# BPI-M1 CAN Bus

In order to port [can4linux](https://sourceforge.net/projects/can4linux/) to the BananaPi, the CAN module description is needed from the A20 hardware manual. can4linux is a character-driver-based Linux driver used already on desktop PCs and embedded platforms like Freescale FlexCAN (the i.MX series of micro controllers) or Xiliny Zynq.

There is a more detailed document about CAN on the A20 at [https://dl.linux-sunxi.org/A20/CAN Bus1.pdf](https://dl.linux-sunxi.org/A20/CAN%20Bus1.pdf)

**This is a tutorial for using CAN BUS on bananapi with bananian 15-01**

Thank selqcir share this example:

* Download and install "bananian-1501.img" into 8 GB SDCard.
* Expand the root file system using "bananian-config"
*   Install missing package:

    ```
    apt-get install git
    apt-get update
    apt-get upgrade
    reboot
    ```
*   Get last bananian available, and continu to install missing package:

    ```
    git clone https://github.com/Bananian/linux-bananapi
    apt-get install build-essential u-boot-tools uboot-mkimage 
    apt-get install libusb-1.0-0 libusb-1.0-0-dev git wget fakeroot kernel-package zlib1g-dev libncurses5-dev
    apt-get install subversion
    ```
*   Build kernel:

    ```
    cd linux-bananapi
    make menuconfig
    ```
*   Exit without saving when menu appears

    ```
    zcat /proc/config.gz > /root/linux-bananapi/.config
    make uImage modules
    make INSTALL_MOD_PATH=output modules_install
    ```
* At this step, kernel should be compiled and "Module.symvers" should be available
*   Then rename modules and firmware provide by Bananian, and replace by the new one.

    ```
    mv /lib/modules /lib/modules.old
    mv /lib/firmware /lib/firmware.old
    mv /root/linux-bananapi/output/lib/modules /lib/modules
    mv /root/linux-bananapi/output/lib/firmware /lib/firmware
    ```
*   Same for uImage:

    ```
    mount /dev/mmcblk0p1 /mnt
    cd /mnt
    mv uImage uImage.old
    mv /root/linux-bananapi/arch/arm/boot/uImage /mnt
    reboot
    ```
*   Create link for further build:

    ```
    cd /lib/modules/3.4.104/
    ln -s /root/linux-bananapi build
    cd ~
    ```
*   Get Can4Linux and build it:

    ```
    svn checkout https://svn.code.sf.net/p/can4linux/code/trunk can4linux-code
    cd /root/can4linux-code/can4linux/
    make TARGET=BANANAPI
    ```
*   Install module for each startup of the board:

    ```
    insmod can4linux.ko
    cp can4linux.ko /lib/modules/3.4.104/kernel/net/can/
    depmod -A -v
    modprobe -v can4linux
    echo "" >> /etc/modules ; echo "can4linux" >> /etc/modules
    reboot
    ```
*   Build CAN example

    ```
    apt-get install swig
    apt-get install python-dev
    cd can4linux-code/can4linux-examples/
    ```
*   Update CAN speed and device in file "pyCan-example.py"

    ex:

    ```
    # setting the device number
    device = 0
    defaultBaudrate = '250'
    ```
* Connect CAN transceiver and CAN bus, and check with for example:

```
   python pyCan-example.py
```

That's all

With this method, kernel version is "Linux bananapi 3.4.104" instead of "Linux bananapi 3.4.104+", because i was unable to find same sources than Bananian 15-01 , but CAN bus work !

Feel free to comment or update.
