6100 MPS-B Programming Manual

WRITING APPLICATIONS THAT USE 6100 MPS-B

Define Slow Poll List

This form of the request is used to define a list of slow poll

time intervals station by station. The slow poll time interval

determines when a station will be removed from the nonresponding

station list.

Initially, when you define (or redefine) the poll/select list, a

slow poll list is created, having a slow poll time interval of

zero. This zero value indicates that the station associated with

this entry can be removed from the nonresponding station list

only upon a specific application process request--that is, a

specific request to remove all stations from the nonresponding

list.

The Define Slow Poll List request permits you to define a slow

poll time interval, in .01 second increments, that dictates when

a station previously placed in the nonresponding station list

will be removed from that list. That is, if you specify a slow

poll time interval of one second for station 3, and station 3

becomes added to the nonresponding station list, it will be

removed automatically from the nonresponding station list one

second later.

Notice that a slow poll list entry of zero indicates that a

station remains in the nonresponding station list indefinitely

(until explicitly removed from the list through a Remove Stations

From Nonresponding List request).

The first time a station is placed in the nonresponding station

list, the READ request response buffer contains a status code 162

(request timed out on select). If the station is removed from

the nonresponding station list through the slow poll mechanism

and the response from the station is EOT, then the READ request

response buffer contains a status code 163 (EOT received).

Conversely, if the station fails to respond, it is immediately

placed back in the nonresponding station list, its slow poll

time interval is re-established, and it will be removed from the

nonresponding station list upon expiration of the slow poll time

interval.

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