Technical Manual N5 (CANopen)
10 Description of the object dictionary
Listed in the table with the "Value description" heading are all data for sub-entries with subindex 1 or
higher. The table contains the following entries:
Subindex
Number of the currently written sub-entry.
Name
Name of the sub-entry.
Data type
The size and interpretation of the sub-entry is specified here. The following notation always
applies here:
•
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.
•
The size of the variable in bits is placed before the prefix and can be 8, 16 or 32.
Access
The access restriction for the sub-entry is entered here. The following restrictions are available:
•
"read/write": The object can both be read as well as written
•
"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 sub-entry 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.
•
"TX-PDO": The object may be entered in an RX mapping.
•
"RX-PDO": The object may be entered in a TX mapping.
Allowed values
In some cases, only certain values may be written in the sub-entry. 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 sub-entries with values. The value that is written in the sub-entry when the controller is
started is noted in this table entry.
10.5 Description
This section may be present if use requires additional information. If individual bits of an object or sub-
entry have different meaning, diagrams as shown in the following example are used.
Example: The object is 8 bits in size; bit 0 and bit 1 have different functions. Bits 2 and 3 are grouped
into one function; the same applies for bits 4 to 7.
Example [4]
7
6
5
4
3
2
1
0
Example [2]
B
A
Example [4]
Description of bit 4 up to and including bit 7; these bits are logically related. The 4 in square
brackets specifies the number of related bits. A list with possible values and their description is
often attached at this point.
Version: 2.0.1 / FIR-v1650
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