transmittest not working (receivetest works)

[youngbo]

I've build version 8.5.1 of the linux driver, by means of:
make
sudo make install
sudo modprobe pcan

I have 120 Ohms termination in my CAN cables.

Unfortunately, I can receive messages but can't transmit. I faced CAN status is BUSOFF.
What should I check?

[S.Grosjean]

Hi,

Please give us the results of:

$ cat /proc/pcan

$ uname -a

and tell us a bit more on how do you use the transmittest program, please.

Regards,

Stéphane

[youngbo]

$ uname -a


https://ibb.co/d2o26b

This picture is the result of using pcanread in pcanbasic and $ cat /proc/pcan.


https://ibb.co/cH7Umb

This picture is the result of using pcanwrite in pcanbasic and $ cat /proc/pcan.


https://ibb.co/c8ZaRb

[S.Grosjean]

Hi,

Thanks. So it looks like you're having access to the CAN bus with a PCAN-USB at 500 kbps, right?

Regarding the "status" column, we don't see any BUSOFF status but 0x3 says that the Tx queue of the driver and the controller are full.

Next, you've asked about an issue with transmittest, so we first need to know how you use it: which parameters do you put on the command line, please ?

Finally, try this command please:

Code: Select all

$ pcanfdtst tx -b 500k -n 100 -i 0x2b1 -I 8 /dev/pcanusb32

This command writes 100x CAN frames with ID=0x2b1 (like yours) and 8 data bytes over the CAN bus through the PCAN-USB setup to connect with bitrate=500 kbps.

Regards,

Stéphane

[youngbo]

Thank you for your comment.

I did what you asked me to try($ pcanfdtst tx -b 500k -n 100 -i 0x2b1 -I 8 /dev/pcanusb32). As a result, a message is sent but it seems not to be received by the receiver.


Also, I tried sending and receiving messages through PCAN-VIEW on Windows and it works correctly.

I tested using the example 'pcanwrite' in PCAN-Basic, as follows:


https://ibb.co/j5L3xG

[S.Grosjean]

Hello,

Ok, AFAIU the status column 0x53 shows the BUSOFF state. So there's something wrong on your CAN bus.

Please verify each node connected to the bus and their bitrate. Notice that if there's only one other node on the bus, it MUST not be setup in Listen Only mode. Verify each piece of cable of your bus. Be sure to have two resistors (only) on each end.

To help to fix on the software side, your recent kernel includes some other driver that is compatible with the PCAN-USB. Please do the following commands:

Code: Select all

$ sudo rmmod pcan
$ sudo apt-get install can-utils
$ sudo modprobe peak_usb
$ dmesg | grep peak

You should see something like:

Code: Select all

[ 1123.160528] peak_usb 3-9.2:1.0 can0: attached to PCAN-USB channel 0 (device XX)

Then, type:

Code: Select all

$ sudo ip link set can0 up type can bitrate 500000
$ cansend can0 2b1#0011223344556677

This last line writes the frame ID=0x2b1 with data=[00 11 22 33 44 55 66 77]. You can repeat that line as many times as you like. Tell us if it works better. Then, type:

Code: Select all

$ ip -s -d link show can0

and give us the result please.

Regards,

Stéphane