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Host Link Status
This Bool variable will indicate any failure on the host communications link. If
this variable is True, it indicates normal communications to on the host link. If
variable value is equal to False, it indicates an interruption in communications
on the host link. Connectors J1 and J2 (3000S only) on the front of a 3000
node processor function as the Host Ethernet Link
Interlink Link Status
This Bool variable will indicate any failure on the communications link between
the Node Processors. If this variable is True, it indicates normal
communications on the interlink. If the variable value is equal to False, it
indicates an interruption in communications on the link. Connector J2 on the
front of a redundant 3000 node processor functions as the Interlink Port to
other redundant node processors. This variable should be monitored only in
3000D, 3000T and 3000Q SIS!
I/O Path A Link Status
This Bool variable will indicate any failure on the communications link between
the selected Node Processor and Chassis Processors on Port A. If this
variable is True, it indicates normal communications on Port A of the I/O
communications link. Connector J3 on the front of a redundant 3000-node
processor functions as the A I/O Port to the chassis processors.
I/O Path B Link Status
This Bool variable will indicate any failure on the communications link between
the selected Node Processor and Chassis Processors on Port B. If this
variable is True, it indicates normal communications on Port B of the I/O
communications link. Connector J4 on the front of a 3000 Node Processor
functions as the B I/O Port to the chassis processors.
Scan Cycle
This integer variable indicates the time for one scan cycle in 100 microsecond
units. If the scan cycle is configured for 25 milliseconds, then the value of this
variable should indicate 250. The Node Processor includes a Windowed
Watchdog Timer (WWDT) with a minimum of 3 milliseconds and a maximum
of 80 milliseconds. If the node processor deviates from this window, a board
reset is asserted. The 3000 chassis processor has a fixed scan rate of 1
millisecond, and includes a Windowed Watchdog Timer (WWDT) with a
minimum of 0.5 milliseconds and a maximum of 12 milliseconds. If the
chassis processor deviates from this window, a board reset is asserted.
Scan Reserve
This integer variable indicates the idle time that the selected Node Processor
has on each scan cycle. For example if the Scan Cycle is 50 and the Scan
Reserve is 30 for Node Processor A, then we can assume the following: The
Node Processor A’s overall cycle time is 5 milliseconds, it completes all its
scan and communications functions within 2 milliseconds, and has 3
milliseconds in reserve delay time. If reserve cycle time is not enough, then
the scan cycle should be re-configured. Minimum 1 millisecond reserve time
is recommended.
I/O Comm. Error Count
This integer variable will count the number of invalid I/O communication
messages (detected by multiple CRC signatures on each message). If a
Node Processor does not receive a valid I/O communication message for
three consecutive scan cycles from any of the configured Chassis Processors
and its redundant processor(s) does, then the Node Processor will take itself
offline.
Peer Comm. Error Count
This integer variable will count the number of invalid peer-to-peer
communication messages (detected by multiple CRC signatures on each
message). If a Node Processor peer-to-peer message miss-compares for
three consecutive scan cycles then the Node Processor will take itself offline.
