User Guide

Interface Startup Parameters
6
Parameter
Description
Point Loading
0x0040
Time Functions
0x0400
Digital State Caching
0x2000
/DisableCounters
Optional
Windows Performance counters are enabled by default.
Counters can be disabled by specifying
/disablecounters on the command-line.
/ec
or
/ec=#
Optional
The first instance of the /ec parameter on the command-line
is used to specify a counter number, #, for an I/O Rate point.
If # is not specified, then the default event counter is 1. Also, if
the /ec parameter is not specified at all, there is still a default
event counter of 1 associated with the interface. If there is an
I/O Rate point that is associated with an event counter of 1,
each copy of the interface that is running without /ec=#
explicitly defined will write to the same I/O Rate point. This
means that one should either explicitly define an event
counter other than 1 for each copy of the interface or one
should not associate any I/O Rate points with event counter 1.
Configuration of I/O Rate points is discussed in the section I/O
Rate Points (page 25)
For interfaces that run on Windows nodes, subsequent
instances of the /ec parameter may be used by specific
interfaces to keep track of various input or output operations.
One must consult the interface-specific documentation to see
whether subsequent instances of the /ec parameter have
any effect. Subsequent instances of the /ec parameter can
be of the form /ec*, where * is any ASCII character
sequence. For example, /ecinput=10, /ecoutput=11,
and /ec=12 are legitimate choices for the second, third, and
fourth event counter strings.
/f=SS
or
/f=SS,SS
or
/f=HH:MM:SS
or
/f=HH:MM:SS,hh:mm:ss
Required for reading scan-
based inputs
The /f parameter defines the time period between scans in
terms of hours (HH), minutes (MM), and seconds (SS). The
scans can be scheduled to occur at discrete moments in time
with an optional time offset specified in terms of hours (hh),
minutes (mm), and seconds (ss). If HH and MM are omitted,
then the time period that is specified is assumed to be in
seconds.
Each instance of the /f parameter on the command-line
defines a scan class for the interface. There is no limit to the
number of scan classes that can be defined. The first
occurrence of the /f parameter on the command-line defines
the first scan class of the interface; the second occurrence
defines the second scan class, and so on. Historian Points are
associated with a particular scan class via the Location4
Historian Point attribute. For example, all Historian Points that
have Location4 set to 1 will receive input values at the
frequency defined by the first scan class. Similarly, all points
that have Location4 set to 2 will receive input values at the
frequency specified by the second scan class, and so on.
Two scan classes are defined in the following example:
/f=00:01:00,00:00:05 /f=00:00:07
or, equivalently:
/f=60,5 /f=7
The first scan class has a scanning frequency of 1 minute with