Hi John, I'm attempting to enable CAN support for a USB/CAN from a Lawicel. We have a custom board and need to use pin D17/D18 and E17/E18 for CAN1 and CAN2.
The pad names in u-boot/arch/arm/include/asm/arch-am33xx/mux_am33xx.h for the BBB includes i2c0_sda (pin C17) and i2c0_scl (pin C16), but I don't see names for i2c2_scl (pin D17) and i2c2_sda (pin D18), nor tstpt1 (pin E17) nor TP9 (pin E18), 1. Did I miss the names for these pins in u-boot? 2. If u-boot does not support these pins, should they be added to u-boot, and/or added to the kernel to support these pins? Should these pins be pinmuxed in both uboot and the kernel, or only in the kernel dts? Checking now to see if the kernel has support for these pins. thx, Tracy On Wednesday, April 8, 2015 at 8:20:29 AM UTC-5, 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/e6297438-0999-4320-916e-f41d74671533%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
