I suppose it is also possible you have your receive / transmit lines hooked up backwards. When first setting up here, that happened to us too.
When attempting to find the right baud rate for our system, a first incorrect value actually caused our BBB to lock up, and reset the external CAN device. On Tue, Jun 9, 2015 at 4:46 PM, William Hermans <[email protected]> wrote: > You need to make sure the baud rate for the CAN interface is set > correctly. e.g. you need to know the baud rate the PLC is transmitting at. > > Also the screenshot you've given is normal behavior for candump. If you > run candump, and it is unable to detect transmissions for whatever reason. > It will just sit there as in your sceenshot, until you press control + C. > > My initial guess would be that you have the baud rate set incorrectly. It > *must* match that of the CAN interface you're connecting to. > > Example: > debian@beaglebone:~$ sudo ip link set can0 up type can bitrate *250000* > > For us our baudrate is 250kbps so you can . . . > > debian@beaglebone:~$ sudo ifconfig can0 down >> >> debian@beaglebone:~$ sudo ip link set can0 up type can bitrate <your >> baud rate here > >> >> debian@beaglebone:~$ sudo ifconfig can0 up >> > > > And then try again with candump. Also, I've read that if you do not use > --listen-only with the ip command. Some devices will freak out, and stop > transmitting. But we've not yet experienced that here. > > On Tue, Jun 9, 2015 at 3:09 PM, Robert Nelson <[email protected]> > wrote: > >> On Tue, Jun 9, 2015 at 5:00 PM, Strong Industries <[email protected]> >> wrote: >> > The "other device" is a CR0403 PLC which is running an independent OS >> by IFM >> > (not networked to a linux system, so I can't ssh into it). The PLC >> device >> > is transmitting over CANbus using a known working program which we >> already >> > use in another system. >> > >> > When I do the "./candump can0", it hangs there w/ no output on the >> screen >> > when I expect data coming from the PLC device (see attached pic)... >> > >> > I am lost here, because the only other thing I can think of is setting >> some >> > type of DT overlay which I've read about on... >> > >> > >> https://learn.adafruit.com/introduction-to-the-beaglebone-black-device-tree/exporting-and-unexporting-an-overlay >> > >> > >> http://www.embedded-things.com/bbb/enable-canbus-on-the-beaglebone-black/ >> > >> > but those sites refer to Angstrom & using the cape manager (which I >> can't >> > find the directories/files for in Debian). >> >> Well, you already have can0 enabled on BBB-EXP-R cape by default... So >> the above doesn't matter.. >> >> Regards, >> >> -- >> Robert Nelson >> https://rcn-ee.com/ >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
