Devices, Systems, and Methods Regarding Programmable Logic Controller Communications

A method comprising:

• causing a signal to be transmitted between a programmable logic controller and an Input/Output (I/O) module via a signal interface, said programmable logic controller adapted to use said signal to control a process, said programmable logic controller communicatively coupled to said I/O module via an opto-coupler, said signal comprising a clock sub-signal and an integrated control sub-signal, said clock sub-signal adapted to provide temporal information regarding said signal, said control sub-signal a framing signal indicative of a completion of a register transfer, a circuit receiving said signal adapted to recover said clock sub-signal and said control sub-signal from said signal, said circuit adapted to detect said control sub-signal via differentiation of short length pulses from pulses that have a longer length.

A machine-readable medium comprising machine-implementable instructions for activities comprising:

• transmitting a signal between a programmable logic controller and an Input/Output (I/O) module via a signal interface, said programmable logic controller adapted to use said signal to control a process, said programmable logic controller communicatively coupled to said I/O module via an opto-coupler, said signal comprising a clock sub-signal and an integrated control sub-signal, said clock sub-signal adapted to provide temporal information regarding said signal, said control sub-signal a framing signal indicative of a completion of a register transfer, a circuit receiving said signal adapted to recover said clock sub-signal and said control sub-signal from said signal, said circuit adapted to detect said control sub-signal via differentiation of short length pulses from pulses that have a longer length.