Cannot read register values using pymodbus

Question

When I tried the following code, I can connect to the smart meter, but I'm not able to read the register content.

import traceback
from pymodbus.client.sync import ModbusTcpClient
client = ModbusTcpClient('192.168.2.1', port=502)
client.connect()

try:
    res = client.read_holding_registers(0x0063, 1, unit=1)
    print(res.registers)

except:
    traceback.print_exc()
    
client.close()

The gives an exception

  Traceback <Most recent call last>
    File "m2.py", Line 8 ,in <module>
    print<res.registers>
AttributeErro: 'ModbusIOException' objecthas noattribute 'registers'

Please help me to fix this

More information would help. Is there an exception? What is it? How do you know that you're connecting successfully? — Caleb, Dec 17 '20 at 17:47

score 0 · Answer 1 · answered Dec 19 '20 at 05:19

0

You might be missing the client.connect here

from pymodbus.client.sync import ModbusTcpClient
client = ModbusTcpClient(host='192.168.2.1', port=502)
client.connect() ### Added here

try:
   result = client.read_holding_registers(0x0063,1, unit=1)
   print (result.registers)

except Exception as e:
   print (e)

client.close()

answered Dec 19 '20 at 05:19

Vaebhav

1,471
5
21

Thanks for the reply , But when I tried your solution it gives and error like ModusIoException ' Object has no attribute registers' It will be great if you suggest a solution – Viju Poonthottam Dec 28 '20 at 18:21
@VijuPoonthottam - Can you post the `StackTrace` and update the question – Vaebhav Dec 29 '20 at 03:28
@ Vaebhav Edited and Posted – Viju Poonthottam Jan 01 '21 at 17:27

Cannot read register values using pymodbus

1 Answers1