Questions tagged [can]
CAN stands for Controller Area Network and is a bus often used in automotive applications. It is a two-wire differential protocol and works on baud rates from 10 kbits/sec to 1 Mbits/sec.
838
questions
3
votes
5
answers
10k
views
Is CAN bus communications enough to update firmware?
I am going to control a few microcontroller-based units (approximately 30) from a master computer.
They are going to be connected using a CAN bus
The furthest lying unit may be approximately 10 meters ...
- 31
4
votes
1
answer
1k
views
CAN controller in a CPLD
As I cannot manage to find it done on internet, I wonder if it is possible to program a CAN controller in a CPLD ? It's look like it is going to require a least an FPGA.
- 805
14
votes
3
answers
13k
views
Transmission of different messages with the SAME ID on a CAN bus
CAN arbitration is done with IDs, and any node on the bus can transmit with any ID (ideally it should not, but a nasty node can).
What if two different nodes connected on the same CAN bus transmit ...
- 3,275
3
votes
2
answers
5k
views
CAN bus system causing me extra work!
I bought a car reversing sensor system... I bench tested it with a simple 12 V PSU, and it works great. Integrating it into my car is another matter since finding out that most cars since 2008 ...
- 31
3
votes
1
answer
3k
views
CANopen frame format?
Is there a resource that describes how CANopen frames are constructed down to the byte level?
I'm trying to decode a hex dump from a CAN bus, see the image below. The high-level CAN messages that ...
- 1,647
4
votes
2
answers
7k
views
CAN driver - error passive state
I have a device based on TMS470R1B1M from which I try to send CAN standard frames every second. As soon as I turn on the device, the device enters the error passive state.
How do I handle this error ...
- 163
2
votes
2
answers
289
views
CANopen protocol
If a CANopen device is said to be CANopen compliant (for example, compliant to DS 301), is the criteria for saying it to be compliant only based on the Mandatory Object Dictionary Entries supported or ...
- 163
1
vote
2
answers
1k
views
What is a multiplexed network?
What is a multiplexed network?
Multiplexing means many to one and sending the result over the network. As far as I know, Control Area Network (CAN) supports multiplexing. How?
CAN is said to support ...
2
votes
1
answer
789
views
CAN module in STM32F207 - continuously transmitting the same message
I have configured the CAN module in a STM32F207 to transmit at 1 Mbit/s. The program is such that it will transmit the same CAN frame for every 2 ms. I observe that even if the code is not ...
- 163
5
votes
2
answers
13k
views
CAN Baud rate configuration - STM32F207
I need to configure the CAN module of a STM32F207 to the following different baud rates: 500 kbit/s, 600 kbit/s, 700 kbit/s, and 1 Mbit/s. For 500 kbit/s and 1 Mbit/s I ...
- 163
1
vote
1
answer
338
views
CANopen Protocols
I have a CANopen slave stack. Is it possible to implement both the CANopen master and slave functionalities using the same stack? Or is a separate master stack required?
- 163
12
votes
3
answers
26k
views
Is MCP2551 a UART-to-CAN converter?
I want to make a CAN bus sniffer for 250 kbit/s using my computer. After some research I've found that MCP2551 is some kind of voltage level regulator for CAN's physical layer. Keeping that in ...
- 831
53
votes
5
answers
42k
views
Is a CAN enabled microcontroller sufficient to drive a CAN bus?
There are a number of CAN modules built into microcontrollers these days. The PIC18F2480 is an example of that. Is that microcontroller (with built-in CAN) capable of driving a CAN bus on its own or ...
- 12k
8
votes
3
answers
8k
views
Why won't my CAN transceiver receive messages unless there is a long startup delay or a bus analyzer connected?
I am using a 16-bit MCU, PIC24HJ64GP504, to write a CAN based application. Basically it is communication between my board and one another node which continuously keeps on sending data to my board ...
- 81
7
votes
1
answer
3k
views
Multiple devices on a CAN bus via the OBDII diagnostic connector in car
We have an aftermarket cruise control installed (in Suzuki Swift), which is connected to the OBD-II connector to access the CAN bus (according to the installation manual, it uses just CAN-L and CAN-H ...
- 473
2
votes
2
answers
2k
views
UDS with more than eight bytes
The unified diagnostic services (UDS) protocol in ISO 15765-4 seems to be specifically designed for bus systems with a message length of eight bytes (for example, CAN). Now, new transport layers like ...
- 121
3
votes
2
answers
4k
views
My code tries to configure the CAN device, but it never leaves configuration mode. Why?
I'm using a PIC32MX534F064L, and I just started working with the CAN module. The first thing I tried was using the examples from Microchip. None of them worked. The basic problem is these lines:
<...
- 253
7
votes
2
answers
3k
views
What does this CAN bus waveform mean?
I am trying to get the ECAN functionality working on a dsPIC33. I have two identical dsPIC33s, each with identical CAN transceivers connected by a short (3 inch) bus. One is transmitting, one is ...
- 27.5k
14
votes
4
answers
10k
views
Implementing a CAN protocol layer in software
Background
I'm developing a project which will require the modest microcontroller specs of:
8 12-bit, 10kHz ADCs
1kB of RAM
48-QFN or smaller footprint
20kbps daisy-chainable noise-resistant and ...
- 20.1k
3
votes
4
answers
3k
views
Where can I get CiA 302, CiA 304 and CiA 305?
Where do I find the following CANopen documents?
CiA 302
CiA 304
CiA 305
- 831
2
votes
3
answers
3k
views
CAN bus terminal
I have a CAN bus network that I want to test. I want to send CAN messages over my computer and see the responses. I have a Microchip kit with CAN that sends the responses over USB Mini and can be read ...
- 831
5
votes
1
answer
5k
views
Running a CAN sample project on LPCXpresso LPC11C24
The LPC11C24 has a on-chip CAN transceiver and a section of ROM with CAN driver software. I am trying to run the can_onchip sample project on the LPCXpresso board. ...
- 511
5
votes
1
answer
282
views
Developer/application board with a CAN/SD card
We have to develop a data logger. I should get some data over CAN (1 MBit/s), compress this data and save it to an SD card. To save time, we would prefer to use as much existing hardware and ...
- 153
9
votes
6
answers
10k
views
How to check the CAN bus is free or not
I read a lot of stuff regarding CAN bus arbitration, but it didn't answer my questions.
If one node is already transmitting the data on the bus and in between another node wants to initiate the data ...
- 3,275
7
votes
3
answers
3k
views
GND difference between CAN nodes?
I am running a short (2 m) CAN bus with about 20 nodes. 1 Mbit/s speed, PIC 18F2580s and 18F4580s with MCP2551 transceivers, 10 MHz (with PLL to 40 MHz) crystal oscillators. Both ...
- 27.5k
3
votes
1
answer
327
views
MCF5253 CAN controller transmission problem
I am using the MFC5253 controller. It has two CAN channels, CAN 1 and CAN 2. In my project, I am using both of them. Their registers are the same, except for the name (1 and 2).
I can transmit and ...
- 3,275
2
votes
2
answers
1k
views
Debugging a LPC23XX based CAN bus sniffer
I am trying to get a CAN bus sniffer working, based on LPC2368. I keep getting a bus error interrupt, of type "form error". I suspect my timing settings. I verified that the sending party is ...
- 266
10
votes
3
answers
2k
views
Selecting a network layer over CAN bus
I am planning on using CAN bus in an industrial automation application, however I'm having a hard time deciding how to implement the network layer. Does anyone here have any recommendations for a ...
- 3,899