C.4.5 checking the data, C.4.5, Checking the data – Festo Контроллеры двигателя SFC-LAC User Manual

Page 377: C−51

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C. Object directory DS402 and CI

C−51

Festo GDCP−SFC−LACI−CO−EN en 0812NH

C.4.5

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 mes−
sage will not appear in the response; rather, the received
value will always be returned (Echo).

Recommendation:
Check that values have been written correctly by downloadĆ
ing 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 imperĆ

missible value will be limited to the nearest permitted
value.

Error messages

If there are errors in the commands (e.g. syntax errors, transĆ
mission errors), the value <0x00FF> will be transmitted
(object 2FF0h) instead of the usual reply. Possible causes:

ć

Incorrect initial character, separating character or empty
character

ć

Incorrect hex digit

ć

Incorrect value type

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