WinAC RTX 2008 Virtualization: Intel NIC Compatibility Guide

Overview: WinAC RTX 2008 Deployment Constraints

Siemens WinAC RTX 2008 is a software-based PLC (SoftPLC) that runs the S7-300/S7-400 instruction set on a Windows host augmented with the IntervalZero RTX real-time extension. The RTX subsystem provides a deterministic execution layer (typically a dedicated core isolated from the Windows scheduler) on which the WinAC PLC runtime executes the STEP 7 user program, OB, FB, FC, and DB blocks. WinAC RTX 2008 exposes both a Profinet IO Controller and a Profinet IO Device interface, and that interface is the central source of the deployment constraints described in this reference.

For Profinet IO, WinAC RTX 2008 binds directly to a physical Ethernet controller via the RTX network driver stack. The binding is not a soft binding to the Windows TCP/IP stack; it is a hard real-time binding that participates in the Profinet IRT/RT cycle. As a consequence, only a small set of Intel Ethernet controllers are qualified by Siemens for use with the RTX-based Profinet driver. The official qualification is documented in the Windows Automation Center RTX WinAC RTX 2008 manual.

The two devices that appear most often in field deployments and engineering discussions are the Intel 82541PI (older, PRO/1000 GT desktop family) and the Intel 82574L (PCIe Gigabit, used in Intel CT Desktop adapters). When a project requires virtualization, test benches, or portable commissioning laptops, the NIC dependency becomes a hard gating item.

Why WinAC RTX 2008 Cannot Use a Generic NIC

Profinet IO Controller / IO Device operation requires:

• Deterministic send/receive latency on the order of 1 ms for RT frames and sub-millisecond for IRT.
• Direct memory-mapped register access from real-time context (RTX HAL), bypassing the Windows NDIS stack.
• Known silicon behavior for time-stamping, PHY link-state handling, and interrupt moderation. Off-the-shelf Realtek, Broadcom, Killer, or Marvell NICs do not have a qualified RTX driver, and the RTX Profinet stack will not bind to them.

Hypervisor virtualization (VMware Workstation/ESXi, Hyper-V, VirtualBox) further abstracts the NIC. By default, a virtual machine presents an emulated adapter (VMware: E1000; Hyper-V: synthetic netvsc; VirtualBox: PCnet/Intel PRO/1000) whose driver model does not match the RTX Profinet driver surface. This is the root cause of the question that initiates this reference: Can WinAC RTX 2008 be used on a laptop with no Intel 82541PI, only an arbitrary or virtualized Ethernet controller?

Supported Intel NIC Family and PCI Identifiers

The two device IDs that have stable, qualified RTX Profinet drivers are summarized below. Field engineers should verify the exact subsystem vendor / device ID in Windows Device Manager before commissioning.

A supported NIC is required even for pure simulation use cases that still drive the Profinet stack, because WinAC RTX 2008 only loads its Profinet driver against a matching device. Without it, the Profinet IO Controller will not start and the diagnostic buffer will record entry 0xE001-class startup errors related to the communication initialization.

Three Realistic Options to Get WinAC RTX 2008 Running Off the Qualified Hardware

When the host does not have an Intel 82541PI or 82574L, the engineer has three working options. Each has a different cost / fidelity trade-off and is appropriate for a different part of the project lifecycle.

Option 1 - VMware E1000E Emulation of I82574L

VMware Workstation introduced the E1000E virtual NIC in virtual hardware version 8 and later. The E1000E emulation presents a device that reports the Intel 82574L PCI device ID (0x10D3) to the guest. WinAC RTX 2008 sees the qualified 82574L silicon and binds its Profinet driver. To use this path:

1. Set the VM to Hardware compatibility: Workstation 8.0 or newer (or ESXi 5.0+ equivalent). Older hardware versions only expose E1000, which does not match 82574L.
2. In VM settings, change the network adapter from E1000 to E1000E.
3. Confirm in the Windows guest Device Manager that the network adapter enumerates as Intel(R) 82574L Gigabit Network Connection.
4. Install the WinAC RTX 2008 software stack and select the E1000E-presented 82574L when the RTX Profinet driver setup asks for the network adapter.
5. Configure the RTX Profinet interface IP address and device name; verify that the RTX driver loads without diagnostic buffer entries.

This path keeps the project on a laptop. The trade-off is that Profinet IRT cycle accuracy depends on the host's ability to schedule the virtual NIC interrupt in time. RT frames work reliably in office/lab conditions; IRT cycle < 1 ms may not be deterministic and must be validated with a ProfiTrace on a real network.

Option 2 - WinAC IP Driver V2 (Windows TCP Stack Bypass)

Siemens ships an add-on called WinAC IP Driver V2 that lets the WinAC RTX runtime send and receive S7 communication over the standard Windows TCP/IP stack instead of the RTX-bound Profinet driver. The implications are non-trivial:

• The standard T-block library (FB63 TSEND, FB64 TRCV, FB65 TCON, FB66 TDISCON, UDT65 TCON_PAR, and the legacy AG_SEND/AG_RECV pairs) cannot be used unchanged. The driver ships a set of slightly modified T-blocks that call the IP Driver entry points instead.
• The modified T-blocks are not multi-instance capable. A given FB instance must be bound to one connection. Engineering must avoid call FBxxx, DB1 patterns where the same DB is re-used; each instance needs its own DB.
• No Profinet IO is available on this path. It is suitable for S7 communication (PUT/GET, ISO-on-TCP, TCP) to other controllers, HMI, and SCADA, but not for Profinet IO device or controller roles.

This option is the right answer when the goal is to test STEP 7 program logic, FB behavior, and S7 communication routing inside a virtualized Windows host, but it does not replace a real Profinet IO controller in production.

Option 3 - Native Deployment with a Supported Intel NIC

For office test benches and for any production cell, the recommended path is to install a real Intel 82541PI or 82574L PCIe/PCI card in the host PC. Field procurement notes:

• The Intel CT Desktop Adapter (EXPI9301CT) uses the 82574L and is widely available as new old stock for around €20-25. It is a PCIe x1 card, low profile, and works in most WinAC panel PCs.
• For older host PCs with only 32-bit PCI slots, an 82541PI-based PRO/1000 GT (PWLA8391GT) is the correct choice. Do not substitute an 82540EM-based PRO/1000 MT - the device ID differs and the RTX Profinet driver will not load.
• Disable all other NICs in Windows Device Manager and in BIOS so the RTX Profinet driver binds deterministically. Multiple active NICs can confuse the RTX NDIS miniport selection.

Native deployment is the only path that supports Profinet IRT with cycle times at or below 1 ms. It is also the only path officially described in the WinAC RTX 2008 manual for production duty.

PG/PC Interface Configuration for Loopback Testing

When STEP 7 and WinAC RTX 2008 are installed on the same host and no external Profinet device is required, the PG/PC Interface can be set to Internal. This makes the STEP 7 programmer talk to the WinAC RTX runtime over an in-host channel instead of over Ethernet. To configure this:

1. Open Control Panel > Set PG/PC Interface (or the modern SIMATIC Manager > Options > Set PG/PC Interface).
2. Select the access point S7ONLINE (STEP 7) -> Internal.
3. In the WinAC RTX 2008 Component Configuration editor, verify that the PLC slot is configured and that the connection target is the local RTX instance, not a remote CP.
4. Download the STEP 7 project; the runtime should reach RUN within a few seconds. Watch the diagnostic buffer for the typical startup sequence: Startup completed; Restart.

The Internal PG/PC interface is independent of the Intel NIC requirement. It is the cheapest way to validate that the STEP 7 program logic, OB scheduling, and FB behavior are correct, with no Profinet traffic at all.

PLCSIM as the Higher-Fidelity Alternative for Pure Logic Tests

For tests that do not require any Profinet IO and do not require a true hard-real-time WinAC PLC, S7-PLCSIM simulates an S7-300/S7-400 CPU in the STEP 7 / TIA Portal environment on the same PC. PLCSIM does not require a real Intel NIC, does not require RTX, and runs as a Windows process. It supports most of the S7 instruction set, including FBs, FCs, multi-instances, and most of the standard library. It does not simulate Profinet IO; for that, you need either an actual Profinet device or a Profinet IO simulator on a real network.

For projects that mix S7 logic testing with Profinet IO testing, the practical split is:

Profinet Communication Considerations in Virtualized Environments

Profinet differentiates between RT (real-time, switched Ethernet, ~1 ms cycle) and IRT (isochronous real-time, hardware-scheduled, sub-millisecond cycle). On a virtualized host, several behaviors must be understood before trusting test results:

• RT class 1 and unsynchronized RT work in a VMware guest with the E1000E adapter when the host has CPU pinning, reserved memory, and Hardware Version 8 or higher. Latency overhead vs. native is typically tens of microseconds.
• RT class 2 and IRT require cut-through switching and time-aware NIC behavior that is not fully preserved through the VMware virtual switch. Expect dropped IRT frames or late alarms when cycle times are pushed below 1 ms.
• The virtual switch introduces additional jitter. When the goal is to validate cycle-time budgets measured against the real plant network, use a physical Intel NIC on a dedicated WinAC panel PC, not a VM.
• Disable VMware features that relocate the guest memory or hot-migrate the VM (vMotion) when the WinAC RTX runtime is active. RTX schedules time-critical threads to specific cores; live migration will break the schedule.

Step-by-Step: Configuring VMware for WinAC RTX 2008 Compatibility

The following procedure yields a working WinAC RTX 2008 Profinet IO Controller on a laptop with no physical Intel 82574L. Use this for engineering test benches, FAT benches, and code reviews - not for production.

1. Install VMware Workstation 8.0 or later (or VMware Player with hardware compatibility 8.0+). ESXi 5.0+ also works.
2. Create a new Windows XP Professional x86 or Windows 7 Professional x86/x64 guest, depending on the WinAC RTX 2008 version's supported OS list in the manual. Allocate at least 2 vCPUs, 4 GB RAM, and 60 GB disk.
3. Set Virtual Machine Settings > Options > General > Version to Workstation 8.0 or newer. Older versions do not expose E1000E.
4. Set Network Adapter to Custom: VMnet0 (Bridged) - or - VMnet2 (Host-only), with the adapter type explicitly changed to E1000E. Do not use NAT if you intend to test Profinet against real devices.
5. In the guest, install VMware Tools, then open Device Manager. Confirm that the Ethernet adapter enumerates as Intel(R) 82574L Gigabit Network Connection. If it shows 82545EM, the adapter is E1000 - revert to step 3 and check the hardware version.
6. Install STEP 7 V5.4 SPx or V5.5 and WinAC RTX 2008 with all SP updates applicable to your license.
7. During WinAC RTX installation, when prompted for the network adapter for the Profinet driver, select the E1000E-presented 82574L.
8. Set the WinAC RTX component configuration to use a Profinet IO Controller; assign an IP address, station name, and device number consistent with your project.
9. Open the Set PG/PC Interface tool; for the S7ONLINE access point, choose the E1000E adapter or the Internal entry, depending on whether you target a remote PLC/HMI or the local WinAC instance.
10. Download the STEP 7 project to the WinAC RTX instance. Confirm the diagnostic buffer shows a clean startup and the Profinet IO Controller reaches RUN with the expected devices in IO controller / device list.

Verification Checklist

Diagnostic and Troubleshooting Matrix

Field-Commissioned Notes and Caveats

• Always validate any virtualization approach against the actual Profinet network that will run in production. A test bench that works in the office can fail in a plant with electrical noise, ground loops, or different switch infrastructure.
• The WinAC IP Driver V2 modified T-blocks are not multi-instance capable. Project templates must enforce one DB per connection. Lifting this constraint leads to SF (system fault) on the WinAC instance and cryptic errors in the diagnostic buffer.
• When the field environment demands a laptop, accept that Profinet IRT with cycle times below 1 ms is unlikely to be deterministic under VMware. The realistic target is RT class 1 at 1 ms or longer.
• For a permanent portable test bench, an external USB-to-Ethernet adapter cannot be substituted for the qualified Intel NIC. The RTX Profinet driver does not have USB-Ethernet support.
• Keep the WinAC RTX 2008 installation isolated from other STEP 7/TIA Portal versions on the same Windows host. Co-installation of multiple STEP 7 versions is a frequent source of PG/PC interface corruption and is outside the scope of this reference, but a clean host is the single largest source of reduced commissioning time.

Summary of the Working Options

Three approaches make WinAC RTX 2008 usable when the host does not ship with the required Intel 82541PI or 82574L:

1. Use VMware with E1000E (hardware version 8+) so the guest sees a virtual 82574L. The cheapest path that preserves Profinet IO controller capability, with the caveat that IRT below 1 ms is not guaranteed.
2. Use the WinAC IP Driver V2 and the modified T-blocks. The right answer when the goal is S7 communication (not Profinet IO) inside a virtualized or non-qualified host. Multi-instance FB calls are not allowed.
3. Install a real Intel 82541PI (PCI) or Intel 82574L (PCIe) Ethernet card in the host. The only path that supports Profinet IRT for production. Parts are inexpensive and widely available.

For pure STEP 7 program logic testing, the S7-PLCSIM simulator remains the right tool: no NIC requirement, no RTX, and no virtualization overhead. Choose the tool that matches the layer of the system under test.