6100 MPS-B Programming Manual

WRITING APPLICATIONS THAT USE 6100 MPS-B
Defining and Controlling the Poll/Select List
A configuration change immediately influences action on the line.
If multiple applications use the line, be careful about any
changes you make, and when you make them. To avoid problems,
consider the following strategies:
• If applications use different values of line configuration
parameters, try to use different lines for the stations they
address.
• Allow only the first opener to set or change the
configuration, and issue the SET CONFIGURATION request
immediately after the call to OPEN. Then you can be sure not
to change parameters while any application has a session in
progress.
The SET CONFIGURATION request is described later in this section.
DEFINING AND CONTROLLING THE POLL/SELECT LIST
The application must define the station poll/select list and can
maintain control over the stations on the list. The list is
defined by a call to WRITEREAD containing a POLL/SELECT LIST
CONTROL request with the Define Poll/Select List modifier. This
same request (with other modifiers) can be used to enable either
continuous or noncontinuous polling, halt polling, remove all
stations from the nonresponding list, or define a slow poll
list.
Stations to be polled or selected by 6100 MPS-B need to be
defined in a poll/select list. Your application process is
responsible for defining this list by issuing a specific Define
Poll/Select List request to 6100 MPS-B.
You may define a station in any of the formats recognized by 6100
MPS-B. That is, any station on the poll/select list can be
defined for the Fast Select sequence as well as the normal select
sequence.
Except for a Specific Poll of a station, 6100 MPS-B maintains the
poll/select list in round-robin fashion--traversing through the
list, station by station, as if there were no beginning or end.
The application maintains control over the stations on the
poll/select list by making a WRITEREAD call containing a STATION
CONTROL request with modifiers that enable or disable a station,
or alter a limited set of line configuration parameters
(specifically, the Connect Timeout, Timeout, Poll Interval,
Retries, and Pace parameters).
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