Bus-off on any sending attempt - PCAN - USB

[MarcinSzn]

For a few days I am facing problem with PCAN - USB.

I am using Can network with bitrate of 500 kBit/s and extended IDs.

On any transmit attempt (tried with different Can networks) Peak goes into Bus-OFF state. Moreover Peak is no acknowledging any other Can messages although option "Listen-Only Mode" being turned off. Here is status of the bus when transmission attempt occurs:

Zrzut ekranu 2021-09-01 132605.png (26.42 KiB) Viewed 6856 times

And registered by another CAN device:

Zrzut ekranu 2021-09-01 132844.png (8.56 KiB) Viewed 6856 times

Before sending attempt PeakUSB is receiving CAN messages correctly.
The attempted message is not sent to CAN network.

I would be very grateful for any help

[M.Heidemann]

Hi,

Check the following:

Is your bus properly terminated (120 Ohms on both bus ends)?

Does your bitrate match? (Also check the sampel-Point)

Check for duplicate messages, if the two identical IDs collide they
also could cause this behavior.

Check your cabling, is it correct? Ar there any defects?

Please share your findings with us

Best Regards

Marvin

[MarcinSzn]

Is your bus properly terminated (120 Ohms on both bus ends)?

Yes, I've also tried with no, or single termination with no difference.

Does your bitrate match? (Also check the sampel-Point)

Yes, 3 devices have 500 kBit/s with sampling point of 87,5%. 2 devices can communicate with each other with no problem. Peak can read whole communication, but is causing error with sending attempt.

Also Peak is having exactly the same errors when is the only device on bus network.

Check for duplicate messages, if the two identical IDs collide they also could cause this behavior.

Every device is sending messages with different IDs

Check your cabling, is it correct? Ar there any defects?

Unfortunately I couldn't find any problem with cabling. It is a test network with overall length less than 1m

[M.Heidemann]

Heello,

Thank you for your fast reply.

We suspect this still comes down to the bitrate settings.

We assume you use PCAN-View?

Please try a Btr0Btr1 of "0x4114h" as a test:

01.png (3.42 KiB) Viewed 6850 times

02.png (3.53 KiB) Viewed 6850 times

03.png (22.47 KiB) Viewed 6850 times

04.png (8.11 KiB) Viewed 6850 times

Additionally you could check if your device has an defective transceiver:

viewtopic.php?f=120&t=52

Best Regards

Marvin

[MarcinSzn]

Thank you for answer.

It looks like trans-receiver is defective because:

4. Please measure with a multimeter (DC measurement area) the voltage the between pin 2 (CAN-L) and pin 3 (GND) from the 9 pole D-SUB. You should measure 2.5V +/- 0.2V

Voltage is: 4.21

5. Now measure the voltage between pin 7 (CAN-H) and pin 3 (GND) from the 9 pole D-SUB, you should also measure 2.5V +/- 0.2V

Voltage is: 1.54

Thank you for support!

[M.Heidemann]

Dear Marcin,

Did you measure these values while idle?

Please let us know

Best Regards

Marvin

[MarcinSzn]

Hello,

Sorry for the slow response. Yes I've measured above values on idle (nothing connected to PeakCAN, RED LED light on, not blinking)

When device is connected (RED LED blinking) values are essentially the same

[M.Heidemann]

Hello,

Thanks for the info,
just wanted to make sure this also
was mesaured in idle.

Sounds like either a Transceiver defect or a defective opto-decoupler (If you device is a IPEH-002022)

Best Regards

Marvin