- 功能码列表:
0x01 读线圈状态(Read Coils)
0x02 读离散输入状态(Read Discrete Inputs )
0x03 读保持寄存器(Read Holding Registers )
0x04 读输入寄存器(Read Input Registers)
0x05 写单线圈(Write Single Coil )
0x06 写单寄存器(Write Single Register)
0x07 读取异常状态(限串行线)(Read Exception Status (Serial Line only) )
0x08 通信系统诊断(限串行线)(Diagnostics (Serial Line only) )
0x09-0x0A无
0x0B 获取串行通信事件计数器(Get Comm Event Counter (Serial Line only) )
0x0C 获取串行通信事件日志 ( Get Comm Event Log (Serial Line only) )
0x0D-0x0E无
0x0F 写多个线圈(Write Multiple Coils)
0x10 写多个寄存器(Write Multiple registers)
0x11 报告服务器ID(仅串行线)(Report Server ID (Serial Line only) )
0x12-0x13无
0x14 读文件记录(Read File Record )
0x15 写文件记录(Write File Record)
0x16 带屏蔽字写入寄存器(Mask Write Register )
0x17 读/写多个寄存器(Read/Write Multiple registers)
0x18 读取先进先出(FIFO)队列(Read FIFO Queue)
0x19-0x2A无
0x2B 封装接口传输(Encapsulated Interface Transport .)
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分主站,从站,主站是客户端,从站是服务端。启动时先启动从站(服务端),然后主站再连上从站,获取信息。
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Device and Modbus 地址表(最大地址看设备)
|----------------|----------------|-------------------|----------|------------|-----------------|
| Device address | Modbus address | Description | Function | R/W | Comments |
| 1...10000 | address-1 | Coils(outputs) | 01 | Read/Write | 05 and 15 |
| 10001...20000 | address-10001 | Discrete Inputs | 02 | Read | |
| 40001...50000 | address-40001 | Holding Registers | 03 | Read/Write | 06,16,22 and 23 |
| 30001...40000 | address-30001 | Input Registers | 04 | Read |