Technical Manual PD4-E-M (EtherCAT)
10 Description of the object dictionary
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VISIBLE_STRING: The object describes a character string coded in ASCII. The length of the
string is specified in subindex 0; the individual characters are stored beginning in subindex 1.
These character strings are not terminated by a null character.
Data type
The size and interpretation of the object is specified here. The following notation is used for the
"VARIABLE" object code:
•
A distinction is made between entries that are signed; these are designated with the prefix
"SIGNED". For entries that are unsigned, the prefix "UNSIGNED" is used.
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The size of the variable in bits is placed before the prefix and can be 8, 16 or 32.
Savable
Described here is whether this object is savable and, if so, in which category.
Firmware version
The firmware version beginning with which the object is available is entered here.
Change history (ChangeLog)
Any changes to the object are noted here.
There are also the following table entries for the "VARIABLE" data type:
Access
The access restriction is entered here. The following restrictions are available:
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"read/write": The object can both be read as well as written
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"read only": The object can only be read from the object dictionary. It is not possible to set a
value.
PDO mapping
Some bus systems, such as CANopen or EtherCAT, support PDO mapping. Described in this
table entry is whether the object can be inserted into a mapping and, if so, into which. The
following designations are available here:
•
"no": The object may not be entered in a mapping.
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"TX-PDO": The object may be entered in an RX mapping.
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"RX-PDO": The object may be entered in a TX mapping.
Allowed values
In some cases, only certain values may be written in the object. If this is the case, these values
are listed here. If there are no restrictions, the field is empty.
Preset value
To bring the controller to a secured state when switching on, it is necessary to preset a number
of objects with values. The value that is written in the object when the controller is started is
noted in this table entry.
10.4 Value description
Note
For the sake of clarity, a number of subindices are grouped together if the entries all have the same
name.
Version: 1.0.1 / FIR-v1748
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