使用ModbusTcpClient库在Mitsubishi PLC上进行Python modbus通信读取字

时间:2017-04-11 11:44:16

标签: python plc modbus-tcp

我正在尝试使用以下代码与Mitsubishi PLC(Q06udeh)上的文字进行沟通和阅读:

from pymodbus.client.sync import ModbusTcpClient

client = ModbusTcpClient('10.1.1.4',port=5007)
client.connect()

result = client.read_holding_registers(1,1)
print result
t = result.registers[0]
print t

我得到以下输出:

None

Traceback (most recent call last):
  File "C:\Users\serkan\Desktop\sasda.py", line 8, in <module>
    t = result.registers[0]
 AttributeError: 'NoneType' object has no attribute 'registers'

无论我如何改变不同参数的访问单词都没有希望,我仍然没有成功。

请帮忙。

1 个答案:

答案 0 :(得分:1)

使用modbus_tk

首先,您需要安装modbus_tk包:

pip install modbus_tk

然后,尝试运行此示例代码:

#  General MODBUS includes
import modbus_tk
import modbus_tk.defines as cst
# TCP MODBUS includes
from modbus_tk import modbus_tcp

def main():
    device_id = 1
    master = modbus_tcp.TcpMaster("10.1.1.4")
    master.set_timeout(3)     #it's really optional
    master.set_verbose(True)  # this is optional too
    data = master.execute(device_id, cst.READ_HOLDING_REGISTERS, 100, 1) #Usage: 100 is registry number and 1 means that size of data is 16bit (modbus protocol specification)
    print "data    ", data
    print "data[0] ", data[0]

if __name__ == "__main__":
    main()

您可以在此处找到更多示例: https://github.com/ljean/modbus-tk/tree/master/examples