i have a heat recovery ventillation system controlled with an HMI,it has 2 motors, one for air ventillation and one for air extraction,with the possibility of controlling the speed of the ventillation (speed of the motors)
i want to control the heat recovery system by changing the speed of both motors with a smartphone, via an arduino
the HMI is connected to the main board of the system through an RS 485 communication standard(as written in the manual) 4 wires: (2 wires for power:0V and 12V, and 2 wires A and B for data)
i am new in this field and i had the idea of somehow getting the data signals for each function of the controller and then recreating those signals with the arduino
what to do ?!