Operation Manual

Simply Modbus TCP Client

Modbus TCP Client Software

System Requirements:

Windows NT, 95, 2000, XP. - (mixed results with Windows 7 and Vista )

display resolution: 800 x 600 minimum

PC with serial port (built in, serial card or USB serial port)
 

Installation - Simply Modbus TCP 1.3.6 (1.64 MB) :

Click to download  SimplyModbusTCP1.3.6.zip

Unzip the compressed files into a common folder on your hard drive.

Simply Modbus TCP 1.3.6.exe - the program
readme TCP.txt                        - documentation

Known Issues with version 1.3.6:  Two instances normally appears in the taskbar while the program is running, the runtime engine and the program iself, Sometimes the runtime engine does not quit when the program is closed, although it is not consistent and behaves differently on different PCs. It is more likely to happen when the program is opened and closed within a few seconds. Waiting longer or sending a request before closing may help it quit properly.  It may quit by itself after a few minutes on some Windows 7 and Vista systems. Although it's okay on others.

Work Arounds: It can be forced to quit by right clicking on the taskbar item and selecting close. This is not a probem for most users. Using Alt-F4 to quit the program also works better in some cases.

Simply Modbus TCP 7.0 looks and runs exactly like Simply Modbus TCP 1.3.6 but was created using a newer compiler. It is a significantly larger download and has an install program. It appears to be more stable with the newer Windows versions.

It will automatically use a license for Simply Modbus TCP 1.3.6 if already installed on the PC.

Installation - Simply Modbus TCP 7.0 (8.59 MB):

click to download  SimplyModbusTCP7.0Install.zip

Unzip the compressed files into a common folder on your hard drive.

setup.exe                          - the install program
setup.ini
data.cab
install.msi
InstMsi.exe
InstMsiW.exe
Readme TCP.txt            - documentation

- Run setup.exe to start the Simply Modbus TCP 7.0 Installation Wizard

- Follow the prompts. The program will start automatically when the installation is complete.

- Running setup.exe a second time will uninstall the program.

Starting the program

Double-click on Simply Modbus TCP 1.3.6.exe. (or select Simply Modbus TCP 7.0 from the Start Menu)

You will see the demonstration startup window.

The progress bar will take approximately 15 seconds to load the demonstration version.
During this time, you can press the ENTER KEY and see

After purchasing and receiving a license key by email, enter the key and press OK.

The licensed program
               - goes immediately to the main Simply Modbus Read window and bypasses the Loading Demo startup window.
               - allows unlimited reads and writes.

The demo version
               - offers full functionality
               - requires a program restart to send more than four read requests or two write commands.

The Simply ModbusTCP Read Window

Controls (inputs) that can be changed by the user are shown in yellow.
Indicators (outputs) shown in blue cannot be changed.

Set the controls to build the Request string.

            Select TCP or RTU-over-TCP mode.  more info...

      Select the IP Address of the Server (Slave device) that you wish to connect to.
                  Select the Server's Port to connect to.

      Press the Connect button and the program will attempt to connect to the Modbus Server.
                                   Each 6 second attempt will count up on the button after the word CONNECTING.
                                   The program will keep trying to connect until a connection is made or the button is pressed again.
      The connection status is displayed as CONNECTED or NOT CONNECTED.

         The 7th byte in the Request string in TCP Mode (The 1st byte in RTU-over-TCP mode)
                   The unit address of the Server (Slave) device to get data from.  normal range:  1 to 247 more info...

                  Setting a Slave ID over 255 will automatically check this box and allow Slave IDs up to 65535.   more info...
                              Remains on for all addresses until the Slave ID is lowered below 256 and the box manually unchecked.

        The 8th byte in the Request string in TCP Mode (The 7th byte in RTU-over-TCP mode
                    Can be automatically set  more info...
                    Used to select which table to read from.  more info...
                    Read Window supports Function codes 01, 02, 03 & 04

         The 9th & 10th bytes in the Request string in TCP Mode (The 3rd & 4th bytes in RTU-over-TCP mode)
                           The coil or register number at the start of the block to read.    more info...

                               This value is subtracted from the First Register to give the data address used in the Request.

        The 11th & 12th bytes in the Request string. in TCP Mode (The 5th & 6th bytes in RTU-over-TCP mode)
                        The quantity of registers or coils in the block to read.

         check to automatically set the default values function code, offset and register size
                         when the value of First Register is changed.

                          The size of the registers in the block to be read.
                                                 This value should be set to 16 bit registers to read standard modbus registers.
                                                 and set to 1 bit coils to read standard modbus coils.
                                                 32 bit registers should be used for Enron modbus only. more info...

                  Events:   This box is checked when reading Enron events from register 32  more info...

                  History:   This box is checked when reading Enron historical records from register 701-799  more info...

          
  TCP Mode                                                 RTU-over-TCP Mode

crc  In RTU-over-TCP Mode, the last 2 bytes of the Request are the cyclic redundancy check.  These are error detection bytes.
       They are not present in TCP Mode  more info...

Auto Set values:

First Register	function code	minus offset	register size
1 to 10000	1	1	1 bit coils
10001 to 10000	2	10001	1 bit coils
30001 to 40000	4	30001	16 bit registers
40001 & greater	3	40001	16 bit registers

Exceptions (for reading Enron modbus data):

First Register	function code	minus offset	register size
32 (events)	3	0	32 bit registers
701 to 799 (history)	3	0	32 bit registers
1001 to 1999	1	0	1 bit coils
3001 to 3999	3	0	16 bit registers
5001 to 5999	3	0	32 bit registers
7001 to 7999	3	0	32 bit registers

Physical Connection

Before sending a message, the ethernet port needs to be physically connected to a network with Modbus servers.

Sending the Request

Press the SEND button. The program then monitors for incoming data and displays all bytes received in the Response indicator. The SEND button is greyed out until a connection is established with the Modbus Server (Slave device).

While receiving, the response time counts up with a progress bar.          

Receiving stops when the expected response bytes are received or the time reaches the fail in value entered.

The 'expected response bytes' indicator is calculated from the input settings.
The response timer stops when this many bytes are received. 

Troubleshooting

Check the IP Address and Port in the Modbus Server (Slave device) to make sure it matches the settings in the Master.

Reading the Response

The data bytes in the response are displayed in the bytes column of the response table.

Use the pull-down boxes in the first column to set the data type for each value. more info...
The copy down button sets all data types to match the setting for the first value.

          The bytes and words can be swapped by toggling the High/Low check boxes.

The bytes are re-processed immediately as the settings are changed and the results are shown in the fourth column.
Sending another request for a new response is not required for a recalculation.

A notes column is provided to enter labels for the values.

       Press the clear notes button to blank the whole notes column.

Data Log  

All bytes sent and received are added to the datalog with date/time stamps. 

       Displays a Save As.. Dialog Box to allow the log contents to be saved to a text file.

          Empties the log contents. 

Send Continuously

  Check this box to send back to back requests.

  The seconds between receiving a response and sending the next request

Statistics

  The seconds taken for the slave to respond to last message.
  The total number of message requests sent.
  The number of message with an incomplete or absent response

  The longest amount of seconds taken for a response (not including failed responses).
  The average amount of seconds taken for a response (not including failed responses).
 The shortest amount of seconds taken for a response (not including failed responses).
  Sets all statistical values back to zero. 

Save and Restore Configurations

          Displays a Save As.. Dialog Box to allow saving the current settings and results to a text file.

     Displays a Open File.. Dialog Box to allow selecting a previously saved settings file to load.

                ------------------------------------------------------------------------------------

Writing Data

        Displays the Simply Write Modbus TCP 1.3.6 window

Controls (inputs) that can be changed by the user are shown in yellow.
Indicators (outputs) shown in blue cannot be changed.

Set the controls to build the Command string.

The mode setting is copied from the previous window and can also be changed here.

            Select TCP or RTU-over-TCP mode.  more info... 

The IP Address and Port are copied from the previous window and cannot be changed here.

        The 7th byte in the Command string. in TCP Mode (The 1st byte in RTU-over-TCP mode)
                   The unit address of the Slave device to get data from.  normal range:  1 to 247 more info...

                  Setting a Slave ID over 255 will automatically check this box and allow Slave IDs up to 65535.   more info...
                              Remains on for all addresses until the Slave ID is lowered below 256 and the box manually unchecked.

        The 8th byte in the Command string. in TCP Mode (The 7th byte in RTU-over-TCP mode)
                    Can be automatically set  more info...
                    Used to select which table to write to.  more info...
                    Write Window supports Function codes 05, 06, 15 & 16

         The 9th & 10th bytes in the Command string. in TCP Mode (The 3rd & 4th bytes in RTU-over-TCP mode)
                           The coil or register number at the start of the block to be written.    more info...

                               This value is subtracted from the First Register to give the data address used in the Command.

     The 11th & 12th bytes in the Command string. in TCP Mode (The 5th & 6th bytes in RTU-over-TCP mode)
                          The quantity of registers or coils in the block to be written.

         Check to automatically set the default values for function code, offset and register size
                         when the value of First Register is changed.

                        The size of the registers in the block to be written.
                                                 This value should be set to 16 bit registers to write standard modbus registers.
                                                 and set to 1 bit coils to write standard modbus coils.
                                                 32 bit registers should be used for Enron modbus only. more info...

Auto Set values:

First Register	function code	minus offset	register size
1 to 7000	5	1	1 bit coils
7001 to 7999 (Enron modbus)	16	0	32 bit registers
8000 to 10000	5	1	1 bit coils
10001 to 30000	5	10001	1 bit coils
30001 to 40000	6	30001	16 bit registers
40001 & greater	6	40001	16 bit registers

Data to Write

The values to write are entered in the table shown.  The table size is automatically adjusted as the #values to write is changed.

     Use this pull-down box to set the data type for the whole table to be written.

         The bytes and words can be swapped by toggling the High/Low check boxes.

Sending the Command

Press the SEND button. The program then monitors for incoming data and displays all bytes received in the Response indicator.

While receiving, the response time counts up with a progress bar.          

Receiving stops when the expected response bytes are received or the time reaches the fail in value entered.

The 'expected response bytes' indicator is calculated from the input settings.
The response timer stops when this many bytes are received. 

Reading the Response

The data bytes in the response are displayed in the bytes column of the response table.

Data Log  

All bytes sent and received are added to the datalog with date/time stamps. 

       Displays a Save As.. Dialog Box to allow saving the log contents to a text file.

          Empties the log contents

Save and Restore Configurations

          Displays a Save As.. Dialog Box to allow saving the current settings to a text file.

     Displays an Open File.. Dialog Box to allow selecting a previously saved settings file to load.

Press the Close box in the top corner to Exit the Write program.

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