Union Switch & Signal GENISYS II, Hardware Installation

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GENISYS II System Hardware Installation UNION SWITCH & SIGNAL
SM-6900B Rev. 0.0 August 1999 3-11
transmitting the first byte of the response). The worst case delays for the communication channel
may be determined by referring to application information for the communication equipment
being used. The worst case turnaround delay for a GENISYS II slave port is typically less than 50
milliseconds. The average turnaround delay is less than 20 milliseconds.
The master port polling interval parameter (POLLING.INTERVAL) is provided to adjust
communication loading on a GENISYS II unit that is heavily loaded (many complex logic
equations in the application program that execute very frequently). The polling interval is the
time inserted between the completion of one message exchange initiated by the master port and
the start of the next. Typically, the default value for this parameter should be used. Increasing the
value of this parameter decreases the load on the GENISYS II processor due to communications
and increases communication delays because additional time is inserted between messages
transmitted by the master. Decreasing the value of this parameter increases the load on the
GENISYS II processor due to communications and decreases communication delays. This
parameter should be adjusted only if processor loading problems have been confirmed.