When the C-More is meant to communicate with an Allen-Bradley PLC as an HMI, select an Allen-Bradley EtherNet/IP Client driver; the start-address prompt belongs to the Generic I/O Server driver.
Stop choosing the Generic I/O Server just to reach a PLC
The quickest wrong fix is to fill in the start address because the setup screen asks for one. That selects the wrong communication role when the C-More is supposed to initiate communication with an AB PLC. The Generic I/O Server is for making the C-More a server node on the EtherNet/IP network, not for using the panel as an ordinary PLC client.
- Do not guess a starting address. A value entered in a server-driver setup does not convert it into a client connection.
- Do not select a client driver just because the PLC is called a “slave.” Informal role names do not identify which driver the application needs. Decide which device initiates the connection and what data exchange the project requires.
- Do not buy a protocol converter as the first response. A converter may be an option when the needed device or protocol is unsupported, but first check whether the C-More has a client driver for the actual AB target.
For a typical HMI-to-PLC connection, configure the C-More as the client and the AB device as the target. Use the Generic I/O Server only when the design specifically requires the C-More to act as a server and exchange mapped I/O data.
Identify whether the C-More must be a client or server
“EtherNet/IP” alone does not tell you which driver to choose. Client and server describe different communication roles. In the client case, the panel initiates communication with a PLC using that PLC’s supported driver. In the generic server case, the panel is the EtherNet/IP server node and participates in I/O mapping configured for the network.
| Project intent | Driver direction | What the setup asks you to do |
|---|---|---|
| Use the panel as an HMI to communicate with an AB PLC | Allen-Bradley EtherNet/IP Client, selected for the target device | Enter the target device’s IP address; a generic server start address is not the client setup. |
| Make the C-More a slave/server node for mapped I/O | Allen-Bradley EtherNet/IP Server (Generic I/O Messaging) (Control/CompactLogix) | Configure the required start address and I/O mapping for the intended arrangement. |
The term “slave” in a project description is not enough to decide. Ask whether the PLC is expected to initiate an I/O connection to the C-More, or whether the C-More is expected to initiate data access to the PLC. That answer determines the driver path.
Use the driver prompt to diagnose the mismatch
A start-address prompt is a useful clue: it indicates that the selected driver is the Generic I/O Server path described here, not one of the EtherNet/IP Client drivers. It does not, by itself, identify a valid start address or prove that the intended PLC supports the requested arrangement.
| Symptom | Likely selection issue | Next check |
|---|---|---|
| The setup asks for a starting address, but the goal is to connect the HMI to a PLC. | Generic I/O Server selected instead of an EtherNet/IP Client. | Return to driver selection and identify the AB device model/family. |
| The application needs I/O mapping and treats the C-More as a network node. | Client driver may not match the required server role. | Confirm the Generic I/O Server is intended and determine the matching I/O map from the project and product documentation. |
| A client driver is selected, but the device is not communicating. | Wrong client variant, wrong target IP address, or network/application configuration issue. | Verify the driver selection against the actual AB target, then check IP reachability and configured data access. |
Do not try to solve a driver-role mismatch by changing PLC addresses or entering arbitrary I/O offsets. First establish the target device and connection model; then configure addresses using the documentation for that specific driver and project.
Configure an EtherNet/IP Client for ordinary PLC access
- Identify the exact AB device the panel must communicate with. Do not choose a driver based only on the manufacturer name.
- In the C-More project, select the matching Allen-Bradley EtherNet/IP Client driver. The documented choices include three client variants; the correct one depends on the target device.
- For an SLC 5/05, the example client choice is “SLC5/05/ENI Adapter.” Select it only when that is the actual target type.
- Enter the IP address of the device being communicated with. Do not substitute the panel’s own address.
- Configure the HMI data references according to the selected driver’s addressing rules and the PLC project. Check the installed C-More documentation for the exact syntax and supported data types; do not infer those from the server start-address field.
Client drivers do not imply Generic I/O messaging. The documented distinction is that the C-More’s client drivers use PCCC or symbolic messaging over CIP, while I/O messaging is available through the Generic I/O Server role. If the control design specifically requires cyclic mapped I/O rather than client data access, return to the server decision instead of forcing a client driver.
Configure Generic I/O only for the C-More server role
Select “Allen-Bradley EtherNet/IP Server (Generic IO Messaging) (Control/CompactLogix)” when the C-More must be a slave/server node and the intended exchange is I/O mapping. This is the path associated with a starting address in the setup question.
- Confirm the PLC-side design expects the C-More to act as the server/slave node. If the intended relationship is panel-to-PLC HMI access, stop and use a client driver instead.
- Use the project’s I/O map and the installed C-More documentation to determine the start address and any related mapping values. The correct values depend on the specific configuration; do not copy a guessed offset.
- Configure the corresponding PLC-side connection and data layout to match the C-More server configuration. Check the device manuals and project configuration for the required connection details rather than assuming the client-driver IP entry applies.
- Validate the mapped data in both configurations before enabling control writes. Confirm that each field maps to the intended PLC data and direction.
The server-driver selection is not a workaround for an unsupported client target. It changes the communication role and data-exchange method, so use it only when the PLC and HMI configuration are designed for generic I/O mapping.
Verify the selected role before returning the panel to service
- Review the configured driver name and compare it with the intended role: a client driver for C-More-initiated PLC access, or Generic I/O Server for C-More server/slave I/O mapping.
- For a client connection, verify the target PLC/device IP address and check that the selected driver matches the actual AB device. For the cited SLC 5/05 case, check the “SLC5/05/ENI Adapter” selection.
- For a server connection, compare the configured start address and mapped data against the PLC-side I/O configuration and the product documentation.
- Test a known read value, then a controlled write if the application permits it. Confirm the value changes at the intended PLC point and that unrelated mapped values remain unchanged.
- If communication still fails, separate driver selection from network and data-mapping faults: check IP reachability, the target device configuration, and the relevant HMI/PLC diagnostics before changing addresses.
A successful network connection is not enough to validate an I/O map. Verify the meaning, direction, and destination of actual data before relying on the panel for machine operation.
Frequently asked questions
Why does C-More ask for a starting address for EtherNet/IP?
You have selected the “Allen-Bradley EtherNet/IP Server (Generic IO Messaging) (Control/CompactLogix)” driver. That driver is for the C-More acting as a server/slave node with I/O mapping, not the ordinary client path to a PLC.
Why does my C-More need an EtherNet/IP Client driver?
Use a client driver when the C-More is the HMI communicating with an AB PLC. Select the client variant for the target device and enter that device’s IP address.
Which C-More driver should I use for an SLC 5/05?
The cited example uses “SLC5/05/ENI Adapter” under the Allen-Bradley EtherNet/IP Client choices. Verify that the target is an SLC 5/05 before selecting it.
Why does choosing the Client driver not give me I/O mapping?
The client drivers use PCCC or symbolic messaging over CIP; the Generic I/O Server driver is the documented C-More I/O messaging path. Choose based on the required communication role and data exchange, not on the protocol name alone.
Can the C-More act as a slave on an AB EtherNet/IP network?
The Generic I/O Server driver is the described option for making the C-More a slave/server node with mapped I/O. Stop if the required address or mapping is unclear, or if the PLC-side configuration cannot be matched; contact AutomationDirect support through its official support channel before commissioning the connection.