C.1.5 checking the data, C.1.5, Checking the data – Festo Контроллеры двигателя SFC-LAC User Manual

Page 345

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C. CI interface

C−9

Festo GDCP−SFC−LACI−DN−EN en 0812NH

Note
All length specifications (also velocities and similar) are
saved in millimetres in the controller and are not converted
into the relevant unit of measurement system until they
are written or read.

Values must be converted to

increments before being

transmitted over the CI interface; see section A.3.

C.1.5

Checking the data

Permitted value ranges

Transferred parameters and values are checked by the SFC−
LACI before being accepted.

Note
In the case of invalid parameters or values, an error
message will not appear in the response; rather, the reĆ
ceived value will always be returned (Echo).

Recommendation
Check that values have been written correctly by
downloading the current contents of the object with a
subsequent Read command. The higher level controller must
compare the sent command with the Echo" from the
SFC−LACI and check the checksum.

Note
The following applies when writing the objects:

Ĉ Discrete values (values from a value list):

an invalid value will not be accepted; the previously
valid value will be retained.

Ĉ Continuous values (e.g. lengths, speeds, etc.):

an impermissible value will be limited to the nearest
permitted value.

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