Hello to everyone. Nice to meet you all. I am programming a KINCO PLC model HP043-20DT using ladder on KINCO BUILDER. I need to establish a serial communication with my PC. The PLC has a RS485 port which I adapted it to USB to connect with my PC. The PLC allows, at least, two ways to establish serial communication: MODBUS or free-protocol. I've read the software manual and tried to reproduce the examples it provides using the instruction blocks for MODBUS (MBUSR and MBUSW) and free-protocol (XMT and RCV) communications. However, I could not receive the data on the PLC. I could effectively transmit data with XMT from the PLC to the PC and I could verify through a tool called Access Port. In relation to MODBUS, I am using a simulation tool called Multiway from OMRON, however, I get no response from the PLC. If any of you have some experience with this software or this device, I would like to ask you how could I solve the problem. Thank you for your attention. Kind regards.