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.
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Is there an antenna problem with CAN Bus selectable split termination header pin?
I am trying to implement a jumper-selectable CAN Bus termination with a SPLIT configuration, as shown in this Analog Devices example:
https://www.analog.com/media/en/technical-documentation/user-...
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Compatibility and Interoperability Between CAN Standards
I'm intended to design a CAN system for a automotive scan tool. So, I need to comprise the main CAN standars used nowadays. Searching on the web I found the following options:
ISO 11519-2:1994 – Low-...
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Can RS-232 DB-9-compatible cable be used as a physical medium between two CAN bus DB-9 ports?
Note: I am not talking about connecting an RS-232 device to a CAN bus!
I am strictly interested in reusing a RS-232 cable with two DB-9 connectors (one male and one female) to connect two CAN devices, ...
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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 ...
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Can I (mis-)use a CAN bus line for phantom power?
I just looked at the datasheet of the TJA1050 CAN transceiver and noticed that both CANL and CANH tolerate -27 to +40 V.
Standards aside, does that mean I could pull the entire CAN bus to e.g. 12V to ...
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CAN Bus - Getting EOF on 6th bit of EOF
I'm debugging my robot with a CAN bus for communication between the main controller unit and all motor controllers.
Recently I'm getting several cases where I'm getting an error frame at the 6th bit ...
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Sinusoidal voltage on CAN bus signal wires when powered from 3 phase switching power supply
I am using CAN bus to communicate between this BLDC motor with a built in driver and a real-time control computer which uses a galvanically isolated Microchip MCP2561FDE/SN CAN transceiver. ...
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STM32F107 CAN software driver does not work
I am using ST drivers to use CAN bus on an STM22F107 according to the code below. It does not work. The code is as below and is available here.
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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 ...
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Using CAN bus on a NucleoH743 with Mbed
CAN bus is not working on my project. We are using a Nucleoh743 (STM32h743) programming it with mbed (Mbed OS 6.13)
I have made sure the bus is properly made, with the correct termination resistors, ...
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Is shorting two power rails with a capacitor like this OK?
I am using this CAN transceiver which runs on 5 V but, if you provide it with the microcontroller voltage on its VIO pin, then it will automatically apply voltage level correction for the micro.
The ...
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Configuring UART pins on Beaglebone Black for CAN Interface
I have been using a CAN/RS485 Cape for prototyping CAN control of a motor. I am now in the process of bringing up some custom hardware. I have a CAN Transceiver SN65HVD230D on this custom cape that is ...
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CAN Frame Malforming on Oscilloscope
I have a working 500kbps CAN bus between an Arduino Uno and a RaspberryPi. Both are connected to MCP2515/TJA1050 boards from Amazon and communicating over SPI. The RaspberryPi dumps the CAN data via ...
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MCP2551 with STM32 MCU
im learning about the CAN protocol, and bought the transceiver module MCP2551 like this:
I made the driver for CAN controller first in loopback mode for debug, im sending the numbers 1,2,3 and 4 with ...
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CAN bus traffic is destroyed for unknown reason
I am a bit stuck with connecting several STM32F405 with BeagleBone black via CAN bus.
Strange things happen when I connect 3 stm32 and 1 BB. I have checked that BB works perfectly with any ...
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Interoperability between regular and single-wire CAN bus
Is it possible to connect a regular CAN transceiver (ISO 11898-1) to a single-wire CAN bus (SAE J2411) in a compatible way? By "compatible" I mean that the whole system should support valid J2411 bus ...
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Bus interface for short distances, many device data exchange - CAN, RS485? + characteristic impedance and media capacitance
I ran into some troubles trying to design a wired bus which will connect in about 64 testing devices. My first choice of mind was CAN bus, known of it's reliability and low EMC interference. However, ...
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MCP25625 loopback mode reponse
In the loopback mode of the CAN MCP25625, if we load and send data on the TXB0 buffer, are we supposed to receive a RXB0 buffer ready and filled with data in the TXB0 buffer?
If yes, the following are ...
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STM32F429 HAL library CAN_Transmit timeout
I'm having a bit of trouble with the ST32CubeF4 v1.13.0 example of a CAN network. I'm using an STM32F429 discovery board, but I have ported over the CAN network example from the STM324x9_EVAL board. I ...
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Do you consider this design as an application layer on top of the CAN protocol?
This is a follow up question from my previous question about
How do I program 2 CAN nodes to transmit continuously in succession?
I'm planning to add another layer on top of the CAN protocol and I ...
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Hot pluggable CAN collections of devices
I'm trying to create a network of hot pluggable collections of iot devices into a bus (Containing Device 'A') that will always be present. There could be up to 50 collections with each collection ...
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CAN bus accidentally swapped TX and RX is it possible to solve (in firmware) without board rework
I am interfacing an isolated can transceiver with my microcontroller. My schematic is given below.
Accidently TXD is connected to RXD of microcontroller and RXD is connected to TXD of the ...
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No connection between the steering wheel and the AgOpen controller with CAN
I'm developing the AgOpen navigation system for a tractor and I'm having trouble connecting the controller to the Keya steering wheel via CAN bus. Everything was working fine at home on the desk, but ...
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STM32G4 brings down CAN network when exposed to electrical noise
I have a CAN 2.0 network (classic can) running at 500 kb/s. I have multiple STM32F4 nodes running the stm32 HAL CAN driver with no issues. I have another node running a STM32G4 with a FDCAN driver ...
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Debugging CAN bus
My Ford S-Max 2014 seems to have issues with the CAN bus, and refuses to start. When hooked up to Fords own diagnostic tools, it complains that the engine ECU doesn't reply. The ECU gets power, and ...
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Is a 100MHz oscilloscope good enough for SPI, UART, I2C and CAN?
I am having trouble with microcontrollers (STM32s mainly) on custom PCBs. I want to get an oscilloscope to help me solve these issues. Naturally budget is small so I want to know is if a 100 MHz ...
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Effects of baud rate / bit timing for CANBUS
I'm seeking some advice about eye diagrams for analysing node behaviour on CAN for a prototype system.
I've been given this eye diagram, which is generated using Vector's .scope Canalyser tool and ...
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Question on unshielded cabling for CANBUS physical layer
Normally, I'd advocate use of shielded twisted pair for CANBUS networks but there have been some questions recently about using unshielded cabling to achieve the same aim.
From what I can see there ...
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Sharing CAN bus to two microcontrollers without increasing bus load
I have 2 MCUs in one PCB that I want to communicate via CAN to other devices far away.
Instead of adding two CAN transceivers and becoming two node loads to the network, I thought to combine the two ...
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Orange Pi 5 CAN-bus issues
The bus-topology is like this. The CAN-bus has termination resistor at the inverter and in the Waveshare USB/CAN dongle.
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How can I use normal CAN with CAN FD?
I'm working with i.MX6ULL not supporting CAN FD but other CAN nodes supports. How can I use normal CAN on this bus without making any hardware changes?
I need to fix CAN to CAN FD communication ...
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CANL and CANH are always active
I have a Linux Ubuntu based Machine and a esp32 which both contain a CAN interface. I am also using two CJMCU-230 transreciver. The Problem is that everytime when I connect the rx and tx of the Linux ...
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Why CAN-FD trailer is different?
I created my own board based on the ATSAME70 Xplained, in order to control a sensor via CAN-FD and receive the data via USB.
I am running the same firmware in both boards, but in my version, the ...
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IWDG not stopping on debug when CAN Receive interrupt triggered
I'm having a significant problem debugging my board with CAN traffic. Whenever the debugger is paused, and a CAN message is received, the independent watchdog is being reset. As far as I can tell, I'm ...
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CAN bus incorrect frame dsPIC33FJ128MC510
I am currently trying to implement a CAN communication between a PC and a microcontroller dsPIC33FJ128MC510 (https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/...
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Issue with getting HAL_ADC_ConvCpltCallback to continuously trigger
I have STM32F0 code that reads 7 ADC channels, stores them in DMA, and transmits the values over CAN to drive a motor controller.
ADC events are triggered by tim1, then I send the CAN message in the ...
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J1939 address claim: if primary source address can not be claimed, do I need a separate DBC file for secondary source address?
I read the J1939-81 document and the following regarding the address claim procedure:
sae-j1939-address-claim-procedure
j1939-introduction
sae-j1939-address-management-messages
If arbitrary address is ...
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Protect bus and remaning bus-attached devices for bus-attached device failure (CANBus)
What are options to protect CANBus from failure of device connected to bus?
For example if CAN Transceiver pulls bus high or low. Or some other sort of electronics failure.
Thx
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The role of the VSPLIT in this CAN transceiver
I want to know how the VSPLIT (Pin 11) in the IC NCV7341 works and what its real effects in the citcuit are.
In the data sheet it says it is used to stabilise the CAN signals, but how? What does &...
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CAN BUS circuit using arduino and STM32 not receiving data
I tried to connect arduino uno R3 to STM32 using MCP2515 CAN bus transceiver. This was the transmitter code:
...
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CAN Transceiver circuit problem with TJA1042T/3
I am a novice designer who recently started designing circuits.
Using the STM32f407VGT MCU operating at 3.3V, using the CAN1TX(PB9) CAN1RX(PB8) pins, the circuit was configured by referring to NXP's ...
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why we are using 2 wired connections in can bus
I am software engineer student and I am doing researching about electric cars also how communication works in electric cars. So I was trying to find answer for,
why everyone using 2 wired connections (...
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Sending messages between CANs FD with different bitrates
In my team we are performing some CAN FD tests. We are trying to extend our current tests for classic CAN to cover FD and while trying to send message between CANs FD with different bit-rates we have ...
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Use "basic CAN" if "full CAN" is available?
From all I've read about both types my conclusion is that the only reason for using "Basic CAN" is to make message handling easier: I have to care about only one buffer.
One big drawback is ...
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How can a single CAN transreceiver be connected to two types of connectors?
I would like to connect a CAN transreceiver to the db9 connector and at the same time CAN line has to go another circuit. Is it possible to use only single transreceiver and have both access from ...
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CAN Bus Voltage Discrepancy
I’m currently using a sysWORXX USB-CANmodul1 to communicate with a Maxim MAX3051 CAN Transceiver on a custom PCB of mine. I've been having issues with the modul1 losing connectivity with the board. ...
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Canbus bit stuff Error
I was communicating two stm32f4 discovery board and i wanted to create some failure scenario to take precautions. I shorted CANH & CANL and pulled VCC, GND respectively. But now my both of board ...
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Canbus over canberry with raspberry pi two messages together at the same time
Im using a canberry with raspberry pi. Is there any way possible to send two messages at the same time with same id and be received by the other raspberry without any particular chance of getting a ...
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CANopen SYNC object and synchronous window length
In CANopen specification there is an object called Communication Cycle Priod [1006h]. This is the time interval between two consecutive SYNC objects. There is also another object called Synchronous ...
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Change operational mode of CAN transceiver
I have two MCP2515 stand-alone CAN controllers with an SPI interface, two TJA1042 CAN transceivers, and two Arduino Uno boards. As you may know, TJA1042 has two operational modes:
sleep mode
normal ...
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