The protocol library stack designed and developed by GCT Lab for Renesas RA series MCUs supports Modbus, IEC 60870-5-101 and IEC 60870-5-104 communication standards. The optimized embedded Modbus TCP/IP and RTU stack enables communication with multiple clients and servers using ProtoKit application software developed and ported onto Renesas RA6M3 MCU by GCT Labs. It is easily ported to other RA microcontrollers with Ethernet functionality.