Description

This repository contains the configuration for kernel drivers that are required for the CAN-Zero board.

PWM

Configuration for kernel 6.6

1. Add the following line to the /boot/firmware/config.txt file:

   sudo nano /boot/firmware/config.txt
   

   dtoverlay=pwm-2chan,pin=12,func=4,pin2=13,func2=4
   

2. Restart the device:

   $ sudo reboot
   

Configuration for kernel 4.9

1. Add the following line to the /boot/config.txt file:

   dtoverlay=pwm-2chan,pin=12,func=4,pin2=13,func2=4
   

2. Restart the device:

   $ sudo reboot
   

Configuration for kernel 4.4

1. Install the device tree compiler:

   sudo apt install device-tree-compiler
   

2. Download pwm-2chan-with-clk-overlay.dts from this repository.
3. Compile the device tree:

   sudo dtc -@ -I dts -O dtb -o pwm-2chan-with-clk-overlay.dtbo pwm-2chan-with-clk-overlay.dts
   

4. Copy the new file to /boot/overlays/:

   sudo cp pwm-2chan-with-clk-overlay.dtbo /boot/overlays/
   

5. Add the following line to the /boot/config.txt file:

   dtoverlay=pwm-2chan-with-clk-overlay,pin=12,func=4,pin2=13,func2=4
   

6. Restart the device:

   sudo reboot
   

Adding user to the right permission group - kernel 6.6

sudo nano /etc/udev/rules.d/99-com.rules

Add the following lines:

SUBSYSTEM=="pwm", ACTION!="remove", PROGRAM="/bin/sh -c 'echo 0 > /sys/class/pwm/pwmchip0/export'"
SUBSYSTEM=="pwm", ACTION!="remove", PROGRAM="/bin/sh -c 'echo 1 > /sys/class/pwm/pwmchip0/export'"

Test the configuration for old kernel

1. Give every user access to the PWM controls:

   sudo chmod -R 0666 /sys/class/pwm/pwmchip0/export
   sudo chmod -R 0666 /sys/class/pwm/pwmchip0/unexport
   

2. Create pwm0 and pwm1:

   echo 0 > /sys/class/pwm/pwmchip0/export
   echo 1 > /sys/class/pwm/pwmchip0/export
   

3. Give every user access to the PWM:

   chmod -R 0666 /sys/class/pwm/pwmchip0/*
   

   Or alternatively to 1-3 add to /etc/rc.local the following lines:

   sudo chmod -R 0666 /sys/class/pwm/pwmchip0/export
   echo 0 > /sys/class/pwm/pwmchip0/export
   echo 1 > /sys/class/pwm/pwmchip0/export
   

4. Use pwm0.
   4.1. Set period (in ns):

   echo 20000000 > /sys/class/pwm/pwmchip0/pwm0/period
   

   4.2. Set duty cycle (in ns):

   echo 5000000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle
   

   4.3. Enable pwm0:

   echo 1 > /sys/class/pwm/pwmchip0/pwm0/enable
   

5. Remove pwm0:

   echo 0 > /sys/class/pwm/pwmchip0/unexport
   

Test the configuration

 pwm_test.py --chip 0 --channel 0 --period 20 --duty 1.5

CAN Bus

Configuration (kernel 5.15)

dtparam=spi=on 
dtoverlay=spi1-1cs,cs0_spidev=off
dtoverlay=mcp2515,spi1-0,oscillator=16000000,interrupt=25   

Configuration (both kernel 4.4 and 4.9)

1. Install the device tree compiler:

   sudo apt install device-tree-compiler
   

2. Download mcp2515-can2-overlay.dts from this repository.
3. Compile the device tree:

   sudo dtc -@ -I dts -O dtb -o mcp2515-can2-overlay.dtbo mcp2515-can2-overlay.dts
   

4. Copy the new file to /boot/overlays/:

   sudo cp mcp2515-can2-overlay.dtbo /boot/overlays/
   

5. Add the following lines to the /boot/config.txt file:

   dtparam=spi=on
   dtoverlay=spi1-1cs,cs0_spidev=off
   dtoverlay=mcp2515-can2-overlay,oscillator=16000000,interrupt=25
   

6. Add the following lines to the /etc/network/interfaces file:

   auto can0
   allow-hotplug can0
   iface can0 inet manual
       pre-up /bin/ip link set can0 up type can restart-ms 100 bitrate 500000
       down /bin/ip link set can0 down
   

7. Install can-utils:

   sudo apt install can-utils
   

8. Restart the device:

   $ sudo reboot
   

9. Check if the can0 interface is up:

   ifconfig | grep can0
   

I2C and Serial

Configuration (both kernel 4.4 and 4.9)

last kernel 6.1 use sudo raspi-config

1. Add the following lines to the /boot/config.txt file:

   enable_uart=1
   dtparam=i2c_arm=on
   dtparam=i2c1=on
   dtparam=i2c1_baudrate=1000000
   dtoverlay=pi3-disable-bt
   

2. Install i2c-tools:

   sudo apt install i2c-tools
   

3. Restart the device:

   $ sudo reboot
   

4. Check I2C:

   i2cdetect -y 1
   

build Ardupilot

git clone --recurse-submodules https://github.com/karu2003/ardupilot	
cd ardupilot	
git checkout docker_rpi	
docker build . -t ardupilot

for Raspberry Pi 1, Zero

docker build . -f Dockerfile_rpi1_zero -t ardupilot_rpi

for Raspberry Pi 2, 3

docker build . -f Dockerfile_rpi2_3 -t ardupilot_rpi

for Raspberry Pi 3A+, 3B+, 4

docker build . -f Dockerfile_rpi3b_4 -t ardupilot_rpi

git checkout master

docker run --rm -it -v `pwd`:/ardupilot ardupilot_rpi:latest bash -c "./waf clean && ./waf configure --board=canzero --static && ./waf build"