All Questions
39
questions
0
votes
1
answer
79
views
How may I manually construct CAN message for CANopen?
I understand CANopen uses CAN, the difference is usage and message type. I have basic CAN capable device and I want to control industrial motor controller, which uses CANopen.
I have its EDS file, but ...
- 1,039
0
votes
0
answers
41
views
Logging CAN bus load over time
I have used CANKing, which displays the bus load in real-time. However, I would like to do some long-term monitoring to see what the load looks like over time.
This site claims to have free software ...
- 121
0
votes
1
answer
126
views
STM32 Can bus random data
I am using an STM32 to transmit data over CAN using CAN2. Currently, my code is only setting up the can peripheral and sending periodic messages.
My messages usually look like this on the receiving ...
- 49
2
votes
1
answer
789
views
Consumer heartbeat time configuration in CANopen
I have the following situation. I have a master (consumer) and a slave (producer), the slave has to be between nodes 1-127, in this case the slave is in the node 125.
I'm trying to syncronize both of ...
- 21
0
votes
1
answer
150
views
CAN-Bus Message confusion
Can anyone tell me what the difference between these two sets of CAN Bus messages? This is from the manual of a Power Drive Unit (PDU) in the Cargo Handling System of a 747F (UPS Freight). This is the ...
- 41
0
votes
0
answers
69
views
ID collision on CANOpen SDO
I am working on a remote control module to control my heating boiler remotely. The boiler uses CANOpen 125k.
My module transmits periodically SDO requests to read temperatures and other parameters. ...
- 11
1
vote
1
answer
77
views
CAN physical layer flexibility
I'm considering designing a CAN bus (CANopen) where part of the bus, closest to each node, does not use twisted pair. Partially the bus will run in a DSUB, but partially through stackable header or ...
1
vote
2
answers
3k
views
Can CANopen coexist with CAN2.0B on the same bus?
I am new to CAN protocol so I have questions about combinations of CAN-Bus nodes on same network:
Is it possible to communicate with two different devices one having CAN in Automation (CiA) CANopen DS ...
- 530
0
votes
0
answers
411
views
CANOpen SDO block transfer retry if timeouted?
I'm using the CanFestival CANOpen library (https://canfestival.org/) for a PC app that talks to a device via CAN bus. The device is CIA-301 compliant. I'm using SDO block transfers for device firmware ...
- 125
2
votes
0
answers
164
views
Best approach to program a PLC using dbc file? (CAN communication)
I'm pretty new using CAN Communication but I need to program a Phoenix Contact PLC in Structured Text. The PLC should communicate with a motor that uses CANOpen protocol. The only resource I have is ...
- 21
3
votes
0
answers
652
views
Home automation using CAN bus
I am planning to make a prototype for wired home automation devices, and I am thinking of using CAN bus for communication between nodes and Gateway.
The way I am planning to build it, there is one ...
- 31
3
votes
1
answer
582
views
Different CAN-BUS specs on the same bus
I have several questions about different combinations of CAN-Bus nodes that are able to work together with realiability:
CAN2.0A and CAN2.0B nodes can work on the same bus at the SAME speed?
CAN2.0A ...
- 31
1
vote
1
answer
542
views
Multiple CANOpen SDO requests "in the air" at once
In CANOpen, expedited SDO requests and responses include the index and sub-index of the request.
All CANOpen master implementations that I've looked at require only one SDO per device be sent at once, ...
- 113
0
votes
0
answers
636
views
Transmit and receive in PDO for CANopen - Why use transmit channel?
According to CiA 301, there is something called TPDO Mapping and TPDO Communication.
TPDO communication is used for describing ...
- 1,324
2
votes
3
answers
2k
views
Process Data Objects - CANopen - How do they work?
I'm searching for information about PDO and the protocol CiA 301 V4.2.0 at topic 7.2.2.5.1 does not exactly show how PDO's work. ...
- 1,324
1
vote
2
answers
945
views
When should I use normal SDO transfer in CANopen?
CANopen have two types of methods for transferring and receiving data between server and client.
Expedited mode = Send fixed bytes (maximum 4 bytes)
Normal mode = Send maximum 7 bytes at the time
If ...
- 1,324
0
votes
1
answer
239
views
Peer to Peer in CANopen - How does it work?
CANopen have something called an 11 bit COB-ID, it contains function code of 4 bits + node ID of 7 bits. For example:
Image from here.
Does this mean if the MASTER send a request to the CLIENT for ...
- 1,324
1
vote
2
answers
283
views
Why are NMT masters acting as SDO clients and not SDO masters in CANopen?
According to CSSeletronics.
What is the SDO service?
The SDO service allows a CANopen node to read/edit values of another
node's object dictionary over the CAN network.
As mentioned under '...
- 1,324
0
votes
1
answer
2k
views
What does Reset Node and Reset Communcation do in CANopen?
According to NI, NTM commands can be sent to the Node. They are the follwing:
Start Remote Node
Stop Remote Node
Enter Pre-Operational
Reset Node
Reset Communication.
Start Remote Node enables all ...
- 1,324
0
votes
1
answer
371
views
Sending raw data with CANopen - Which function/COB should I use then?
I want to send raw data with CANopen. Which COB-ID should I use then?
My goal is to transmit for example an array of X bytes and when the receiver got that array, it going to understand how to ...
- 1,324
0
votes
1
answer
6k
views
Modbus Vs CANopen - Which one should I choose?
Modbus Vs CANopen - Which one should I choose if I want:
Broadcast to all units
Talk to specific units
Robust
Send lots of data
Implement for embedded systems
Easy to use
Using in new projects with ...
- 1,324
0
votes
1
answer
1k
views
How can 3.3v CAN-bus transceiver communicate with 5 volt CAN-bus transceiver?
I'm suing TCAN33x from Texas Instruments and it's a 3.3v CAN-bus tranciever.
I have succeed to listen for CAN-bus messages from a 24V J1939 CAN-bus stepper motor. Very industrial.
But I haven't ...
- 1,324
1
vote
1
answer
7k
views
CANopen - explanation of TPDO and RPDO
I am working on a project that uses the CANopen protocol. I have a problem with understanding the use of TPDO and RPDO. In some articles, RPDO is described as a request calling TPDO from another node, ...
- 73
0
votes
3
answers
2k
views
M8 connectors and their coding
A quick read on the internet shows that M8 connectors are coded.
The little info online I can find says A-coded is the most common style, typically used for sensors and actuators. B-coded is is mostly ...
- 757
1
vote
1
answer
291
views
Reading multiple CANbus outputs with one controller
my encoder has a CAN communication interface. I need 4 encoders for my application. However, my controller only has 1 CAN communication interface.
Assuming, the encoder has different CAN ID, will it ...
- 145
1
vote
1
answer
1k
views
Power Supply issues with CAN bus
I am currently working on a system using C# for a windows GUI with an Ixxat USB-to-CAN and an STM32F303K8 that runs CANopen, The system itself is running fine I can send and receive messages to and ...
0
votes
1
answer
763
views
PCB layout for CAN bus transceiver
I have a PCBA where the connector for the CAN bus is about 40 mm away from the MCU. The MCU and connector positions are fixed but I am free in placing the CAN transceiver.
I haven't worked with CAN ...
- 757
1
vote
1
answer
62
views
Do i need additional IOs for this interface board?
I am designing a UI PCB which has an MCU which will interface with a main system controller (MSC) on a separate PCB.
The UI PCB provides an initial power up to the MSC which then boots up its onboard ...
- 757
0
votes
2
answers
841
views
CAN bus communication. Issue with two slaves having same CAN ID
Does anyone know if it is possible to have CAN offsetting in case two slaves in same circuit transmits different data in same ID?? I have two slaves with same CAN ID transmitting data and I cannot ...
0
votes
2
answers
446
views
Is it possible to map pre defined data sets in PDO Mapping of CANOpen protocol
I've been trying to learn about CANOpen protocol and create a slave device accordingly.
I understand that PDO mapping can be either static, or fully dynamic (according to CIA-301).
My coding skills ...
- 3