Resolving Driver Generator Error 'Not Interconnected or Connected to an Invalid Address' on Analog Signals in PCS 7

In SIMATIC PCS 7, the CFC compiler error 'Not interconnected or connected to an invalid address' during module driver generation occurs when an analog input channel driver (such as Pcs7AnIn) references an unreleased hardware module MLFB, an address outside the configured process image, or direct peripheral addressing (PIW) instead of Process Image Partition addressing (IW). To resolve this, configure HW Config using the 'PCS7_Vxx' catalog profile to ensure only certified modules are selected, assign module I/O addresses to a defined Process Image Partition (PIP), map the PIP to the cyclic interrupt OB executing the driver, and reference symbolic IW addresses.

Root Causes of Module Driver Compilation Failures

During the compilation of Continuous Function Charts (CFC) in SIMATIC PCS 7 with Generate module drivers enabled, the compiler inspects every channel driver block (Pcs7AnIn, Pcs7DiIn, etc.) and automatically creates upstream diagnostic blocks (MOD_D1, RACK, OB_DIAG).

A frequent and frustrating compilation error reports:

E: Chart 'Area/AI_Ch01' \ Block 'Pcs7AnIn' \ Pin 'PV_In': 
Not interconnected or connected to an invalid address.
Module driver generation aborted.

This error halts compilation and prevents target AS downloading. It is caused by three underlying engineering errors:
1. Unreleased Hardware Module: The physical module selected in HW Config (e.g., an older SM 331 6ES7331-1KF01-0AB0) is not certified for your PCS 7 library version, which requires 6ES7331-1KF02-0AB0. The driver generator has no XML module descriptor for the unreleased MLFB.
2. Direct Peripheral Addressing (PIW): Connecting channel drivers to raw peripheral addresses (PIW512) rather than process image inputs (IW512).
3. Process Image Overflow: The module address lies beyond the CPU's configured process image boundary and is not assigned to a valid Process Image Partition (PIP).

The Role of HW Config Catalog Profiles (PCS7_Vxx vs Standard)

In STEP 7 Hardware Configuration (HW Config), the hardware catalog on the right side of the screen can be filtered using Catalog Profiles:

The 'Standard' Profile Trap

If the catalog profile is set to Standard, the catalog displays every module ever manufactured by Siemens for S7-300, S7-400, and ET 200, including commercial automation cards that lack PCS 7 diagnostic driver support. Engineers accidentally drag older or unsupported modules into the station.

The 'PCS7_Vxx' Profile

When set to PCS7_V81 (or your active PCS 7 version), HW Config strictly filters the catalog to display only officially released modules that possess certified driver generator rules and diagnostic faceplates. If a module cannot be found under the PCS7_Vxx profile, it is not supported for automatic driver generation.

Comparison Table - Hardware Addressing Modes in PCS 7

The following table compares addressing conventions and their compatibility with PCS 7 automatic driver generation.

Addressing ModeExample SyntaxSupported by Driver Generator?Cycle TimingTypical ApplicationProcess Image Partition (PIP)IW 512 (in PIP 1)Yes (Standard)Synchronized with cyclic interrupt OBStandard PCS 7 APL process controlOB1 Process ImageIW 512 (in PIP 0)YesSynchronized with OB1 cycleNon-critical background signalsDirect Peripheral AddressPIW 512No (Triggers Compiler Error)Acyclic immediate readSpecial high-speed counters / MotionSymbolic Name BindingTI101_InputYes (Best Practice)Defined by underlying PIP assignmentAll APL channel driver interconnections

Step-by-Step Resolution and Driver Generation Procedure

Follow this verified engineering procedure to resolve the driver generation error:

Switch HW Config to the PCS 7 Profile:
* Open the target AS in HW Config.
* In the right-hand catalog window, locate the Profile dropdown menu.
* Change the profile from Standard to PCS7_V8.1 (or your current PCS 7 release).
Verify and Replace Unreleased Modules:
* Inspect the remote I/O station (e.g., ET 200M).
* Verify that every inserted module matches the released MLFB. For example, replace obsolete 6ES7331-1KF01-0AB0 with the certified 6ES7331-1KF02-0AB0.
* Save and compile HW Config.
Assign I/O Addresses to Process Image Partitions (PIPs):
* Double-click the analog input module in HW Config.
* Under the Addresses tab, note the start address (e.g., 512).
* In the Process Image dropdown, change OB1-PA to an explicit partition, such as PIP 1 (mapped to OB35 - 100 ms).
* Save and compile HW Config. Download HW Config to the CPU.
Assign Symbolic Names in the Symbol Table:
* Open the Symbol Table in SIMATIC Manager.
* Define a clear symbolic tag name for the address (e.g., TI101_PV = IW 512, Data Type WORD).
* Ensure the address uses IW, never PIW.
Reconnect Channel Driver in CFC:
* Open the CFC chart containing Pcs7AnIn.
* Disconnect any raw PIW string from input pin PV_In.
* Select PV_In and type the symbolic name TI101_PV (or address IW 512).
* Confirm that the interconnection displays as an orange signal bar.
Recompile CFC with Driver Generation:
* Execute Chart -> Compile -> Charts as Program.
* Select Scope: Changes only (or Entire Program if addresses changed significantly).
* Ensure Generate module drivers is checked.
* The compiler will generate the diagnostic blocks without errors.

Verification

Confirm that the module driver has generated cleanly:

Inspect Compilation Log:
* Open the CFC compile log (Options -> Logs -> Compile).
* Confirm that the log reports zero errors and zero driver generator warnings.
Inspect Generated Diagnostic Charts:
* In CFC, open the system-generated chart folder (typically named @...).
* Open the generated diagnostic chart for the module.
* Confirm that MOD_D1 (or MOD_HA) is instantiated and interconnected to your Pcs7AnIn block via the DXchg structure.
Verify Online Process Value:
* Download changes to the CPU in RUN mode.
* Place Pcs7AnIn in Test Mode. Confirm that PV_Out.Value displays live scaled data and Bad.Value = 0.

Limitations and Operational Precautions

Unreleased Third-Party Modules: If using third-party PROFIBUS DP or PROFINET devices via generic GSD files, the PCS 7 driver generator cannot create native module drivers. You must use generic driver blocks (FbDrive, FbEnDat) or write custom diagnostic evaluation logic.
Avoid Address Overlapping: Ensure that module input addresses do not overlap with other modules or internal bit memory (M) ranges.
CPU Process Image Sizing: In older S7-400 CPUs, ensure the assigned module address does not exceed the total configured process image size in CPU Cycle/Clock Memory properties.

Engineer FAQ

Why does PCS 7 prohibit the use of PIW on channel drivers?

Direct peripheral reads (PIW) bypass the CPU operating system's synchronized Process Image Partitions. PCS 7 driver blocks require PIP addressing (IW) to guarantee deterministic signal updates synchronized with the execution cycle of the cyclic interrupt OB.

Where can I find the official list of released PCS 7 modules?

Siemens publishes the 'SIMATIC PCS 7 - Released Modules' manual on SIOS for every release (Entry ID 109780813), detailing exact MLFBs and firmware requirements.

Can I compile module drivers for digital modules the same way?

Yes. Digital input and output channel drivers (Pcs7DiIn, Pcs7DoOut) follow identical rules, requiring symbolic IW/QW addressing assigned to PIPs.

What happens if I disable 'Generate module drivers' during compilation?

The CFC program compiles, but no diagnostic blocks (MOD_D1, RACK) are created. Channel drivers will lose hardware fault detection, wire break monitoring, and Maintenance Station faceplates will be blank.