COMMAND NAME:

        OPEN

ABBREVIATION:

        O

USAGE:
        Interactive dialogue:

        sim> OPEN
        signal name> {'signal-name' | pt | PRIMARY_IO}
              .
              .
              .
        signal name> ;

        or single entry:

        OPEN {'signal-name' | pt | PRIMARY_IO}

        The OPEN command causes the history of the opened signal(s)
        to be recorded in the binary activity file.  If the Display
        Analyzer is run concurrently with the simulator, the waveforms
        of the open signals are displayed in the Display Analyzer 
        window.  If you open a bus (multi-bit) signal, the value is
        displayed in the current radix.  (See RADIX command.)

        The keyword PRIMARY_IO, which may be abbreviated to PIO,
        indicates that all primary inputs, outputs and bidirectional
        signals should be opened.  Primary I/Os are indicated by FLAG
        bodies on the root drawing of a design.  

        The simulator remembers which signal was opened last.  This
        signal is referred to as the "currently open" signal.  You 
        can DEPOSIT values to the currently open signal without
        specifying the name in the DEPOSIT command.

        The OPEN command can also be entered in the Display Analyzer,
        except for the PRIMARY_IO option.  If you are running the
        simulator and the Display Analyzer concurrently, the effect of
        the command is identical regardless of which window it is
        entered in.

        The Display Analyzer may be used as a post-processor to view
        waveforms after you have exited from the simulator.  In this
        mode the OPEN command is only required if you recorded the
        signal histories using RECORD SIGNAL or RECORD ALL.

EXAMPLES:
        O PIO         
        /* opens all signals which have FLAG bodies on the root drawing */

        OPEN
        signal name> 'sesame'
        signal name> 'minded'
        signal name> 'season'
        signal name> ;
        /* Opens the signals sesame, minded and season.  The names can 
           be entered most easily by pucking in GED.  This example also
           illustrates what a multi-line comment looks like in SCL. */

        OPEN 'system'
        DEPOSIT,1
        /* opens the signal called "system" and deposits logic 1 into it */

