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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Datalogger - Multiple CAN Bus
I have around 15 CAN Bus Interfaces (not connected to each other) sending data on the bus abd I want to read all the data and forward to a PC (via USB or Ethernet).
I have looked into MCP2515. I will ...
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Make CAN-bus connection as netif interface (LWIP) [closed]
I want make network connection between 2 STM32F407 by CAN-bus protocol (without use physical Ethernet RMII/MII). Could you help me how can i do this? I think I have make CAN connection as netif (...
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5V CAN transceiver (TJA1040) with a 3.3V uController (ESP32)
I'm designing a CAN node using an ESP32, which works on 3.3V. The only transceiver I can find where I live at a reasonable cost is the TJA1040. The datasheet says it works both on 5V and 3.3V. I am ...
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Request for Review: First PCB Design - Feedback on Potential Issues or Missing Elements
I have recently designed my first PCB and I am seeking feedback on it to ensure there are no errors or missing elements. I have attached the schematic of my design. The PCB includes various components ...
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Swapping CANH and CANL kills my power converter
I got the first set of these CAN boards I designed and I plugged one into my test setup consisting of a two CAN dev boards as seen below. The first time I plugged my board in I didn't realize I had ...
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CAN Transmission not going through
I have a CAN bus set up, my two nodes are the STM32-F429ZIT dev board and a raspberry pi with RS485 CAN hat. I am trying to transmit from the STM32 to the raspberry pi. When I try to run this code, ...
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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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How do I convert an I2S/TDM signal to a CAN signal
I'm getting output from the Analog Devices ADXL317 and I want to convert the output signal to a CAN signal. I don't think many CAN transceivers can take input from the I2S bus, so I need to find ...
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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 ...
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CAN BUS Chassis Grounding
Hoping to get get some guidance on correct grounding for a CAN Bus I have designed. The following diagram gives a high level overview of the system connectivity:
Some notes on the setup:
There are a ...
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UART communications using CAN bus differential signalling
I need to interface with a device that talks UART, but with CAN bus signalling. Here's a picture where a tester (which I want to replicate) talked to that device:
While RS485 seems similar, the ...
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How does CAN transceivers output CANH=3.5V and CANL=1.5V? [duplicate]
This is a questions that has been asked but did not find a clear answer. How it is the 3.5V achieved on CAN_H? Assuming there is 0.5V voltage drop on the internal diode, 0.1V on the internal MOSFET ...
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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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Add or remove 120 Ohm from the CAN circuit using Microcontroller
I want to design hardware circuit using microcontroller for CAN communication. One suggestion i require is i want to add 120 Ohm or remove it based on software configuration. I want to close the ...
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Adafruit Feather M4 CAN Express overvoltage protection
I would like to read CAN signals from my car over the OBD-II connector.
My question is, whether I need to implement any kind of (overvoltage) protection, so the Adafruit won't get harmed (and vica ...
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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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CAN Protocol traced routed with 90 ohm characteristic impedance
I am using ISO1042BDWV in my board. The schematic is given below. I know that the characteristic impedance of the CAN bus is 120 ohm.
The layout team routed CANH and CANL as 90 Ω differential. The CAN ...
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Powering LED from a CAN bus signal
I am looking for a can it be done and, if someone is willing, a how to.
I am building an OBD2 breakout box for easily scoping automotive computer data lines and want to add LEDs as a quick visual of ...
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AT32F403AVGT7 how to set CAN baud rate for this controller
I am using AT32F403AVGT7 controller but I am not getting any CAN response due to incorrect baud rate. Does anyone know how to set baud rate for this controller? I will share my code below:
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What can cause these CAN signal distortions?
I occasionally observe signal distortions on CAN H, CAN L, and so also the differential signal. It is causing the microcontroller (dsPIC33) to report so-called Invalid Message Receive (IVR) errors. ...
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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 ...
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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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RS485 to CAN converter
I want to design where a RS485 Device Sensor reads inputs and the information it reads and sends is converted to CAN (Arduino UNO R4 Minima with CAN built in, or ESP32 with CAN built in)
Is this ...
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Is there any way to get a smaller SPI clock speed specifically to only one SPI slave?
I have 3 modules connected by SPI through an ATMEGA328P MCU as shown in the circuit and I have some doubts over the clock speed of the bus.
I have a 8Mhz clock on the MCU which I am assuming sets the ...
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I am using Halcogen to generate LLD for TMS570LS0914. But it seems like there are only 64 Message Objects for each CAN channel
I am using Halcogen to generate LLD for TMS570LS0914. But it seems like there are only 64 Message Objects for each CAN channel.
Q1. How to transmit/receive more than 64 CAN messages on single CAN ...
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Resolving CAN Communication Issue: Decoding and Fixing 'BUSPASSIVE BUSWARNING'
I set up a communication system (J1939) using two MCP2515 modules connected to two Arduino UNO boards. Then, I added a PCAN USB interface to monitor messages using PCAN View Software. Everything was ...
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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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Is external ESD protection needed with the MAX3051?
I'm currently doing my first Project using custom PCBs.
It's a CAN based system to control things around my house (lights, blinds, sound, etc.).
I'm planning to use multiple STM32F103C6 (in Form of a ...
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CANbus wiring architecture
I'm building a multi device using canbus for communication and have a few questions.
The image below illustrates my setup with multiple canbus wiring possibilities for devices. The big pcb called MAIN ...
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