Hi Rui, I have reverted the changes to uEmv to comment out the #dtb line
I then modified am335x-boneblack.dts to uncomment so that it looks like the following: /*can0: P9.19, P9.20: disable: i2c2: cape eeprom */ /* can0: peripheral */ #include "am335x-can0.dtsi" /* can0: pinmux */ #include "am335x-bone-can0.dtsi" /* can1: P9_24, P9_26 */ #include "am335x-can1.dtsi" #include "am335x-bone-can1.dtsi" I built the dtb using dtb-rebuilder and copied the new am335x-boneblack.dtb to /boot/dtbs/3.14.35-ti-rt-r56/ and rebooted the system. Now when i look in the /sys/kernel/debug/pinctrl/44e10800.pinmux/pinmux-pins pin 94 (44e10978.0): P9_20_pinmux.47 (GPIO UNCLAIMED) function pinmux_P9_20_i2c_pin group pinmux_P9_20_i2c_pin pin 95 (44e1097c.0): P9_19_pinmux.46 (GPIO UNCLAIMED) function pinmux_P9_19_i2c_pin group pinmux_P9_19_i2c_pin pin 96 (44e10980.0): P9_26_pinmux.53 (GPIO UNCLAIMED) function pinmux_P9_26_can_pin group pinmux_P$ pin 97 (44e10984.0): P9_24_pinmux.51 (GPIO UNCLAIMED) function pinmux_P9_24_can_pin group pinmux_P$ It seems that the DCAN0 is still associated with i2c and not can0. However I can now use ip link set can1 type can bitrate 125000 triple-sampling on loopback on ip link set can0 type can bitrate 125000 triple-sampling on loopback on and bring up both can devices. If i do candump can0 and cangen can0 i do see loopback messages however when connected with two transceivers one connected to can0 and other can1 and then running cangen can0 and candump can1 i dont get any transmitted bits. I tried using a scope on CANTX P9_26 to ground and find that nothing is coming out of this pin. I also found that running cangen can0 after a few seconds i am getting this error. cangen can0 write: No buffer space available could you give me a step by step from boot up to get the canbus running to see if there is something I am missing? Thanks Mark On Thursday, 9 April 2015 05:30:55 UTC+10, RFA wrote: > > Hi Mark, > > I would rebuild the device tree to make sure can0 is included. > > > - Revert the changes to uEnv. > - download Robert Nelson's dtb-rebuilder ( > https://github.com/RobertCNelson/dtb-rebuilder) and checkout 3.14-ti. > - edit am335x-boneblack.dts to include can0. > - make am335x-boneblack.dtb and replace the original file in > /boot/dtbs/3.14.35-ti-r56/ > - reboot. > > > Regards > Rui > > On Wednesday, April 8, 2015 at 2:20:29 PM UTC+1, Mark Irwin wrote: >> >> Hi, >> >> I have been trying to build a proof of concept system using two >> beaglebone black units with there DCAN1 (pins P9_24 and P9_26) and two can >> transcievers TI SN65HVD251P. >> The can transceivers are powered from the same 5V bench supply as both of >> the beaglebone blacks. the canh and canl pins are terminated at both ends >> by 120R resistors to ensure the 60R bus impedence. >> >> I was following the instructions in other posts about updating to the >> latest debian version and then upgrading the kernel to 3.14. This i have >> done. >> uname -a >> Linux beaglebone 3.14.35-ti-rt-r56 #1 SMP PREEMPT Sun Mar 29 01:13:05 UTC >> 2015 armv7l GNU/Linux >> >> I added dtb=am335x-boneblack-can1.dtb to the uEnv.txt >> >> I have also installed the canbus tools within the image so i can attempt >> a cangen can0 and candump can0. >> >> On system boot i am doing the following: >> >> modprobe can >> modprobe can-dev >> modprobe can-raw >> >> ip link set can0 type can bitrate 125000 triple-sampling on >> ifconfig can0 up >> >> however if i use candump can0 and cangen can0 within two seperate putty >> sessions i dont see anything. >> >> If I create a vcan bus i do see the messages in loopback. >> sudo modprobe vcan >> sudo ip link add dev vcan0 type vcan >> sudo ifconfig vcan0 up >> >> Previously I was using an older debian image and found that when i ran >> cangen can0 that the buffer would give me an error that it was full. >> however now with the latest image i am not getting the bufer full message >> but still not seeing anything on the candump. What should i expect to see >> here? >> >> Can anyone see where I have gone wrong or a step i am missing? >> >> Thanks in advance. >> >> Mark >> >> -- 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.
