How to monitor modbus?

[baggins]

Hi,

I have two Daikin Altherma heat pumps that are connected to a Zennio KLIC-DA interface.
The KLIC-DA does what it has to do (I can read all values that I want) but I have discovered a bug when reading power consumption and production.

The problem is that the values for power are only read by the KLIC-DA after manually reading them on the control panel on the heatpump...
I contacted Zennio and they acknowledged the bug (they modified their KLIC-DA manual to that effect). I opened a ticket with Zennio to solve the problem but more than one year later, nothing has happened...

Obviously I don't want to go over to the heat pumps to read the values of power every hour or even every day. That is not really in the concept of the smart home...
Now I had the following idea:
Since Daikin uses modbus to communicate between the control panel and the heat pump (and the KLIC-DA interface also), I wonder if I could monitor the bus to find out what happens when the power values are read with the control panel.
With that information I could then use LM to perform the same operation and the KLIC-DA interface could then read the power data.

Does anyone have experience with monitoring  modbus?
Obviously I would need a USB to RS385 interface and some modbus monitoring software to run on a laptop.
I looked around for the USB interface but apparently not all of them are suitable for modbus.

So to start: any idea of a suitable adapter and of software (preferably free...)?

Thanks in advance.

[admin]

You can use any USB-RS485 converter, you just need to know the baudrate, stop bits and parity. For serial data monitoring you can use RealTerm https://sourceforge.net/projects/realterm/, it has an option to display binary data in HEX. Then you can use this online tool to parse ModBus request/response: http://modbus.rapidscada.net/

You can also connect RS485 to LM an write a simple script to log incoming data.

[baggins]

You can use any USB-RS485 converter, you just need to know the baudrate, stop bits and parity. For serial data monitoring you can use RealTerm https://sourceforge.net/projects/realterm/, it has an option to display binary data in HEX. Then you can use this online tool to parse ModBus request/response: http://modbus.rapidscada.net/

You can also connect RS485 to LM an write a simple script to log incoming data.

Thanks admin, all the best for 2019!