In Fieldbus, Digital Control is Possible?

Can Switches Or On-off Valves Be Connected On The Same Bus As Continuous Measurement Or Control Devices? If This Is Possible, How Is The 0 And 1 Signal Encoded?

Yes, they can. In the IEC and FF protocols, discrete variables are encoded as 8-bit unsigned integers. I assume the value would be either 0 or 1. As for all measurements, an 8-bit status value is always sent with it.