CAN interview questions

My complete course on CAN LIN AUTOSAR, click the below 80% discount coupon link
www.udemy.com/...
Interview questions on CAN communication protocol

[@VenkateshMane]

for complete course on CAN LIN AUTOSAR www.udemy.com/course/can-and-lin-communication-protocols/?referralCode=F50CFD8FA492E1693415

[@bhanuprakash-lj3lc]

Its not giving the discount at all sir. Its at full cost

[@MegaUmadevi]

Wow great explanation sir. I was your student at BVBCET for the elective Automotive electronics. Now it feels so good to watch these videos to brush up the topics. :)

[@ghanshyampawar8627]

Very useful questions answered 👍

[@2flyingbirds293]

खूप छान सांगितलं सर

[@manju3e]

Super explaination sir.. thank u sir..

[@VenkateshMane]

Thank you

[@jdeep0709]

Informative video 🙏

[@terryshi2010]

Thank you for your video and i believe it's a great video by those positive reviews, howeven i could not understand anything.

[@VenkateshMane]

I am sorry to know that, keep watching again and again you may get it

[@thinktalk9250]

Very informative useful info thanks

[@danielaesmaili2391]

Very useful for interviews. Thanks for sharing

[@saraswatihulagannavar5630]

Really helpful sir thank you sir

[@kuruvasudhakar9210]

Very nice sir

[@VenkateshMane]

Thank you

[@ranjithreddy2715]

Thank you so much for the video, but I feel this information is so useful for the ones who is very new to CAN protocol, however this video is not giving in detailed information for the ones who is already have knowledge on this. Please if possible can you provide more details like below 1) Why we need to give 3.5v and 1.5v for dominant. 2) What is overload frame means 3) More explanation on fault confinement, like what are the tx and rx counters for error active, error passive and bus off condition. 4) How the bus off condition will occur. 5) Different types of error frames etc.

[@satya_kartik8795]

It's very useful knowledge sir, but you could better explain with written answers. Because some terms i couldn't understand.

[@asharanic5429]

Hi sir, Thanks for sharing the knowledge.its really helpful video. Please address my questions: 1. How to trigger bus off state and how to check the bus off state in Caneo/CanAnalyzer? 2. What will impact, if NRZ concept is not used in CAN? 3. Difference Between CAN and CAN-FD it's applications. - Thanks

[@VenkateshMane]

Ok I will try to address in my next video

[@shankarm3548]

Great sir...Thank you

[@naveendubey4412]

Wow! Excellent explanation.This is the best youtube platform I have got to learn. This is my first video watching in this channel got massive knowledge from this. Feeling so much regret why I didn't get to know about this before.

[@VenkateshMane]

Thank you

[@kiranshashiny]

What's the difference between CAN Controller and CAN Transceiver ? I'm using Arduino+MCP2515 CAN controller as a SENDER at one end. and Arduino+MCP2515 CAN controller as a RECEIVER at the other end. So I have connected a piece of wire to CAN Controller "H" of sender to "H" of receiver, and likewise "L" to L" of the receiver. and it's communicating now. How is it working without the transceiver !

[@VenkateshMane]

It mcp2515 has both controller and transceiver

[@VenkateshMane]

CAN controller runs protocol part, transceiver is just a voltage converter from ttl logic to can bus logix

[@kiranshashiny]

Thanks for replies. 1. Where does the MCP2551 come in? 2. Can I configure communication between two nodes with just the 2515 and have them communicate over 2 wires 'H' and "L" ?

[@VenkateshMane]

@@kiranshashiny you would also need microcontroller, which is arduino in your case

[@juniormarvel9612]

Sir pls make video on automotive ethernet and its interview questions

[@sreedharm2600]

Superb 👌

[@raghudm5975]

Nice Master

[@kakhil1843]

bro ur iit student. ur explanation is very good bro

[@VenkateshMane]

Thank you so much 🙂

[@Rajkumar1010]

Thank you .. easy to understand

[@mohammadarifkhanies819]

HI SIR CAN YOU PLEAS PROVIDE UDS INTERVIEW QUESTION AND CAPL ALSO

[@VenkateshMane]

Sure i will do it

[@venkateshkarlapudi3441]

What is 'synchronization' in CAN?

[@abouttheravadabuddhism]

I can hear enough to know its an excellent tutorial, but even after having been married to an Indian for 13 years and attending countless Indian events in the US, I still can't understand what he is saying in many crucial things as his accent is very strong and he talks very fast. It could have been nice if the CC option for captioning was here but it's not here. Thank you anyway Professor - I can see many got it better than I did.

[@VenkateshMane]

Thanks for the comments

[@ravim6197]

Very good and informative

[@VenkateshMane]

Thank you sir

[@mansouralblooshi3004]

Thank for sharing Ven

[@karthikkperla90]

Hello Sir, I would like to add one question Why we only insert a120 Ohms as a terminating resistor in CAN network?

[@VenkateshMane]

It is as per ISO 11898.

[@mytheenmuhammed4156]

for impedence matching of CAN nodes and avoid reflection using 120 ohm resistor's in both end of CAN network

[@nagrajullasgokarnkar6366]

Sir please make complete videos on can and autosar

[@1Saadaal]

thank you first of all tha i am using deepsea 6020 controller attached to deutz engine

[@VenkateshMane]

Sorry I have not used this controller

[@shamsadpk6955]

Very much informative. Please take care the presentation part to make it best. Thankyoi

[@VenkateshMane]

Thank you

[@prakashcs0143]

Why it is limited to maximum of 1 mbps?

[@prasadlakku1668]

really helpfull

[@sachinsonar3762]

Thanks! Very useful information...

[@ankitabhise3883]

Please make video on I2C ,SPI Protocols....

[@karthikchin2427]

It will be a great help if you show the working i.e transmission and reception of data programmatically with ARM controllers...

[@VenkateshMane]

Yes tell me how can I help you

[@karthikchin2427]

@@VenkateshMane show how to program CAN protocol transmitting and receiving using some controller preferably ARM family

[@vanessaingrid7582]

Thanks @ Venkatesh Mane. Could you do the same for other bus systems like FlexRay, MOST, LIN?

[@VenkateshMane]

Sure i will do it soon

[@VenkateshMane]

I have made a video on LIN, you can have a look

[@mohammadarifkhanies819]

CAN ANY ONE PROVIDE ME UDS INTERVIEW QUESTION AND CAPL ALSO

[@shashwatssanghavi]

Thank you for this nice video Mr. Mane. With all due respect, I'd like to add that at time 4:47, slide contents may require correction for better accuracy in visual information. 1mbps~1Mbps & "Transcievers".

[@VenkateshMane]

Thanks for the feedback

[@tharunkumar4862]

hi everyone, I have one query regarding the error frame. if can controller detects any error, then the current message is discarded and the error frame is transmitted as per tx and RX counter. in error handling can be done two types one transmitter and another receiver. If the transmitter detected bit error then the transmitter sends an error frame. if the receiver side detects any error then the transmitter only transmits an error frame or receiver side transmits error frame.

[@VenkateshMane]

Any node if detects error it will transmit error frame, does not matter receiver or transmitter

[@ajaykumaralahari6940]

How will you troubleshoot if you identify ack error or bit error ??? Can you please answer this

[@venkatesan.kkrish4733]

Dear Venkatesh In can network once the transmission done the transmitter node will wait for ACK but it is message broadcasting so how does the receiver knows this message came from particular node could you please give any example code for TX and Rx side node

[@VenkateshMane]

CAN netork follows CSMA carrier sens multiple access, any bit sent by any node will be read by all including sender, And more importantly CAN is message based not addressed based, every node in the network knows what ID whose is sending that ID during design

[@VenkateshMane]

Watch out for more detailed video on CAN Shortly

[@venkatesan.kkrish4733]

@@VenkateshMane But in transmit frame there is no sender information. in case if receiver sending ACK to all nodes while message overwriting there are two nodes will get ACK then it will become wrong for one node could you please give any example code if you give your contact number it will useful to discuss for us

[@VenkateshMane]

@@venkatesan.kkrish4733 sender info won't be there in can frame, but that is know to every node during design phase, which node send , which ID

[@naveenkumarn4622]

Thanks Venkatesh :-) useful

[@VenkateshMane]

thank you naveen

[@deepikadeepu7560]

This course is enough for embedded automotive...? I just wanna switch to automotive domain so just for confirmation

[@VenkateshMane]

Definitely helpful

[@Raj73631]

what's the significance of bus load?

[@VenkateshMane]

If bus load is higher then it affects speed(bit rate) and also lower priority messages will sufer

[@weekendeats348]

sir I read CAN uses CSMA/CA not CSMA/CD

[@GabrielNBarta]

Hello, I didn't understand the answer at 10:43. Why is the CAN BUS terminated with 120 ohms at each end?

[@VenkateshMane]

To avoid signal reflections 120 ohm resistor is used and it is as per the iso standard

[@sridurga1818]

Regarding Error confinement :- Stmt 1:- you said @ error active state(*255 - Bus off state By considering stmt 2, stmt 1 is wrong. Please clarify this doubt .

[@VenkateshMane]

When counter value is less than 127, it will send 6 dominant bits on the bus not inside register

[@sridurga1818]

@@VenkateshMane At 23min:43 secs you said that Error active includes 6 dominant bit followed by 8 resissive bits.which means the decimal value of counter is 255. Please give me clarification.

[@VenkateshMane]

every node in the network has two counter receive error counter and transmit error counter. If error is detected node will increment counter and if counter value is less than 127 then it will send 6 dominant bits followed by 8 recessive bits

[@sridurga1818]

@@VenkateshMane Ok.. Why sending 6 dominant bits followed by 8 recessive bits . Is it follow any rule..?

[@VenkateshMane]

Yes it is as per protocol rule

[@nagarajraj5949]

Explain how data trasmited in can

[@VenkateshMane]

Sure i will upload some more videos

[@nashs.4206]

Good, thorough video. I have a few questions though: 1) Is the "arbitration ID" the same as "message ID"? I see different websites and resources say that the arbitration ID is used to determine which of the nodes gets priority. 2) When the arbitration process is going on, what is physically happening in the actual CAN bus wires? I know that several nodes can all attempt to transmit data through the bus if they detect that the bus is idle. I know that to transmit a recessive bit (1), the voltage levels of both the CAN-H and CAN-L lines go at ~2.5 V (so that the differential voltage is 0 V), and that to transmit a dominant bit (0), the CAN-H line goes to ~3.5 V and CAN-L line goes down to 1.5 V. I'm assuming that it is the nodes that forces these lines to go to their respective voltage values. Now, my question is, if there are multiple nodes attempting to use the bus, wouldn't there be a superposition/overlap of voltage values since each node will be forcing the CAN-H and CAN-L lines to go to different voltage values?

[@VenkateshMane]

1. Yes, both are same

[@VenkateshMane]

2. CAN makes use of wired AND logic

[@nashs.4206]

@@VenkateshMane Sorry I should have been more clear in my question. Okay, suppose that we have node A, and node B. Suppose that the arbitration ID of node A is 0111, and the arbitration ID of node B is 1011. Now, to proceed with the arbitration, node A sends out 0 whereas node B sends out 1. What this physically means is that when 0 is sent out to the bus, the CANH line is set to 3.5 V, whereas the CANL line is set to 1.5 V. Similarly, when a 1 is sent out to the bus, both the CANH and CANL lines are set to 2.5 V. This is where my confusion arises. Node A sends out 0, and *at the same time*, node B sends out a 1. How can the CANH and CANL lines be at 3.5 V and 1.5 V (to denote 0), and 2.5 V (to denote 1) at the same time?

[@VenkateshMane]

@@nashs.4206 It is taken care by the transceiver connected to the node.

[@A1Telugu_EyeChappieTV]

What ACK error does ?

[@VenkateshMane]

If ACK error occurs then error frame will be sent by the sender

[@ajsfalcon9045]

Hi sir pleas hindi videos uplode karen , pleas

[@VenkateshMane]

billkull karunga toda time lagta hai

[@1Saadaal]

please help me to configure can to transmit alarms from engine and remote device pls your contact

[@VenkateshMane]

Which controller are you using,?

[@1Saadaal]

sorry controller is 6120

[@stanley8503]

Your explanation about arbitration was not 100% correct. Simply we can say that, the node which has 0 on lower bits of identifier wins higher priority. That's why air bag ECU wins the higher priority. Otherwise good. Keep going

[@VenkateshMane]

No, its not lower bits of identifiers, its MSB bits which makes the difference, msb bits are sent first not lsb

[@stanley8503]

"Lower Binary Value has higher priority". Suppose node A has 00000000 value and node B has 00000011 value in identifier bits. In this scenario node A wins higher priority because it has Os in lower order fields of identifier. Check above answer with some other useful docs. Its not like SPI. MSB first LSB next.

[@VenkateshMane]

What about the Id 500 and 403? Which identifier has lower binary value, 500 right, then which message is sent 500 or 403? 403 will get the bus.

[@stanley8503]

Yes. That's y I said "Lower Binary value has higher priority". My explanation was wrong. But MSB bit of identifier not decides the priority.

[@VenkateshMane]

I said msb bits makes the difference, arbitration starts with msb bit, ofcourse as I said in my video lower identifiers will get the bus access, Lower the identifiers higher the priority

[@vetribarnabas4711]

Can you send this file

[@dineshtanati5849]

Please speak normally don’t use accent,

[@VenkateshMane]

Ok, thanks for your feedback

[@shahrukhkhanmalik9095]

Yes. Requires practice. Take it as a feedback only. Don't take it as wrong.