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 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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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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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 ...
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What's the maximum CAN bus frame (message) rate at 125 kbit/s?
My CAN bus is running at 125 kbit/s and is using extended frame format exclusively. I would like to know what's the maximum rate of CAN frame I can send out. Suppose the data length is always ...
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Why do microcontrollers always need external CAN tranceiver?
For example in STM32 MCUs, the CAN pins are CAN RX and CAN TX. Therefore to transform it to CAN H and CAN L, we need to use external CAN tranceiver. What's the purpose of it? Wouldn't it be easier to ...
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CAN Bus Licensing
Looking around for possible solutions for long distance communication between multiple microcontrollers I found the CAN bus. However, it says that there is a licensing fee for any implementation of ...
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Significant differences between CAN and RS485 regarding the physical layer
In comparing the physical layer of CAN and RS485, I am trying to find the advantages of either one over the other. I found out that they are quite similar. Both are good in terms of common mode ...
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What is the color code for CAN Bus?
I would like to know if there is any color code specified for CAN Bus communication wiring, maybe in ISO-11898-1? (I have no free access to the file)
I looked for any official documents without any ...
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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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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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Is a ground/common needed for proper CAN bus communication?
Since CAN Bus is a differential signalling system, what is the significance of GND/COM signal? Can I get by without it?
I've got a very simple 2-node system that has some weird happenings going on. (...
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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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CAN bus signal integrity
The channels are CAN_H (red), CAN_L (blue), and CAN_H-CAN_L (brown).
It can be observed in the diagram below that CAN_H-CAN_L has an acceptable signal shape. However, both CAN_H and CAN_L look poorly ...
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Enable interrupt but no ISR
I would like to know what happens if an Interrupt is enabled(ex:Arbitration Lost Interrupt in CAN module of NXP's LPC1778),but no ISR has been defined for the interrupt.
When such an interrupt occurs,...
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What exactly is "dominant" and "recessive"?
I am reading data sheets on the LIN bus, but apparently the same terminology is used for CAN.
What does "recessive" and "dominant" stand for, e.g http://hw-server.com/products/rs_optika/...
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