Processes are composed of sequential statements, but processes are themselves concurrent statements. (See the “Concurrent Statements” chapter.) All processes in a design execute concurrently. However, at any given time, only one sequential statement is interpreted within each process.
A process communicates with the rest of a design by reading or writing values to and from signals or ports declared outside the process.
Sequential algorithms can be expressed as subprograms and can be called sequentially (as described in this chapter) or concurrently (as described in the “Concurrent Statements” chapter).
The following are sequential statements.
