Yaskawa Remote I/O Controller LAN Node PCB for use with Microtrac DSD LAN - Manual (Page 5)

update LAN message is sent to each of the
drives that had previously asked to be
updated. The drives that had previously
asked to be updated will also be updated at
4 second intervals, for redundancy in case
of a previous communication failure.
When specifying a Numeric input, a
decimal point location value must be
defined. This value is used to determine
where the decimal point is in order to scale
the value read from the Thumbwheel Switch
Bank (since there is no way to read the
decimal point location). The value read
from the Thumbwheel Switch Bank sent to
the drive will be in a floating point format.
The decimal point location value is the
number of digits to the right of the decimal
point. The acceptable decimal point values
are in the range of 0 through 6. Decimal
point values received higher than 6 will be
set internally to 6.
Numeric Inputs From D/A Output Sources
A drive may request Numeric input
updates from D/A output sources. This
means that a drive can place the burden of
keeping it updated (with the value of a
numeric output) onto the RIO, and not put
the burden on another drive. Numeric
update messages are sent to all concerned
drives at regular intervals (approximately
140 ms per interval). The value sent is in a
floating point format and will range from -1
to +1, corresponding to -maximum analog
input value to +maximum analog input
value, respectively.
When specifying a Numeric input, a
decimal point location value must be
defined. This value is ignored when the
Numeric input is from a D/A source.
NUMERIC OUTPUTS
Numeric outputs are any numeric
type outputs, such as an analog output.
Numeric update messages are expected by
the RIO from the drives. The value received
is expected to be in a floating point format
in the range from -1 to +1, corresponding to
-maximum analog output value to
+maximum analog output value,
respectively.
When first powered up, the RIO will
drive all of the outputs to 0. The RIO will
also announce its power up state onto the
LAN so that any concerned drives may
allocate outputs and request inputs. Drives
will also allocate outputs and request
inputs when they are first powered up in
case they are powered up after the RIO is
powered up (thus not seeing the RIO power-
up announcement on the LAN). The first
drive to allocate an output will have
exclusive rights of controlling the output.
Any drives trying to allocate an already
allocated output will receive an error
message and not be allowed to control the
output.
When specifying an analog output,
an output time needs to be defined. The
output time is entered in number of whole
seconds, not to exceed 36. An entered time
of 0 means to never time out. This output
time is used by the RIO to determine if the
drive is communicating with the RIO. Each
drive that has allocated an output has an
output timer in the RIO. A drive’s output
timer is reset to the original output time
each time that an output update message is
received by the RIO from the drive through
the LAN. When a drive’s output timer times
out, the RIO assumes that communication
with the drive is no longer occuring; thus all
of the outputs that the drive has allocated
will be driven to 0.
Furthermore, when specifying an
output, a fault reaction must be defined. A
fault reaction may be defined as either
Allocate or Deallocate. If a drive’s output
timer times out, the fault reaction
determines what the RIO should do. If
defined as Allocate, then the output will
remain allocated to the drive. If defined as
Deallocate, then the output will no longer be
allocated to the drive. Consider the
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