From the looks of it, a IND.I/O base board only needs power and I2C signals (forget about the RS485). Are any other control signals needed for using it stand-alone?
BTW I am thinking of using industruino proto with an I2C multiplexer with multiple IND.I/O base boards to expand the number of I/O channels, without resorting to modbus etc.
Edit: related to this, I noticed the I/O base board cannot be bought separately?
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