使用pymodbus进行modbus-TCP通信

模拟modbus-slave

创建slave

设置

完成

安装pymodbus

pip3 install pymodbus==2.5.3

代码

from pymodbus.client.sync import ModbusTcpClient
from pymodbus.bit_read_message import ReadCoilsResponse
from pymodbus.register_read_message import ReadInputRegistersResponse
from pymodbus.exceptions import ConnectionException      # 连接失败，用于异常处理
import time

host = '127.0.0.1'
port = 502
client = ModbusTcpClient(host,port)
print(client.connect())

while client.connect():
    print("connected")
    # 读取寄存器数据，不能超位读取
    result = client.read_holding_registers(0, 10, unit=1)
    print(result.registers)
    # 修改端口数据
    result = client.write_registers(0, [666, 888], unit=1)
    print(result)
    time.sleep(1)