Here's what SCADALynx can and can't do with Allen Bradley PLCs, specifically in relation to communication:
We can talk the native protocol (EtherNet/IP) on the Ethernet port. These also have a serial port in which we can talk DF1 or Modbus RTU but both have to be configured in the PLC (Modbus has to be configured in Ladder Logix so much more difficult). For these we’d much rather talk the native protocol on the Ethernet port.
Unfortunately, at this time we do not support the MicroLogix EtherNet/IP protocol.
The MicroLogix 1400 can be setup to respond to Modbus/TCP requests on the Ethernet port so that's an option.
We can only talk to a Micrologix 1000/1100/1200/1500 on the serial port (DF1 or Modbus RTU except for the 1000 which is DF1 only). Typically our preference would be DF1 via the serial port but if going through Ethernet is desire then the PLC must be set up for Modbus/TCP.
SLC 5-03/04/05 PLCs
All three support DF1 via serial port. There are some Ethernet add on cards for the 03/04 and the 05 has it built in, but we can’t communicate with these PLCs over those connections, so we use DF1 via serial to communicate to these PLCs.