Operating Instructions

CANopen Overview
CANopen Overview
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Time Stamp
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EMCY
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Boot-up
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NMT
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SDO (Service Data Objects)
Use SDO to access the Object Dictionary in every CANopen node using the Client/Server model. One SDO has
two COB-IDs (request SDO and response SDO) to upload or download data between two nodes. There is no data
limit for SDOs to transfer data, but it must transfer data by segment when the data exceeds four bytes with an end
signal in the last segment. However, the Climatix VFD does not support transferring data by segment.
The Object Dictionary (OD) is a group of objects in a CANopen node. Every node has an OD in the system, and
OD contains all parameters describing the device and its network behavior. The access path in the OD is the index
and sub-index; each object has a unique index in the OD, and has a sub-index if necessary.
Type
Data 0
Data 1
Data 2
Data 3
Data 4
Data 5
Data 6
Data 7
7
6
5
4
3
2
1
0
Index
Index
Index
Data
Data
Data
Data
command
L
H
Sub
LL
LH
HL
HH
Domain
Download
Client
0
0
1
-
N
E
S
Server
0
1
1
-
-
-
-
-
Domain
Upload
Client
0
1
0
-
-
-
-
-
Server
0
1
0
-
N
E
S
Abort Domain
Transfer
Client
1
0
0
-
-
-
-
-
Server
1
0
0
-
-
-
-
-
N: Bytes not used; E: normal (0) / transferred (1); S: data size
PDO (Process Data Objects)
PDO communication can be described by the producer/consumer model. Each node of the network listens to the
messages of the transmission node and distinguishes whether the message has to be processed or not after
receiving the message. A PDO can be transmitted from one device to one another device or to many other devices.
Every PDO has two PDO services: a TxPDO and an RxPDO. PDOs are transmitted in a non-confirmed mode. All
transmission types are listed in the following table.
Type Number
PDO
Cyclic
Acyclic
Synchronous
Asynchronous
RTR only
0
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1–240
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241–251
Reserved
252
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253
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254
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255
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