can_xavier

CAN Bus Drive Script

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Those scripts are quiet easy and just for reference.

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Configure CAN controller

• Install busybox, we need a tool called devmem:

sudo apt install busybox

• Check current values of related registers:

sudo busybox devmem 0x0c303000

sudo busybox devmem 0x0c303008

sudo busybox devmem 0x0c303010

sudo busybox devmem 0x0c303018

• We can continue to modify registers if returned values are exactly these:

0x0000C055

0x0000C055

0x0000C059

0x0000C059

• Use devmem to modify registers:

sudo busybox devmem 0x0c303000 32 0x0000C400

sudo busybox devmem 0x0c303008 32 0x0000C458

sudo busybox devmem 0x0c303010 32 0x0000C400

sudo busybox devmem 0x0c303018 32 0x0000C458

• Check modified values of related registers:

sudo busybox devmem 0x0c303000

sudo busybox devmem 0x0c303008

sudo busybox devmem 0x0c303010

sudo busybox devmem 0x0c303018

• It supposed to be successful if returned values are exactly these:

0x0000C400

0x0000C458

0x0000C400

0x0000C458

• Load prebuilt but not loaded drivers(Please modify path if system has been updated)

sudo insmod /lib/modules/4.9.108-tegra/kernel/net/can/can.ko

sudo insmod /lib/modules/4.9.108-tegra/kernel/net/can/can-raw.ko

sudo insmod /lib/modules/4.9.108-tegra/kernel/net/can/can-bcm.ko

sudo insmod /lib/modules/4.9.108-tegra/kernel/net/can/can-gw.ko

sudo insmod /lib/modules/4.9.108-tegra/kernel/drivers/net/can/can-dev.ko

sudo insmod /lib/modules/4.9.108-tegra/kernel/drivers/net/can/mttcan/native/mttcan.ko

• Or you can use modprobe to mount CAN Controller

sudo modprobe can

sudo modprobe can_raw

sudo modprobe mttcan

Notice: It seems that use modprobe is same as load drivers, so either is OK.

• Configure CAN controller with 1Mbps baudrate

sudo ip link set can0 type can bitrate 1000000

sudo ip link set can1 type can bitrate 1000000

• Configure CAN controller as loopback test mode

sudo ip link set can0 type can bitrate 1000000 loopback on

sudo ip link set can1 type can bitrate 1000000 loopback on

• Open CAN controller

sudo ip link set up can0

sudo ip link set up can1

• Check the status of CAN controller

ip -s -d link show can0

ip -s -d link show can1

• Close CAN controller

sudo ip link set down can0

sudo ip link set down can1

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Test CAN0 controller(loopback test)

• Open two treminals A and B,run this command in treminal A:

candump can0

• Now the command executed in terminal A should under a listener mode and user inputs are not accepted.Now execute the following command in terminal B and watch what will happen in terminal A.

cansend can0 5A1#1122334455667788

• It supposed to be successful if returned values are these:

can0 5A1 [8] 11 22 33 44 55 66 77 88

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Test two CAN controllers if you have configured hardware transceiver circuit.

• Open two treminals A and B,run this command in treminal A:

candump can0

• Now the command executed in terminal A should under a listener mode and user inputs are not accepted.Now execute the following command in terminal B and watch what will happen in terminal A.

cansend can1 5A1#1122334455667788

• It supposed to be successful if returned values are these:

can0 5A1 [8] 11 22 33 44 55 66 77 88