You can download the software kit here for the HMI to find out how easy it's to build your own interfaces. There are lots of sample codes and projects for you to start with here. Try to create a new project, you can see if your PLC's communication protocol is supported. Although we are happy to customize a protocol support with a extra fee, MODBUS (RTU over RS485/RS422 or TCP over Ethernet) is the universal protocol for PLC and HMI communication and should be your go-to option if your protocol happens to be not on our long list of supported protocols.