CAN stands for Controller Area Network and is a bus often used in automotive applications.
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Sending CAN protocol data(1Mbps) via serial port
I would like to build a tool for viewing CAN protocol data on my computer. The CAN protocol data is captured using a microcontroller (STM32F4 discovery board) and sent to a PC via a serial port. My ...
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3answers
92 views
TXERR error in CAN communication
I tried CAN communication using PIC18F25K80 and MCP2551. Using two
nodes, I could transmit data from one node to other. But, data was transmitted only when the receiver buffer was set to ignore all ...
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1answer
105 views
Selecting communication between microcontrollers at high temperature
I have been assigned to a project to find the best possible communication between several PCB boards which have microcontrollers for a specific function. I need to have all microcontrollers ...
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2answers
157 views
CAN Transmission and termination resistors
I have been trying to set up a CAN network using PIC18F25K80 microcontrollers and an MCP2551 to communicate between them. Can I use two simple wires as a CAN bus by just connecting the CANL, CANH of ...
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1answer
201 views
Can I remap a car\bike ECU using CAN bus?
I am thinking to use something like this to connect an Arduino to a motorbike engine control unit (ECU): Arduino CAN-Bus Shield with uSD Card Holder.
I never did something like this; using CAN bus, ...
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2answers
136 views
Best microcontroller electrical bus for high speed synchronized sampling from slaves
I have an application which requires that I sample a dozen of sensors for each node and transmit the data to a master microcontroller in regular four second intervals. The surface area of the sensors ...
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3answers
442 views
Correct place to attach shields for twisted pairs
I have two PCBs connected by a cable containing 5 sub-cables:
6v power through a custom made coaxial cable (similar to that found on laptop power supplies).
2x 100mbps LVDS through 100ohm impedance ...
4
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1answer
205 views
CAN bus bit timing with 16 MHz crystal
I'm trying to receive CAN messages from a radar, whose specification define the following data for bit timing:
...
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1answer
118 views
Coax cable with CAN bus
I got some Microchip CAN transceivers and some Stellaris Launchpads from TI. I would like to learn how CAN works. It looks very nice for what I want to do (one controller per room, controls lights, ...
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Why does the CAN bus use a 120 ohm resistor as the terminating resistor and not any other value?
I know the reasons for using terminating resistors on a CAN bus and how important it is.
But why 120 ohm? How did this value come up? Is there any specific reason to use 120 ohm?
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2answers
472 views
1-wire verses CAN-bus for home sensing network?
I'm trying to put together a home automation solution for my newly built house. I'm very new to this, specifically for hardware matters and asking this question to verify if my understanding of what ...
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3answers
290 views
Most efficient way to handle addressing / termination in a daisy-chained CAN bus?
I'm working on some devices that will talk to each other over CAN. The simple idea is to daisy chain essential signals between each device: power (+12V and ground), enable and CAN high / low.
Now, ...
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2answers
121 views
Packet loss in CAN
How susceptible is a CAN bus to packet loss, and what are the sources of packet loss in CAN?
I realize the answer may depend heavily on the application, so here are some details:
bus length: about ...
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5answers
343 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 ...
4
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1answer
139 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.
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2answers
229 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 ...
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2answers
497 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 ...
2
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1answer
306 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 ...
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2answers
204 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 ...
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2answers
157 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 ...
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1answer
161 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 ...
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1answer
155 views
CAN module in STM32F207 - continuosly transmitting the same message
I have configured the CAN module in STM32F207 to transmit at 1 Mbit/s. The program is such that it will transmit the same CAN frame for every 2 msec. I observe that even if the code is not ...
2
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2answers
271 views
CAN Baud rate configuration - STM32F207
I need to configure the CAN Module of STM32F207 to different baud rates of 500 kbit/s, 600 kbit/s, 700 kbit/s, and 1 Mkbit/s. For 500 kbit/s and 1 Mkbit/s I am able to ...
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1answer
172 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?
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4answers
2k 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 ...
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4answers
2k 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 ...
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3answers
860 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 ...
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1answer
435 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 ...
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0answers
305 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 ...
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1answer
931 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:
...
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2answers
801 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 ...
4
votes
3answers
1k 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 ...
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3answers
434 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
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3answers
1k 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 ...
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1answer
1k 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. ...
4
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1answer
208 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 ...
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4answers
671 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 ...
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3answers
649 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 ...
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1answer
240 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 ...
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2answers
594 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 ...
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3answers
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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 ...
