I integrate the Power Boost EM112 from Carlo Gavazzi into Home Assistant via RS485 (Modbus)

Important information

Note that the integration described below can only work if the USB/RS485 stick is the only equipment on the RS485 bus connected to the EM112. Indeed (and with the help of Eric G.) I understood that there could only bea single master equipment on the bus. The master is the one who questions and the slave the one who answers. EM112 is therefore a slave.

My first idea was to sniff out the lines of dialogue between EM112 and my Wallbox, the Wallbox being the master, I cannot do that. For the beauty of the exercise, I tested with two masters, it works we find values but from time to time, when the two masters ask a question together, we find ourselves with an error.

If someone can point me towards a way of ‘snipping’ bus 485 to intercept the information that the EM112 sends to a Wallbox, for example, I am a taker because at this stage I cannot have a Wallbox and a RS485/USB Key in parallel (two masters).

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