The C-more Ethernet driver described for this pairing uses I/O-type CIP Ethernet/IP, which the MicroLogix 1100 Ethernet interface does not support; an Ethernet cable and valid IP settings do not resolve that protocol mismatch.
Compatibility decision for the MicroLogix 1100
Before wiring the HMI or changing PLC communications, confirm the exact C-more model, programming-software version, and available MicroLogix driver. The compatibility statement for this pairing is specific to the C-more Ethernet communication method described: it does not establish whether a later HMI model or driver adds a different supported method.
- Open the device or PLC driver selection in the C-more project software.
- Look for a driver explicitly intended for the MicroLogix 1100 over Ethernet. Confirm that its documented protocol matches the PLC interface; a generic Ethernet/IP or I/O-type driver is not a substitute.
- If no matching supported driver is listed, choose a supported serial method or a different HMI/interface. Do not proceed on the assumption that matching IP subnets make the devices protocol-compatible.
Use the current C-more and PLC documentation for the exact supported driver names, firmware constraints, and wiring details. The 2006 compatibility answer identifies DF1 or DH485 as possible alternatives, but does not give model-specific settings.
Why Ethernet connectivity does not establish compatibility
Ethernet defines the physical and network transport path; the endpoints still need a compatible application protocol and data model. An HMI can have link, obtain or use a valid IP address, and reach a PLC at the network layer while still being unable to read or write PLC data.
In this case, the reported C-more Ethernet method uses I/O-type CIP Ethernet/IP. The reported MicroLogix 1100 Ethernet port does not support that method. Consequently, successful ping or link indications would confirm only network reachability, not that the HMI driver can exchange tags or data-table values with the controller.
Communication approaches and selection criteria
| Approach | What must match | Selection guidance |
|---|---|---|
| C-more Ethernet driver | A C-more driver specifically supporting the MicroLogix 1100 and the PLC's Ethernet protocol | Use only when the installed software's driver documentation explicitly lists the PLC and connection method. |
| DF1 serial | Supported C-more and PLC drivers, compatible serial interfaces, cable pinout, and matching communication settings | A stated alternative for this pairing; confirm the applicable manuals before wiring or configuring. |
| DH485 serial | Supported drivers and interfaces, network or point-to-point arrangement, and matching settings | Also identified as a possible alternative; verify the exact hardware and topology requirements first. |
Prefer the Ethernet path only if the exact installed C-more driver explicitly supports this PLC over its Ethernet interface. Otherwise, select DF1 or DH485 only after confirming both endpoints support the selected protocol and the required physical interface. Do not treat DF1 and DH485 as interchangeable settings.
Prerequisites before configuring a serial alternative
Collect the exact C-more model and software version, MicroLogix 1100 catalog information, PLC firmware, and manuals for both communication interfaces. Identify the intended protocol and port on each device. Read the documented cable type and pinout, electrical interface, and serial parameters; do not guess baud rate, parity, station address, or cable wiring.
Confirm that the HMI driver supports the PLC model and the chosen protocol before building screens. A driver that supports a related controller or a protocol over a different interface is not sufficient. Record the PLC data addresses and data types required by the HMI, then map them using the driver's documented address syntax.
Configure and verify the selected connection
- Confirm the driver. Select the documented MicroLogix-compatible driver for the chosen protocol. Verify that the driver description identifies the intended physical interface and controller family.
- Set both endpoints. Configure matching serial communication parameters and the documented station or node settings. Confirm the selected PLC port and HMI interface support the same electrical connection before connecting the cable.
- Check the wiring. Compare the cable pinout against both device manuals, including transmit/receive and signal reference requirements. Confirm the PLC is powered and the selected port is enabled for the chosen protocol.
- Map one test value. Use a known PLC data address and compatible data type. Start with a read-only display where possible; verify the PLC value in its programming software while comparing the HMI display.
- Test writes only after reads succeed. Use a controlled, nonhazardous test value and confirm the change at the PLC. Then restore the intended application value and validate each required address and data type.
If a serial test fails, inspect the HMI communication status, PLC port configuration, cable pinout, protocol selection, and matching serial settings in that order. If Ethernet link or ping succeeds but PLC data remains unavailable, return to driver/protocol compatibility rather than repeatedly changing IP settings.
Frequently asked questions
Can I connect a C-more to a MicroLogix 1100 over Ethernet?
Only if the exact C-more driver supports the MicroLogix 1100's Ethernet communication method. The Ethernet method described for this pairing uses I/O-type CIP Ethernet/IP, which the PLC interface does not support.
Does a successful ping prove the HMI can read the PLC?
No. Ping confirms network-layer reachability, not application-protocol or driver compatibility. Verify that the C-more driver explicitly supports the PLC over Ethernet.
Can I use DF1 or DH485 instead?
Both were identified as possible alternatives for this pairing. Confirm support in the current C-more and PLC documentation, then match the driver, interface, cable, and communication settings.
How do I verify a serial C-more connection?
Read a known PLC value and compare it with the value shown in the PLC programming software. After reads succeed, test a controlled write and confirm the resulting PLC value.