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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Convert RS232 signal to I2C/CAN/MAVLink signal
I have an airspeed sensor that outputs a RS232 signal: https://www.aeroprobe.com/micro-air-data-system/. I want to connect this sensor to the Pixhawk in order to use the data for my controller ...
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Can CANBUS wires be used in same cable as 12V
I mean a multiwire cable - with four separate wires put into single isolated cable like this. Two would be for CAN, one for 12V and another for -12V (GND). Would it cause interference? Or would it be ...
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RS485 to CAN transceiver converter
I am using an ESP32 that has a CAN transceiver on it. I want to be able to communicate with an RS485 device.
Below is a block diagram of the high-level schematic for this:
Can someone assist with ...
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K-Line vs CAN bus
I'm building an app (running on a Pi) that will communicate with consumer vehicles for diagnostics and control. I assumed that I could achieve this over CAN bus since all vehicles after 2003 are ...
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No CANbus response to broadcast
I am trying to create a simple OBD tool in Linux to talk to my car (2009 Honda Accord). My OBD device successfully connects and I see lots of CAN frames arrive. However, when I issue an OBD command (...
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STM32 CANTX line always idle
I'm trying to learn about microcontrollers in general and at this point I'm trying to learn about the CAN bus standard by using it with an STM32 MCU in a NUCLEO-F767ZI board.
For that end I want to ...
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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 ...
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Twisting four CANBUS wires (High, Low, GND, PWR)
From what I understand, the High/Low CAN wires must be a twisted pair and it seems like a bad idea to create a 3-wire braid with the High/Low along with the GND wire, let alone with PWR.
Just to be ...
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BOSCH CAN 2.0 with ISO 11898 High Speed CAN
I'd like to use the PIC18F25K83-E/SS micro controller with the TCAN332 transceiver to implement a CAN node. In the PIC documentation it specifies the BOSCH CAN 2.0 standard while the TCAN322 specifies ...
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STM32 CAN-bus: Mail boxes are full and gives HAL_CAN_ERROR_PARAM back - Change parameters
I have two STM32 microcontrollers and they have CAN-bus connection with each other.
The problem is that when I connect them together, then the transmitter will after a few messages, stop transmitting ...
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STM32 how to test CAN interface without a transmitter connected?
I'm doing some work on STM32 board, and I don't have a CAN transceiver connected to my STM (yet). CAN_RX / CAN_TX pins are just hanging in the air. Is it possible to at least test the loopback mode in ...
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Could I Test CAN Tranceiver with External Loopback Mode?
Hello I am using STM32H753 over a custom PCB. I have no any CAN Analyzer except oscilloscope, multimeter and logic analyzer. We have a problem with CAN BUS communication. I am suspecting of CAN ...
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Best desoldering technique for reverse engineering, or maybe UART
So I'm trying to play with an EPS motor. I was able to get it to this stage while still functioning (can bus still alive and motor spins), but I want to see what processor is uses and see if I can ...
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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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CAN controller with UART interface IC?
Recently I have new request to add CAN interface for communication, but there is no CAN interface in current MCU. Then I found I can add a CAN controller with SPI interface to achieve.
My question is ...
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Is this design of a motor controller valid?
I am trying to design a compact robotic actuator. My main focus with this project is to reduce the amount of external wiring needed to do with robots. With that in mind, I have thought of the ...
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VDD pin is opposite from GND pin. Which layout is more effective for decoupling and grounding?
I am aware of some basic goals of a decoupling and grounding layout: Reduce EMI by minimizing overall power-GND high-frequency current loop area, minimize ground inconsistency by reducing impedance to ...
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Are my PCB and schematic OK? Am I missing something?
this is my first time designing and ordering a PCB, so I'm quite nervous about this. So I thought you guys could have a look, since you are more experienced than me by far.
The PCB is for an ...
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What is the exact type of this common mode choke?
I have this(on the picture) element missing from my PCB but I cannot find the exact model and specification.
The text on it says G8276D3. Can somebody recognize it?
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Why are capacitors and resistors commonly used with CAN High & CAN Low lines?
I often see resistors and capacitors connected to the CAN high and CAN low lines but in my experience, communication between nodes is still functional without these components. Can someone please ...
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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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How can I design a CAN BUS hardware interface for STM32? (TTL and CMOS issue)
I am designing a PCB based on STM32F446 and I want to include CAN BUS communication. I know I need a transceiver (from CAN_H and CAN_L to TX and RX) and a CAN Controller. I have thought about MCP2551 (...
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Why does CAN dominant signals override recessive signals?
I am studying how the CAN standard works and I am unsure how the voltage works in the system. I know that a recessive signal is a 1 and is represented in a 5V configuration by ~2.5V where the voltage ...
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STM32 CAN bus silent mode
I need to use the CAN bus simply to receive frame data (i.e. not transmit.)
Can I use it in silent mode?
I know that the main limitation of this mode is the fact that it does not transmit, so no ...
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LIN interface INH pin
What would happen if I pull down the INH pin of this IC to GND?
I am unable to understand what would happen if I pulled to GND or make it HIGH?
Can someone help me ?
user220456
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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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ESP32MINI + MCP2221A + 3.3v, 5v, and 12v power supply circuit problems
I'm trying to design a circuit with an ESP32-Mini that connects to a CAN bus via an SN65HVD230. I've added an MCP2221A as a USB/UART interface to the ESP32 so that I can program the chip while on ...
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What is the purpose of the resistors and capacitors in this CAN interface circuit?
I am trying to understand what these resistors and capacitors (R66, R70, C76) and (R73, C75) doing in this circuit. They don't seem necessary to the function of the circuit.
Any idea on what function ...
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Possible that some CANbus message are eaten?
I am developing a firmware update via CANbus 2.0B.
The client is written in python to send the firmware binary file to the receiver (an esp32-based custom pcb equipped with a CANbus transceiver). The ...
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Capacitive Signature on CAN Bus Driver SN65VHD230
I'm working on a small custom PCB that uses the TI SN65VHD230 CAN Transceiver and the square waveforms of the CAN bus aren't as clean and crisp as it seems they should be.
I have a 10 μF MLCC on the ...
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