Creating GSD Files in COM PROFIBUS 3.3 for ET 200 Devices

Overview

COM PROFIBUS 3.3 is a Siemens configuration utility used to design PROFIBUS DP and PROFIBUS FMS networks. It is the predecessor of STEP 7 hardware configuration (HW Config) for DP master and DP slave definitions. The companion tool COM ET 200 (COMET200) is used to configure the ET 200 distributed I/O family where the resulting project carries device master data in the legacy *.200 format rather than the standardized *.gsd text file. When a customer supplies an ET 200 project in *.200 format, engineers frequently need to regenerate or convert the device master data so a third-party PROFIBUS configuration tool can read it. This article documents the exact procedure, the directory layout, the supported identifier formats, and the limitations of COM PROFIBUS 3.3 on modern Windows hosts.

COM PROFIBUS is still listed in the PROFIBUS Product Finder as a configuring tool for DP/FMS projects. Version 5.0 was the last released build and runs under Windows 95/98 and Windows NT 4.0. Version 3.3 is the build that handles ET 200 *.200 imports and was the standard on Windows 95/NT installations of the late 1990s.

Prerequisites

1. COM PROFIBUS 3.3 installed on a Windows 95, Windows 98, Windows NT 4.0, or Windows 2000 host. Newer Windows versions can run the executable in compatibility mode but the GSD importer expects 8.3 file paths.
2. The full project tree produced by COM ET 200 (files with extension *.200, *.2bf, and the station description *.ets or *.etp).
3. Write access to the ...\PROGDAT directory where COM PROFIBUS 3.3 stores newly created device master files.
4. Text editor (Wordpad is the documented choice, since the GSD file is plain ASCII text). Do not use Notepad or rich-text editors that inject formatting characters.
5. For verification, a GSD syntax checker such as the PROFIBUS Nutzerorganisation GSD Checker, or the integrated COM PROFIBUS syntax check.

GSD File Format Background: *.gsd vs *.200

The PROFIBUS device master file is defined in IEC 61784 and the PROFIBUS Profile Guidelines. Two distinct encoding schemes appeared historically:

The *.200 extension indicates an ET 200 station description generated by COM ET 200. It is not directly consumable by third-party PROFIBUS tools. The conversion path is to import the project into COM PROFIBUS 3.3 and then export the device master file in standardized *.gsd form.

COM PROFIBUS 3.3 vs COM ET 200 (COMET200)

When COM PROFIBUS 3.3 opens a project containing a *.200 file, the contents are presented as a DP slave under a "dummy" master. The slave's module list, parameterization, and identifier format are retained from the COM ET 200 source. The Create GSD File and Create Device Master File functions then operate on that imported slave.

Step-by-Step: Importing a COM ET 200 Project and Creating a *.gsd File

The following procedure regenerates a missing *.gsd device master file from a customer's COM ET 200 project. The same flow applies when a third-party configurator needs the GSD to recognize the ET 200 slave.

1. Launch COM PROFIBUS 3.3 from the Start menu or from C:\Siemens\COMPROF\ComProf.exe.
2. Choose File > Open (or ALT, F, O). Navigate to the directory containing the customer's *.200 and *.2bf files. Select the *.2bf project file (the *.200 is referenced by the project).
3. COM PROFIBUS 3.3 loads the project and displays the imported ET 200 station as a DP slave under a "dummy" DP master. The DP master system window title reads DP master system PROFIBUS address X where X is the default address (typically 1 or 2).
4. Click the imported slave to select it. Verify the module list on the right pane matches the customer's documentation. The station type (compact or modular) is shown in the slave properties.
5. Choose File > Create device master file (or ALT, F, C). The same command is available in the right-click context menu of the selected slave.
6. The Create device master file dialog appears. Set the following parameters:
   • Device name - the manufacturer-assigned name to embed in the GSD header (e.g., ET200S, ET200M, ET200B).
   • Identifier format - select Compact PNO, Modular PNO, or Modular with slot list. Compact produces a single identifier byte; modular produces one per slot. Slot list is required for hot-swap configurations.
   • Modularity - matches the identifier format. The dialog rejects inconsistent combinations.
7. Click OK. The Save as dialog opens. Enter the file name with the .gsd extension and the directory (defaults to ...\PROGDAT).
8. COM PROFIBUS writes the GSD file to disk. The output is a plain ASCII file conforming to the GSD specification revision supported by COM PROFIBUS 3.3 (GSD Rev. 3, with limited Rev. 4 keywords).
9. Copy the new *.gsd to the GSD directory of the third-party PROFIBUS configuration tool (for STEP 7: ...\Step7\S7data\GSD; for TIA Portal: import via Options > Manage GSD files).
10. Restart the third-party configurator and add the new DP slave to the DP master system. Assign the PROFIBUS address originally used by the customer.

Step-by-Step: Creating a Device Master File from Scratch (No Source Project)

When the customer's project is not available but the DP slave hardware still exists, the device master file can be built by configuring a dummy DP slave and exporting:

1. Choose File > New (ALT, F, N). The Master host selection dialog opens. Select the default master station type and confirm with OK.
2. The DP master system PROFIBUS address X window appears with a "dummy" master.
3. Add a new DP slave to the master system. Configure the modules, slots, and parameters to match the target ET 200 station (refer to the hardware manual for the station type and supported modules).
4. Select the configured slave. Right-click and choose Create device master file from the pop-up menu.
5. In the dialog, enter the device name, identifier format, and modularity. Click OK.
6. Save the file with the .gsd extension to the ...\PROGDAT directory.
7. Copy the .gsd to the target configuration tool's GSD directory.

Step-by-Step: Converting *.gsd Back to *.200 (COM ET 200 Compatibility)

To produce a *.200 file from a project for use with COM ET 200:

1. Open the *.2bf project in COM PROFIBUS 3.3.
2. Choose File > Save as. In the file type selector, pick ET 200 project (*.200) from the legacy format list.
3. COM PROFIBUS writes a binary *.200 file that COM ET 200 (COMET200) can open. The structure is ET 200 family specific; only compact ET 200 station types are supported.
4. Launch COMET200 and open the regenerated *.200 to confirm the module list and parameterization are preserved.

GSD File Editing and Syntax Verification

Because GSD is plain ASCII, it can be opened and edited in Wordpad. Common edits include:

• Changing the Vendor_Name and Model_Name keywords in the GSD header.
• Adding User_Prm_Data definitions for non-default parameterization.
• Modifying Max_Diag_Data_Len if a third-party master imposes a smaller limit.
• Appending Module stanzas for I/O modules not present in the original configuration.

After any manual edit, run the GSD Syntax Check. In COM PROFIBUS 3.3, the check is invoked via Options > GSD syntax check. External tools such as the PROFIBUS GSD Checker from the PROFIBUS Nutzerorganisation provide a stricter validation against the GSD specification and must be used for GSD Rev. 4 and Rev. 5 conformance.

Troubleshooting Matrix

Verification

1. Open the generated *.gsd in Wordpad. Confirm the GSD_Revision, Vendor_Name, Model_Name, Ident_Number, and Module stanzas are present and match the target hardware.
2. Run the COM PROFIBUS 3.3 GSD syntax check (Options > GSD syntax check) and confirm no errors.
3. Copy the *.gsd to the third-party tool's GSD directory and add the slave to a test master system. The slave should appear in the catalog without error indicators.
4. Download the master configuration to a real DP master (Siemens S7, ABB, or other) and confirm the ET 200 slave enters data exchange (DX) state. Check the diagnostic buffer for any parameterization errors.
5. Re-export the configuration to verify the configuration tool can re-read the *.gsd without warnings.

Field-Proven Caveats

• COM PROFIBUS 3.3 cannot open projects created with COM PROFIBUS 5.0. The version direction is one-way: 3.3 is required for ET 200 *.200 legacy support, 5.0 is required for newer GSD Rev. 4 features. Keep both installed in separate directories.
• The ...\PROGDAT path is hard-coded. On a Windows host with a non-C: system drive, the path resolves to the installation drive's root PROGDAT. Confirm the actual output location by checking the File > Save as default.
• When exporting for a non-Siemens master, set the identifier format to "Compact PNO" unless the third-party master explicitly supports modular ET 200 stations. Several legacy masters reject the modular identifier byte encoding.
• The *.200 file does not embed PROFIBUS bus parameters. The bus parameters (baud rate, Tslot, Tset, etc.) are defined in the master configuration and are independent of the slave GSD.
• If the customer's project contains proprietary parameterization that COM PROFIBUS 3.3 cannot parse, the imported slave will appear with default parameters. The user must manually re-enter the parameterization before exporting the GSD; otherwise the regenerated GSD will overwrite the customer's settings.

FAQ