S7-1200 Firmware 4.0 CPU Compatibility with TIA Portal V12

Overview

Engineers commissioning a new SIMATIC S7-1200 PLC that ships with CPU firmware V4.0 must select the correct version of the TIA Portal engineering framework. The SIMATIC STEP 7 Professional V12 engineering software (order number 6ES7822-1AA02-0YA5) does not support the V4.0 generation of S7-1200 CPUs. The minimum compatible environment is TIA Portal V13. This technical reference documents the firmware-to-TIA Portal mapping, the project migration path from V12, the inability to flash older hardware from firmware 3.x to 4.0, the requirement on the matching WinCC Advanced version for HMI tag integration, and the support status of the CP 1242-7 GPRS modem and the CB 1241 RS485 communications board on the new generation of S7-1200 controllers.

Siemens published a formal support note confirming the V12 limitation and the TIA Portal V13 trial availability for engineers evaluating the upgrade. The V13 SP1 release introduced forward project compatibility that allows V13 base projects to load directly in V13 SP2 without re-saving, and SP1 projects load directly in SP2 with no additional license cost for the conversion, which simplifies multi-engineer workflows where team members may be on incremental service packs.

S7-1200 CPU Generation and Firmware Map

The S7-1200 platform has been shipped in two hardware generations identified by the firmware major version and the catalog order number. The order number encodes the firmware release as part of the product version block (digit positions 11 and 12 of the MLFB). Engineers should always verify the printed part number on the CPU front flap and the firmware version reported by the online diagnostic buffer before assuming compatibility.

The two generations share the same I/O footprint and signal terminal layout, but the V4.0 generation is a distinct hardware revision. Functional changes include an expanded web server with user administration, additional PROFINET IO controller diagnostics, the extended _getTimeOfDay system API, integrated trace recording on the CPU, motion control extensions, and improved security (know-how protection per block, copy protection binding to the SIMATIC memory card). Siemens has explicitly stated that an update of already delivered SIMATIC S7-1200 controllers (CPU 1211C, CPU 1212C, CPU 1214C, and CPU 1215C) of the previous generation to the new CPU firmware V4.0 is not possible. This is not a license or firmware-blob restriction; the V4.0 firmware is built for the new hardware revision and will not execute on V3.0 silicon.

Verifying the CPU Generation in the Field

1. Power the CPU and connect the engineering PC to the PROFINET port (X1).
2. Open Online > Accessible Devices in TIA Portal.
3. Read the Order Number field. A V4.0 CPU is identified by the 40 in the product version block (e.g., 6ES7214-1AG40-0XB0).
4. Cross-check the Firmware field in the Online & Diagnostics view. V4.0 hardware reports firmware V4.0.x or later.
5. Confirm both values match the V4.0 catalog before proceeding with the V13 project.

TIA Portal V12 vs V13 Firmware Support Matrix

Each TIA Portal major version embeds the device descriptions (HSP — Hardware Support Packages) for the S7-1200 generation released up to that point. V12 was released in 2013 and ships with HSP updates covering the S7-1200 V3.0 product family. The V4.0 product family was released later, and the corresponding HSP was bundled with TIA Portal V13. As a result, V12 cannot enumerate, configure, or download to a V4.0 CPU.

The trial license for TIA Portal V13 and V13 SP1 is available from the Siemens Industry Online Support portal. Engineers evaluating the migration can download the trial to validate project conversion before purchasing the full license:

• SIMATIC STEP 7 (TIA Portal) V13 TRIAL Download
• SIMATIC STEP 7 (TIA Portal) V13 SP1 TRIAL Download

Per the Siemens support note for the V13 SP1 trial, projects authored in TIA Portal V13 can be used directly in TIA Portal V13 SP2 without any upgrade step. There are no additional license costs for converting from TIA Portal V13 to V13 SP1. This means an engineering team that standardizes on the V13 branch can adopt SP1 or SP2 incrementally without rewriting the project.

Why V12 Cannot Load V4.0 Projects

The TIA Portal project file (.ap12 for V12, .ap13 for V13, .ap13_1 for V13 SP1) embeds a schema version that records the TIA Portal release used to author the project. When a V12 project containing V3.0 hardware is opened in V13, the migration wizard inspects each device, validates its hardware catalog key, and rebuilds the device view against the V13 hardware catalog. If the project only references V3.0 hardware, the migration is lossless and all program blocks, tag tables, watch tables, recipes, and HMI connections are preserved.

Attempting to open a V13 project in V12 — or to download a V13 project to a V3.0 CPU — is blocked because the schema version is forward-only. The V12 compiler does not understand the V4.0 system constants (such as the expanded _getTimeOfDay API, the new web server user management, the integrated trace, or the expanded PROFINET diagnostics blocks) and will refuse to build. Engineers must keep the engineering environment on the highest major version present in the fleet.

Project Upgrade Path: V12 to V13 (and SP1/SP2)

Siemens has documented that TIA Portal V13 SP1 projects can be used directly in TIA Portal V13 SP2 without any upgrade, and there are no additional license costs for converting from TIA Portal V13 to V13 SP1. The same forward-compatibility policy applies in patches within the V13 branch. The migration rules are:

• V12 → V13: Open the .ap12 project. The V13 migration wizard prompts to upgrade. Save as .ap13. The V12 source file is not modified, so a rollback is possible.
• V13 → V13 SP1: Open the .ap13 project directly in V13 SP1. No explicit upgrade step is required. Optionally save as .ap13_1 if the team standardizes on the SP1 file extension.
• V13 SP1 → V13 SP2: Open the .ap13_1 project in V13 SP2. SP2 loads it without conversion or re-license.

For S7-1200 V3.0 projects migrated from V12 to V13, the CPU type, the user program in OB1/FB/FC, the DB layouts, the HMI tags, and the recipe data are preserved. The HMI device in the project (e.g., a KTP700 Basic PN or a TP900 Comfort) is re-resolved against the V13 HMI catalog. If the panel was added with a V12-only HSP, the migration will replace the catalog key with the equivalent V13 key. Connections to the PLC are restored automatically because the connection endpoint IP and slot are independent of the engineering version.

Migration Step-by-Step

1. Back up the .ap12 project file and any referenced libraries (*.al12) to a safe location.
2. Launch TIA Portal V13. Select Open Existing Project and navigate to the .ap12 file.
3. When prompted Do you want to upgrade the project?, click Upgrade. The wizard inspects every device and library reference.
4. Review the migration report. Any device that requires manual catalog key replacement is flagged with a warning.
5. Resolve flagged devices by selecting the equivalent V13 catalog type. The configuration (slots, addresses, comments) is carried over automatically.
6. Save the project as .ap13. The original .ap12 file remains on disk for rollback.
7. Compile the project (Project tree > CPU > Compile > All) and address any compile errors introduced by V13 catalog changes.

Firmware 3.0 to 4.0: Hardware vs Software Update

Engineers often ask whether an existing V3.0 CPU can be flashed to V4.0 to gain the new features. Siemens has explicitly answered this question in the product support database: the V4.0 firmware is targeted at the V4.0 hardware revision, and an update of already delivered SIMATIC S7-1200 controllers (CPU 1211C, CPU 1212C, CPU 1214C, CPU 1215C) of the previous generation to the new CPU firmware V4.0 is not possible. The CPU must be replaced with a V4.0 catalog number. There is no license key, firmware file, or SIMATIC memory card procedure that will change the outcome — the V3.0 bootloader rejects the V4.0 image because the hardware ID does not match.

New V4.0 Features Exposed Only in TIA Portal V13

The V4.0 CPU generation and the V13 engineering toolchain jointly expose a set of features that are not available on V3.0/V12 combinations. Engineers migrating a V3.0 program to a V4.0 CPU will gain access to:

None of these features are mandatory. A V13 project compiled for a V3.0 CPU and then redeployed to a V4.0 CPU (with the V3.0 CPU removed from the device tree) will run unchanged. The V4.0 features are available for engineers who choose to use them; the migration path does not force code changes.

WinCC Advanced Compatibility

For HMIs programmed with SIMATIC WinCC Advanced V12 (order number 6AV2102-0AA02-0AA5), the HMI runtime project is largely independent of the PLC firmware. WinCC Advanced V12 will compile and download a Comfort Panel or KTP project that connects to a V3.0 PLC. When the same WinCC Advanced V12 project is targeted at a V4.0 PLC, the HMI compile does not fail, but the tag browser cannot resolve V4.0-only PLC system constants introduced after V12. Two paths are available:

1. Stay on WinCC Advanced V12: Use only standard V3.0-compatible tag addresses. HMI integration with V4.0 PLCs works for user-defined DBs and the legacy system clock. The new web server user-management symbols and the extended _getTimeOfDay API are not exposed to the HMI tag list.
2. Upgrade to WinCC Advanced V13 or later: The V13 WinCC catalog recognizes the V4.0 PLC system constants and the expanded diagnostic block set. This is the recommended path for new deployments and for any site that wants full HMI visibility into the V4.0 trace and diagnostic features.

Siemens recommends running the HMI engineering and the PLC engineering on the same TIA Portal major version to ensure that the integrated project tree resolves all device references consistently. Side-by-side installation of V12 and V13 is supported on the same engineering PC, allowing a phased migration. The HMI connection — a PROFINET or MPI/PROFIBUS relationship between the panel and the PLC — is preserved across the engineering upgrade; the engineer does not need to re-establish the connection in the V13 project.

Communication Module Compatibility Matrix

Two communication modules are commonly added to an S7-1200 system: the CP 1242-7 GPRS modem for telecontrol and the CB 1241 RS485 communication board for freeport / Modbus RTU message-based communication. Both have been qualified for use with the S7-1200 firmware V4.0 CPU family.

For the CB 1241 RS485 with the message-based freeport protocol, the configuration is performed in TIA Portal under Device Configuration > CB 1241 > Properties > Port Configuration. The send/receive POU blocks (Send_P2P, Receive_P2P, Receive_Reset, Send_Config) are part of the STEP 7 instruction library and are available in TIA Portal V13 without additional installation. The V4.0 CPU does not require a different instruction set for freeport operation; the existing PtP program blocks load and execute unchanged from a V3.0 project.

For the CP 1242-7 GPRS, the telecontrol configuration is performed through the CP's own web-based management or via TIA Portal under the CP device properties. The CP firmware is independent of the CPU firmware and continues to be updated through the CP's own web interface or via the SIMATIC Automation Tool. The telecontrol protocol stack (IEC 60870-5-104 or DNP3) is loaded into the CP, not the CPU, and the PLC program interacts with the CP via the TMAIL_C instruction or the telecontrol library blocks.

Recommended Upgrade Workflow

For a site transitioning from V3.0 to V4.0 CPUs, the following sequenced workflow minimizes downtime and engineering risk.

1. Inventory the existing fleet. Build a spreadsheet of every S7-1200 CPU by order number, firmware version, and installed HSP. Identify the V3.0 units that will be replaced.
2. Order V4.0 replacement CPUs. Use the V4.0 catalog numbers (the 40 product version block, e.g., 6ES7214-1AG40-0XB0). Do not order V3.0 spares for long-term stocking.
3. Upgrade the engineering station. Install TIA Portal V13 (or V13 SP1 / V13 SP2) on each PC that will be used for the migration. The trial download is available from Siemens Industry Online Support.
4. Migrate the project. Open the existing V12 project in V13. Run the migration wizard. Verify that the project compiles cleanly. Resolve any device catalog key replacements that the migration tool flags.
5. Add the V4.0 CPU to the device tree. Insert a new CPU of the V4.0 catalog type. Copy the user program blocks, DBs, and tag tables from the V3.0 CPU instance. Remove the V3.0 CPU from the project.
6. Upgrade the HMI engineering. If WinCC Advanced V12 is installed, decide whether to keep it (standard tags only) or upgrade to V13 for full V4.0 PLC system constant access.
7. Compile and download the upgraded project. Compile the entire project (PLC + HMI). Download to the new V4.0 CPU and to the HMI panel.
8. Verify online. Use Online & Diagnostics > Compare to verify that the offline project matches the online program in the new CPU. Run the user program in RUN and confirm that the I/O scan is healthy.

Verification and Commissioning Checklist

After the migration, the following checks confirm that the V4.0 CPU is operating correctly with the V13 project and that the HMI link is healthy.

Troubleshooting Matrix

FAQ