Moog ACV with CANopen bus interface
2 Access over CANopen
CANopen object dictionary (OD)
B99224-DV018-D-211, Rev. A, October 2018
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2.4.3 Units and prefix parameter
This chapter describes the coding of units and prefix parameters according to CiA 303-2. Some objects pro-
vide unit and prefix in the sub-indices 2 and 3 to allow the master controller the correct visualization.
2.5 CANopen object dictionary (OD)
CANopen devices have an object dictionary, which is used for configuration and non-realtime communication
with the device. It is essentially a grouping of objects accessible via the network. Each object within the object
dictionary is addressed using a 16 bit index and an 8 bit sub-index. So an object can contain 256 parameters
which are addressed by the sub-index. The object dictionary is structured in several index ranges. The classi-
fication of the object dictionary is defined in the CiA 301.
Name of unit
International symbol
Notation index (hex)
none
dimensionless or iR
0x00
meter
m
0x01
second
s
0x03
hertz
Hz
0x20
liter
l or L
0x44
minute (time)
min
0x47
hour
h
0x48
day
d
0x49
year
a
0x4A
bar
bar
0x4E
meter per square second
m/s
2
0x55
Table 4: Unit representation
Prefix
Factor
Symbol
Notation index (hex)
none
10
–0
0x00
deci
10
–1
d
0xFF
centi
10
–2
c
0xFE
milli
10
–3
m
0xFD
10
–4
0xFC
Table 5: Prefix representation
Index
Object
Reference
0x0000
Not used
0x0001…0x001F
Data types
CiA 301
0x0020…0x003F
Complex data types (not used)
CiA 301
0x0040…0x005F
Manufacturer-specific complex data types (not used)
0x0060…0x025F
Device profile specific data types (not used)
CiA 408
0x0260…0x03FF
Reserved for further use
0x0400…0x0FFF
Reserved for further use
0x1000…0x1FFF
Communication profile area
CiA 301 / IEC 61158-5-12
0x2000…0x5FFF
Manufacturer-specific area
Moog DCV
Table 6: Structure of the CANopen object dictionary (OD)
