Hi Nishant,
Do you not have any reactor at all?
You should be able to load the software without having a reactor involved if you disable all the “Initialise” functions in the software – these are responsible for checking reactors are there and setting default values for all the hardware.
If you do have a reactor, but it isn’t connecting properly and blaming the Multiplexer, there may be a fault with the PCB attached to the Beaglebone Black. This is a hardware issue with some boards – Labmaker should be able to fix it for you.
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