这是用Delphi+spcomm开发的基于MODBUS协议的RTU程序，有需要的可以自由下载-This is used Delphi+ Spcomm development of RTU based on MODBUS protocol procedures, are in need can freely download

Delphi的ModbusTcp开发控件，需要Indy支持，包括主站和从站的控件-he Delphi Modbus library is a Modbus Class I Delphi implementation of a Modbus master and slave over TCP/IP (ModbusTCP). Serial I/O (RTU or ASCII) is not supported.