Fl.net Module Communication Performance - Hitachi FL.NET User Manual

The contents of the above window are explained below:
On-screen item
Token maintenance node number
Minimum frame interval
Refresh cycle time
Refresh cycle measurement time (current)
Refresh cycle measurement time (maximum)
Refresh cycle measurement time (minimum)

5.3.7 FL.NET module communication performance

The method of calculating the communication performance of the FL-NET module is shown
below. However, the method varies depending on the destination of the connection and number
of words. Accordingly, the worst case scenario is shown below on the supposition of
communication performance between FL-NET modules.
The meanings of symbols used in the expression are shown below.
S: Number of transmitted words of the self-node (words)
R: Number of received words sent from the previous node to the self-node (words)
F: Quotient resulting from dividing (S - 1) by 512
(Example: F = 0 when S = 512, F = 1 when S = 513)
Fn: F of each node. n is the node number.
RCT: Refresh cycle time (ms)
SCT: Sequence cycle time (ms)
MS: Transmitted message word count (bytes)
MR: Received message word count (bytes)
MFT: Minimum frame interval (ms)
W: Total number of transmitted words of all nodes (words)
n: Number of connected nodes
Description
This is the node number of the node that currently
holds the token.
This value denotes the minimum frame interval that
is allowed on the network.
It represents the maximum value of the nodes that
compose the network.
This value is 1.2 times the time required for a token
circulation through the network.
These values are the current value, maximum value,
or minimum value of the measured time required for
a token circulation through the network.
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5 USER GUIDE