Use:- References the slave ID in a serial Modbussub-network.


bFUNCTION_CODE BYTE The following Modbus function codes aresupported:












wREAD_ADDRESS WORD Modbus address in slave to be read.

wREAD_QUANTITY WORD Number of bits or words to be read.

ptREAD_DATA POINTERTO BYTE


wWRITE_ADDRESS WORD Modbus address in slave to be written.

wWRITE_QUANTITY WORD Number of bits or words to be written.

ptSEND_DATA POINTERTO BYTE


xSTART BOOL Initiate Modbus telegram

xRESET BOOL Reset internal data

tTIME_OUT TIME Maximum waiting time for the reply telegramfrom the Modbus slave.

Example: t#500ms


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ETHERNET_MODBUSMASTER_TCP



xREADY BOOL Data transfer is complete or the waiting timeparameterised in tTIME_OUT has expired.

wERROR WORD 0x0000 Successful

0x0001 Illegal function code0x0002 Illegal data address



0x0005 Acknowledge






0x0097 Illegal number of points

0x0098 Internal buffer overrun0x0099 TimeOut

bRESPONSE_UNIT_ID BYTE Content of the UnitId field in the Modbusprotocol header of the reply telegram


Functional description:

With the ETHERNET_MODBUSMASTER_TCP module, an Ethernet controller becomes the

Modbus master using the TCP protocol.

The number of slaves is only limited by the Modbus protocol.

The ETHERNET_MODBUSMASTER_TCP module should only be used when this isnecessitated by the remote station. The Beijer E300 operating terminal, for example, supportsonly MODBUS TCP.

The disadvantage of the TCP protocol is its basic connection-orientated concept. As a result of

this, a new connection is set up for each data transfer, which leads to a costly protocoloverhead in terms of time.


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ETHERNET_MODBUSMASTER_RTU



Name: ETHERNET_MODBUSMASTER_RTUType: Function Function block X Program





SOCKET WORD

UNIT_ID BYTE Fills the UnitId field in the Modbus protocolheader.

Use:- References the slave ID in a serial Modbussub-network.


FUNCTION_CODE BYTE The following Modbus function codes aresupported:












READ_REFERENCE WORD Modbus address in slave to be read.

QUANTITY_TO_READ

WORD Number of bits or words to be read.

WRITE_REFERENCE

WORD Modbus address in slave to be written.

QUANTITY_TO_WRITE

WORD Number of bits or words to be written.

TIME_OUT TIME Maximum waiting time for the reply telegramfrom the Modbus slave.

Example: t#500ms

ptRECEIVE_BUFFER POINTERTOARRAY[1..3]

OF BYTE


ptSEND_DATA POINTERTOARRAY[1..3]

OF BYTE


START_FUNCTION BOOL Initiate Modbus telegram


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RESET BOOL Reset internal data


ERROR WORD 0x0000 Successful0x0001 Illegal function code

0x0002 Illegal data address



0x0005 Acknowledge






0x0097 Illegal number of points0x0098 Internal buffer overrun

0x0099 TimeOut

READY BOOL Data transfer is complete or the waiting timeparameterised in tTIME_OUT has expired.

RESPONSE_UNIT_ID BYTE Content of the UnitId field in the Modbusprotocol header of the reply telegram



The ETHERNET_MODBUSMASTER_RTU module is used by:

- ETHERNET_MODBUSMASTER_UDP

- ETHERNET_MODBUSMASTER_TCP


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MB_MASTER_SERIAL_OVER_TCP

WAGO-I/O-PRO32 Library Elements

Category: Communication modules

Name: MB_MASTER_SERIAL_OVER_TCPType: Function Function block X Program

Library Name: ModbusEthernet_04.lib

Libraries used Ethernet.lib

Mod_Com.lib

Applicable to: Fieldbus Controller 750-842 from FW: 02.02.00(04)

Fieldbus Controller 750-841

Inputparameter:

Data type: Comment:

strIP_ADDRESS

STRING IP address of Modbus slave.

iPORT WORD Port no. of Modbus slaveDefault -> 502

xCONNECT BOOL TRUE -> TCP connection is establishedpermanently

FALSE -> TCP connection is onlycontroled via StartFunction

tTIME_OUT TIME max. permissible response time of the slave

Input /output

parameters:

Data type: Comment:

StartFunction BOOL A TRUE at this parameter starts the service specified via"FunctionCode".It is automatically reset by the function block after theservice was performed.

Query typModbusQuery TYPE typSER_ModbusQuery :

STRUCT

SlaveAddress : BYTE;

FunctionCode : BYTE;

StartAddress : UINT;

Quantity : UINT;

Data : ARRAY[0..124]OF WORD;

END_STRUCTEND_TYPE

Response typModbusResponse

TYPE typSER_ModbusResponse :

STRUCT

Error : WORD;




Quantity : UINT;

Data : ARRAY[0..124]OF WORD;

END_STRUCTEND_TYPE


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MB_MASTER_SERIAL_OVER_TCP



Outputparameter:

Data type: Comment:

MB_Error enumSER_MB_ERROR

Error codeTYPE enumSER_MB_ERROR :(

SER_MB_NO_ERROR := 16#00,

SER_MB_NOT_SUPPORTED_FUNCTION := 16#01,

SER_MB_ILLEGAL_DATA := 16#03,

SER_MB_EXTENDED_SLAVE_ERROR := 16#90,

SER_MB_CRC_ERROR := 16#96,

SER_MB_ILLEGAL_NUMBER_OF_POINTS := 16#97,

SER_MB_OVERRUN := 16#98,

SER_MB_TIME_OUT := 16#99

);

END_TYPE

OPEN_Error ETH_ERROR See Ethernet.lib description

Graphical illustration:

Function description:

The "MB_MASTER_SERIAL_OVER_TCP" function block expands the functionality of aprogrammable Ethernet controller to that of a serial MODBUS master, communicating viaEthernet TCP.

Serial Modbus RTU frames with CRC are sent and received in TCP packets.The function block acts as a serial Modbus master.Ethernet is only used as a transport medium.A TRUE signal at input "xCONNECT" enables the TCP connection to be permanently

established (default setting -> FALSE).

With the default setting of this input, the TCP connection is only established via theStartFunction input and is then automatically terminated after the task has been carried out.

Supported MODBUS services:0x01 Read Coil Status0x02 Read Input Status0x03 Read Holding Register

0x04 Read Input Registers0x05 Force Single Coil0x06 Preset Single Registers0x0B Fetch Comm Event Ctr0x0F Force Multiple Coils0x10 Preset Multiple Registers


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Executing Modbus function

The data relevant for the query must be entered into the query structure.

The Modbus function is performed on the rising edge at the StartFunction input.

The response of the slave is stored in the response structure.


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ETHERNET_CLIENT_OPEN_CLOSE


ETHERNET_CLIENT_OPEN_CLOSE



Name: ETHERNET_CLIENT_OPEN_CLOSEType: Function Function block X Program





EN BOOL TRUE -> Open socket

FALSE -> Close socket

IP STRING IP address of remote station

(Modbus slave)PORT WORD Port number of remote station

(Modbus slave)

TCP_PROTOKOLL BOOL TRUE -> Use TCP protocol

FALSE -> Use UDP protocol


ERROR WORD = 0: no errors found

0: error in operation (see ETH_ERRORdata type in Ethernet.lib for details)

SOCKET WORD Handle on current socket



The ETHERNET_CLIENT_OPEN_CLOSE module is used by:

- ETHERNET_MODBUSMASTER_UDP

- ETHERNET_MODBUSMASTER_TCP


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IP_ADRESSE



Name: IP_ADRESSEType: Function X Function block Program





IP_ADR STRING IP address of remote station

(Modbus slave)

Return value: Data type: Comment:IP_ADR WORD IP address of remote station (numeric)



The module converts an IP address

The module is used by:- ETHERNET_MODBUSMASTER_UDP- ETHERNET_MODBUSMASTER_TCP- ETHERNET_CLIENT_OPEN_CLOSE


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ETHERNET_TERMINAL_MODBUSSLAVE


ETHERNET_TERMINAL_MODBUSSLAVE

WAGO-I/O-PRO32 Library elementsCategory: Communications module

Name: ETHERNET_TERMINAL_MODBUSSLAVE

Type: Function Function block X Program





EN BOOL TRUE -> Activate Modbus server

iPORT INT Port on which the Modbus server is to beaccessed.

TCP_PROTOKOLL BOOL TRUE -> TCP server

FALSE -> UDP server

iBIT_OFFSET INT Address from which Modbus bit servicesaccess the data array

tWATCHDOG_TIME TIME The watchdog is started with the firsttelegram from the master. A check is madeas to whether the master sends telegramsregularly. If the master drops out, i.e. thewatchdog triggers, the xWATCHDOG_OKoutput is reset.

Input/Output parameter: Data type: Comment:

aDATA typETH_SLAVE_DATEN

WORD ARRAY [0..ETH_SIZE_SLAVEBUFFER]

Output parameter: Data type: Comment:

xWATCHDOG_OK BOOL Master is sending telegrams.

wERROR WORD 0x0000 No error

0x0001 Unsupported function code

0x0002 Illegal address from master

0x0003 Illegal data from master



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This module is responsible for communication with external Modbus masters

(e.g. various text displays / graphical displays).

For this purpose, the master accesses the aDATA word array presented to themodule.

For bit services (function code 0x01, 0x02, 0x0F), an offset can be specified by meansof the parameteriBIT_OFFSET.

When the bit services are used, the master only accesses the data from the specifiedoffset address (word offset).

Example: iBIT_OFFSET = 10The master writes a bit (coil) to Address 2 using function code 0x0F.We can subsequently retrieve this bit from Bit 1 (counting method 0..15) ofWord 10 (iBIT_OFFSET).

This module supports the following Modbus functions

0x01 Read Coil Status

0x02 Read Input Status 0x03 Read Holding Registers

0x04 Read Input Registers

0x05 Force Single Coil

0x06 Preset Single Register

0x0F Force Multiple Coils

0x10 Preset Multiple Registers

0x17 Read / Write Multiple Registers

Word No. Data

0

1

2

...

255


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ETHERNET_SERVER_OPEN_CLOSE


ETHERNET_SERVER_OPEN_CLOSE



Name: ETHERNET_SERVER_OPEN_CLOSEType: Function Function block X Program





EN BOOL TRUE -> Open socket

FALSE -> Close socket

PORT WORD Port on which the server is to be accessed.

TCP_PROTOKOLL BOOL TRUE -> Use TCP protocolFALSE -> Use UDP protocol


ERROR WORD = 0: no errors found

0: error in operation (see ETH_ERRORdata type in Ethernet.lib for details)

SOCKET WORD Handle on current socket



The ETHERNET_CLIENT_OPEN_CLOSE module is used by:- ETHERNET_TERMINAL_MODBUSSLAVE


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typETH_SLAVE_DATEN (data type)


Category:

Name: typETH_SLAVE_DATENType: Data type X Enumeration


Element: Data type: Description:

typETH_SLAVE_DATEN ARRAY[0..ETH_SIZE_SLAVEBUFFER]OF WORD

Word array foruser data

Declaration:

TYPE

typETH_SLAVE_DATEN : ARRAY[0..ETH_SIZE_SLAVEBUFFER] OF WORD;

END_TYPE

Description:

The size of the field can be varied by "masking" the global constantsETH_SIZE_SLAVEBUFFER (default setting = 255).


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typSER_ModbusQuery (Data type)


typSER_ModbusQuery (Data type)


Category:

Name: typSER_ModbusQueryType: Data type X Enumeration

Name of library: ModbusEthernet_04.lib

Structure:

Element: Data type: Description

SlaveAdress BYTE Address of the slave being queried

FunctionCode BYTE Modbus FunctionCode

StartAddress UINT Target memory address of theinformation

Quantity UINT Quantity of information

Data ARRAY [0..512]OF BYTE

Information(only with write services)

Declaration:

TYPE typModbusQuery :

STRUCT




Quantity : UINT;

Data : ARRAY[0..124] OF WORD; (* Modbus specifies max.125 words in one telegram *)

END_STRUCTEND_TYPE


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typSER_ModbusResponse (Data Type)


Category:

Name: typSER_ModbusResponseType: Data type X Enumeration

Name of library: ModbusEthernet_04.lib

Structure:

Element: Data type: Description

Error WORD Error code from slave

SlaveAdress BYTE Address of the slave being queried

FunctionCode BYTE Modbus FunctionCode

StartAddress UINT Target memory address of theinformation

Quantity UINT Quantity of information

Data ARRAY [0..512]OF BYTE

Information(only with read services)

Declaration:TYPE typModbusResponse:

STRUCT

Error : WORD;




Quantity : UINT;

Data : ARRAY[0..124] OF WORD; (* Modbus specifies max.125 words in one telegram *)

END_STRUCT

END_TYPE


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Documents

ModbusEthernet_04