Problem Description
When commissioning a mixed-vintage SIMATIC installation, engineers frequently attempt to wire a modern SIMATIC S7-1500 CPU (ET 200SP, CPU 1511, CPU 1515, CPU 1517, or CPU 1518) to a legacy SIMATIC TP-277 6-inch Touch Panel. TIA Portal (V13 SP1 and later) blocks the integrated HMI connection and returns the dialog message:
Symptomatically, the following observations are confirmed in the project tree:
- The S7-1500 CPU does not appear in the HMI connections → Communication drivers drop-down list when configured against a TP-277.
- The TIA Portal Connections editor refuses to bind the TP-277 to the S7-1500, but accepts binding to an S7-300 or S7-400.
- The integrated HMI wizard fails during automatic link generation, leaving a red exclamation mark on the connection node.
The TP-277 is functional, the S7-1500 is reachable on PROFINET, and there are no firewall or cabling issues — the failure is a configuration-level mismatch inside TIA Portal itself.
Affected Products and Versions
| Component | Catalog / Type | Firmware | Status |
|---|---|---|---|
| SIMATIC TP-277 6" Touch | 6AV6 643-0AA01-1AX0 (and -1AX1) | WinCC flexible 2008 / TIA HSP for TP-277 | Legacy HMI, no native S7-1500 driver |
| SIMATIC S7-1500 CPU | CPU 1511-1 PN through CPU 1518-4 PN/DP | Firmware V1.5 and later | Modern controller, only S7-1500-aware HMIs listed in integrated connection table |
| TIA Portal | V13, V13 SP1, V14, V14 SP1, V15, V15.1, V16, V17 | — | All versions reproduce the same restriction; HSP for TP-277 does not include S7-1500 device descriptor |
| STEP 7 (Classic) | V5.5 + SPx | — | Not the workaround path; S7-1500 is not editable in classic STEP 7 |
Root Cause Analysis
The TP-277's TIA Portal HMI device descriptor is a back-port from WinCC flexible 2008 SP2/SP3. The integrated HMI connection editor in TIA Portal matches HMI peers to PLC peers using a bidirectional capability table that maps the HMI's supported communication drivers to specific PLC families. The TP-277 device descriptor advertises only these PLC families:
- SIMATIC S7-300 / ET 200S
- SIMATIC S7-400 / ET 200pro
- SIMATIC S7-1200 (only with the dedicated V4 HSP for TP-277)
- SIMATIC LOGO! (8.FS4 onward)
- OPC server (channel)
The S7-1500 family is intentionally absent because the S7-1500's ISO-on-TCP / S7 communication path requires an S7-1500-aware OPC/PN stack that the TP-277's WinCC flexible runtime does not implement. TIA Portal enforces this matrix at compile time, which is why the binding is refused even when the network is otherwise healthy.
Why the S7-300/400 Driver Works
The S7-300/400 family uses the classic S7 communication protocol (port 102, ISO-on-TCP, TPKT/ISO transport) for PG/OP communication. The S7-1500 firmware has retained full backward compatibility with this legacy S7 protocol specifically to allow older HMIs, SCADA servers, and PG devices to keep functioning. The S7-1500 exposes a "compatibility slot" — Expansion Slot 1 in the TIA HMI connection editor — that mimics an S7-300 for the purpose of legacy OP communication. This is the technical reason the S7-300/400 driver with Expansion Slot 1 succeeds where the S7-1500 driver does not.
Resolution Overview
The accepted workaround, confirmed by Siemens in FAQ 109475049 and reproduced by Siemens Application Support, consists of four coordinated steps:
- Create the HMI–PLC connection manually on the TP-277 side, not on the PLC side.
- Select the S7-300/400 communication driver and bind it to Expansion Slot 1 of the S7-1500.
- On the S7-1500, enable Permit access with PUT/GET communication from remote partner in the CPU's protection properties.
- Ensure every data block consumed by the panel is configured as Non-optimized (classic DB), so the legacy OP can read absolute addresses.
After these four steps, the TP-277 communicates with the S7-1500 using legacy S7 protocol via the compatibility slot, with documented functional restrictions covered later in this article.
Step-by-Step Procedure
Step 1 — Open the TP-277 Connection Editor
In the TIA Portal project tree, expand Devices & Networks and select the TP-277 device. Open the Connections editor (right-click → Connections, or via the device's Connections tab). Right-click an empty row and choose Add new connection.
Step 2 — Select the S7-300/400 Driver
In the Communication driver column of the new connection row, choose S7-300/400 (the legacy entry, not the S7-1200/1500 entry). The dialog accepts this driver for an S7-1500 peer because of the compatibility-slot mechanism.
Step 3 — Bind to Expansion Slot 1
With the S7-300/400 driver selected, click the Partner (PLC) field and browse to the S7-1500 in the project. TIA Portal will display the S7-1500's slots; set the slot to Expansion Slot 1. This tells the legacy OP to talk to the S7-1500 as if it were an S7-300 with a backplane IM in slot 1.
Step 4 — Configure Network Parameters
In the connection's Properties → General dialog, set the following fields:
| Parameter | Value | Notes |
|---|---|---|
| Interface | PROFINET (PN/IE) | Only PN interface is supported on S7-1500 |
| IP address (PLC) | 192.168.0.1 (example) | Must match the CPU's PROFINET interface |
| IP address (HMI) | 192.168.0.10 (example) | Same subnet, no router hops for OP comms |
| Subnet mask | 255.255.255.0 | — |
| Connection name | Free text | Used in tag prefix on the HMI |
| Connection path | S7ONLINE → PN/IE | Required for runtime |
Step 5 — Enable PUT/GET on the S7-1500
Without this permission, the TP-277 cannot read or write tags, and runtime errors 1700001 / 1700004 appear on the panel.
- Select the S7-1500 CPU in the project tree.
- Open Properties → Protection & Security → Connection mechanisms.
- Tick Permit access with PUT/GET communication from remote partner (PLC, HMI, OPC, …).
- Compile and download the hardware configuration to the CPU.
Step 6 — Set Data Block Attributes to Non-Optimized
Optimized DBs (the S7-1500 default) use symbolic-only addressing and have no fixed offset table. Legacy OP communication via the S7-300/400 driver requires absolute byte offsets, so the panel cannot resolve tags pointing into optimized blocks.
For every DB the TP-277 reads or writes:
- Open the DB in TIA Portal.
- Right-click the DB header in the project tree → Properties → Attributes.
- Uncheck Optimized block access.
- Recompile the S7-1500 program; the download dialog will warn that all instances of the DB will be re-initialized to default values.
Verification Procedure
After configuration, validate the link from both ends.
Verification on the S7-1500
- Go online with the CPU (TIA Portal → Online → Go online).
- Open Diagnostics → Connection diagnostics or the Online & Diagnostics → Connections view.
- Confirm that an S7 connection from the TP-277's IP appears with state
ESTABLISHED. - On the panel, use the System → Network → Connection screen to view the active partner; it should display the S7-1500's IP and slot 1.
Verification on the TP-277 Runtime
- Transfer the compiled HMI project to the TP-277 (TIA Portal → Online → HMI Maintenance → Transfer).
- On the panel, enter Start Center → Settings → Transfer; the runtime should report the active S7 connection without error code 0x1700xxx.
- Toggle a bit in a non-optimized DB and verify the corresponding HMI tag updates within one refresh cycle (default 1 s for area pointers).
Functional Limitations
The S7-300/400 compatibility path is functional, not feature-parity. The following restrictions apply and are inherent to the protocol bridge:
| Capability | Native S7-1500 HMI | TP-277 via S7-300/400 Driver |
|---|---|---|
| Symbolic tag browsing | Yes | No (absolute addressing only) |
| Optimized DB access | Yes | No (must be non-optimized) |
| PUT/GET password protection | Yes (per connection) | No (password field ignored on the panel) |
| Secure PG/OP communication (TLS) | Yes (FW V2.6+) | No (plain ISO-on-TCP only) |
| Area pointers (date/time, job mailbox) | Yes | Yes (with manual pointer setup) |
| Alarms (bit-message, analog, S7 diagnostic) | Yes | Partial — diagnostic alarms unavailable |
| Maximum number of connections | Up to 128 (CPU-dependent) | Counts against the legacy S7 connection limit (typically 16) |
Recommended Migration Paths
For new machines, the S7-300/400 compatibility shim is acceptable only as a stopgap. Plan a panel replacement within one or two service cycles. Siemens currently ships the following TIA Portal-native panels that pair with the S7-1500 without the workaround:
- SIMATIC TP700 Comfort — 7" wide-screen, 16M colors, PROFINET, native S7-1500 driver.
- SIMATIC TP900 Comfort — 9" wide-screen, capacitive multi-touch (V2 firmware).
- SIMATIC TP1200 Comfort — 12" wide-screen, multi-touch, recommended for new cells.
- SIMATIC KTP400 / KTP700 / KTP900 / KTP1200 — Basic Panels (2nd generation) with S7-1500 native support on firmware V14 onward.
- SIMATIC HMI Unified Comfort (MTP700 / MTP1000 / MTP1200 / MTP1500 / MTP1900 / MTP2200) — newest generation, requires TIA V17+ and S7-1500 firmware V2.9+.
When replacing the TP-277, port the HMI project using TIA Portal's Migrate project function. WinCC flexible SP3 archives (.hmi) and earlier TIA V13/V14 archives can be migrated; the converter translates tags, screens, and alarms to the new panel and re-binds the connection to the native S7-1500 driver automatically.
Troubleshooting Matrix
| Observed Symptom | Likely Cause | Corrective Action |
|---|---|---|
| "Communication driver cannot be used with the HMI device" at compile time | TP-277 was added before the S7-1500 HSP; or driver auto-selected as S7-1500 | Force the connection to the S7-300/400 driver from the HMI-side editor |
Runtime error 1700001 on TP-277 |
PUT/GET not permitted on the CPU | Enable Permit access with PUT/GET in CPU protection properties; download config |
Runtime error 1700004 on TP-277 |
IP/subnet mismatch; wrong expansion slot | Verify IP, mask, and slot 1 binding; ping the CPU from a PG in the same subnet |
Tags show #### on the panel |
DB is optimized; no fixed offset | Set DB attribute Optimized block access = false; recompile and reload |
| Connection establishes but writes are ignored | HMI tag points to a read-only area (e.g. inputs) | Recreate the tag with correct direction; check DB variable's Accessible from HMI attribute |
| Random disconnects after 8–10 minutes | Connection watchdog mismatch; S7 keep-alive not aligned | Set Connection monitoring time in the S7-1500 ≥ 30 s; check for PN switch spanning-tree reconvergence |
| Compile error: "No S7-1500 driver available for TP-277" | TP-277 HSP missing or out of date | Update HSP for TP-277 via TIA Portal Options → Support Packages; restart TIA Portal |
| TP-277 boots but shows no PLC connection indicator | Project not transferred, or transfer mode enabled without project | Recompile HMI project; force transfer via Start Center → Settings → Transfer |
Network and Security Considerations
When forcing legacy S7 communication on a modern PROFINET plant network, segment the legacy HMI traffic from the rest of the cell. Recommended practices:
- Place the TP-277 in a dedicated VLAN with the S7-1500's PROFINET interface; do not share the VLAN with IT traffic.
- Disable routing of port 102/TCP (ISO-on-TCP) on the L3 boundary; limit to point-to-point reachability only.
- Enable the S7-1500's Access protection levels 1–3 to require a password for write operations, even with PUT/GET permitted. Read remains open by design of the legacy OP protocol.
- Document the TP-277 as a "legacy device requiring PUT/GET" in the network register; mark it for replacement in the next HMI refresh cycle.
Field-Commissioning Notes
When commissioning on-site, the following sequence reduces repeat visits:
- Pre-stage the project: S7-1500 program with all HMI DBs already marked non-optimized, panel project using the S7-300/400 driver with slot 1, PUT/GET pre-enabled in the offline hardware config.
- At the cabinet, first download the S7-1500 hardware config; confirm the protection flags have been applied by going online and re-reading Properties → Protection.
- Download the S7-1500 program; wait for the CPU to reach RUN.
- Power the TP-277, enable transfer, and transfer the HMI project.
- From the TP-277's System → Network screen, perform a ping to the S7-1500; this validates Layer 3 before S7 protocol testing.
- Open a screen with a known tag; verify the value tracks the PLC within one refresh cycle.
- Force a write from the panel back to the PLC and confirm the change in the PLC's online watch table.
Summary of the S7-1500 ↔ TP-277 Integration Pattern
- The TP-277 is technically a WinCC flexible-runtime panel and predates the S7-1500 family; TIA Portal's device descriptor for the TP-277 will never list the S7-1500 as a peer.
- Use the legacy S7-300/400 driver from the HMI-side connection editor, with the S7-1500's Expansion Slot 1 selected.
- Enable PUT/GET access on the S7-1500; otherwise the panel cannot read or write.
- Configure every HMI-relevant DB as non-optimized.
- Accept the limitations: no symbolic browsing, no secure TLS, no optimized blocks, no connection password.
- Plan the TP-277 for replacement with a TP700 Comfort, TP900 Comfort, TP1200 Comfort, KTP series (2nd gen), or Unified Comfort panel to restore full S7-1500 integration.
References (Siemens Official)
- Siemens FAQ 109475049 — Panels that can communicate with SIMATIC S7-1200 / S7-1500 in TIA Portal.
- Siemens Industry Online Support — TIA Portal manuals, S7-1500 system manual, TP-277 device manual.
FAQ
Why does TIA Portal refuse to bind an S7-1500 to a TP-277 in the integrated connection editor?
The TP-277's device descriptor predates the S7-1500 and advertises only S7-300/400, S7-1200, and LOGO! as peers. TIA Portal enforces this capability table at compile time, which produces the "Communication driver cannot be used with the HMI device" error. Use the S7-300/400 driver bound to Expansion Slot 1 instead.
Which slot number do I select on the S7-1500 when adding the HMI connection?
Select Expansion Slot 1. The S7-1500 exposes a backplane-equivalent slot for legacy OP communication, and slot 1 is the only one the S7-300/400 driver will accept for this compatibility path.
Do I need to enable PUT/GET on the S7-1500 for the TP-277 to work?
Yes. In the CPU's Properties → Protection & Security → Connection mechanisms, tick Permit access with PUT/GET communication from remote partner. Without this flag, the TP-277 cannot read or write any tag and runtime reports error 1700001.
Can the TP-277 read optimized data blocks on the S7-1500?
No. The legacy S7-300/400 driver resolves tags by absolute byte offset, which optimized DBs do not expose. Disable Optimized block access in the DB's properties for every DB the panel touches, then recompile and download.
Is there a firmware update for the TP-277 that adds S7-1500 support?
No. The TP-277 belongs to the older WinCC flexible runtime generation and its device descriptor is frozen. For native S7-1500 integration, replace the TP-277 with a TP700/TP900/TP1200 Comfort, a 2nd-generation KTP panel, or a Unified Comfort MTP series panel.