This port is a connection point for a control link.
An output control port is ordinarily quiescent. When “poked” by a box it is on, however, it emits an infinitesimally short control “pulse” that can be transmitted instantaneously to other (input) control ports via a control link.
An input control port “listens” for control pulses and notifies the box it is on that such a pulse has been received. It acts exactly like a flip-flop whose value is set to “one” by a received control pulse, and whose value is reset to “zero” by the box it is on. The action of the box in response to a pulse on a particular input control port depends on its function, of course.
61
This is a primitive part in the “Concurrent” interpretation.
633
This port is a connection point for a data link.
An output data port is ordinarily quiescent. When “written to” by a box it is on, however, it emits for an infinitesimally short time a data value that can be transmitted instantaneously to other (input) data ports via a data link.
An input data port “listens” for data values and remembers the data value when it receives one. It acts exactly like a register whose value is set whenever a data value is received. (The new value overwrites any previous value that may have been in this register.) The box it is on may “read” the data value from any input data port at any time.
61
This is a primitive part in the “Concurrent” interpretation.
166
This link transmits a control “pulse” instantaneously from any output control port connected to its left end, to every input control port connected to its right end.
61
This is a primitive part in the “Concurrent” interpretation.
155
This link transmits a data value instantaneously from any output data port connected to its left end, to every input data port connected to its right end.
61
This is a primitive part in the “Concurrent” interpretation.
