连接到PLC时，如何在Raspberry Pi 3上修复ipython ConnectionException：Modbus错误？

编程问答 2022-08-11

问题描述

我在网上阅读到Modbus异常问题相对容易解决，但是由于我的经验不足，很难解决。我有一个VersaMax Nano Controller IC200NDR010-FJ，我正在尝试通过串行通信与树莓派3进行通信。

我已通过sudo raspi-config

配置了串行通信

我正在使用ipython，希望可以指出正确的方向。

Python 2.7.16 (default,Apr  6 2019,01:42:57) 
Type "copyright","credits" or "license" for more information.

IPython 5.9.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object',use 'object??' for extra details.

In [1]: from pymodbus.client.sync import ModbusSerialClient

In [2]: VersaMax = ModbusSerialClient(method='rtu',port=' /dev/ttyS0',baudrate=9600,timeout=2000,parity='O')

In [3]: VersaMax.read_coils(2048,1,unit=1).bits
---------------------------------------------------------------------------
ConnectionException                       Traceback (most recent call last)
<ipython-input-3-1bbc9781f264> in <module>()
----> 1 VersaMax.read_coils(2048,unit=1).bits

/home/pi/.local/lib/python2.7/site-packages/pymodbus/client/common.pyc in read_coils(self,address,count,**kwargs)
     46         '''
     47         request = ReadCoilsRequest(address,**kwargs)
---> 48         return self.execute(request)
     49 
     50     def read_discrete_inputs(self,count=1,**kwargs):

/home/pi/.local/lib/python2.7/site-packages/pymodbus/client/sync.pyc in execute(self,request)
    105         """
    106         if not self.connect():
--> 107             raise ConnectionException("Failed to connect[%s]" % (self.__str__()))
    108         return self.transaction.execute(request)
    109 

ConnectionException: Modbus Error: [Connection] Failed to connect[ModbusSerialClient(rtu baud[9600])]

In [4]:

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。

小编邮箱:dio#foxmail.com (将#修改为@）

ipythonmodbusmodbus-tcpplcplcpymodbus