diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/RPi_microcontroller.md | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/docs/RPi_microcontroller.md b/docs/RPi_microcontroller.md new file mode 100644 index 00000000..63f2d3c8 --- /dev/null +++ b/docs/RPi_microcontroller.md @@ -0,0 +1,148 @@ +This document describes the process of running Klipper on a RPi +and use the same RPi as secondary mcu. + +Why use RPi as a secondary MCU? +=============================== +Often the MCUs dedicated to controlling 3D printers have a limited and +pre-configured number of exposed pins to manage the main printing +functions (thermal resistors, extruders, steppers ...). +Using the RPi where Klipper is installed as a secondary MCU gives the +possibility to directly use the GPIOs and the buses (i2c, spi) of the RPi +inside klipper without using Octoprint plugins (if used) or external +programs giving the ability to control everything within the print GCODE. + +**Warning**: If your platform is a _Beaglebone_ and you have correctly followed the installation steps, the linux mcu is already installed and configured for your system. + +Install the rc script +===================== + +If you want to use the host as a secondary MCU the klipper_mcu process must run before the klippy process. + +After installing Klipper, install the script. run: +``` +cd ~/klipper/ +sudo cp "./scripts/klipper-mcu-start.sh" /etc/init.d/klipper_mcu +sudo update-rc.d klipper_mcu defaults +``` + +Building the micro-controller code +================================== + +To compile the Klipper micro-controller code, start by configuring it +for the "Linux process": +``` +cd ~/klipper/ +make menuconfig +``` + +To build and install the new micro-controller code, run: +``` +sudo service klipper stop +make flash +sudo service klipper start +``` + +Remaining configuration +======================= + +Complete the installation by configuring Klipper secondary MCU +following the instructions in +[RasperryPi example config](../config/example-rasperry-pi.cfg) and +[Multi MCU example config](../config/example-multi-mcu.cfg). + +Optional: Identify the correct gpiochip +======================================= +On Rasperry and on many clones the pins exposed on the GPIO belong to the first gpiochip. They can therefore be used on klipper simply by referring them with the name `gpio0..n`. +However, there are cases in which the exposed pins belong to gpiochips other than the first. For example in the case of some OrangePi models or if a Port Expander is used. In these cases it is useful to use the commands to access the _Linux GPIO character device_ to verify the configuration. + +To install the _Linux GPIO character device - binary_ on a debian based distro like octopi run: +``` +sudo apt-get install gpiod +``` + +To check available gpiochip run: +``` +gpiodetect +``` + +To check the pin number and the pin availability tun: +``` +gpioinfo +``` + +The chosen pin can thus be used within the configuration as `gpiochip<n>/gpio<o>` where **n** is the chip number as seen by the `gpiodetect` command and **o** is the line number seen by the` gpioinfo` command. + +***Warning:*** only gpio marked as `unused` can be used. It is not possible for a _line_ to be used by multiple processes simultaneously. + +For example on a RPi 3B+ where klipper use the GPIO20 for a switch: +``` +$ gpiodetect +gpiochip0 [pinctrl-bcm2835] (54 lines) +gpiochip1 [raspberrypi-exp-gpio] (8 lines) + +$ gpioinfo +gpiochip0 - 54 lines: + line 0: unnamed unused input active-high + line 1: unnamed unused input active-high + line 2: unnamed unused input active-high + line 3: unnamed unused input active-high + line 4: unnamed unused input active-high + line 5: unnamed unused input active-high + line 6: unnamed unused input active-high + line 7: unnamed unused input active-high + line 8: unnamed unused input active-high + line 9: unnamed unused input active-high + line 10: unnamed unused input active-high + line 11: unnamed unused input active-high + line 12: unnamed unused input active-high + line 13: unnamed unused input active-high + line 14: unnamed unused input active-high + line 15: unnamed unused input active-high + line 16: unnamed unused input active-high + line 17: unnamed unused input active-high + line 18: unnamed unused input active-high + line 19: unnamed unused input active-high + line 20: unnamed "klipper" output active-high [used] + line 21: unnamed unused input active-high + line 22: unnamed unused input active-high + line 23: unnamed unused input active-high + line 24: unnamed unused input active-high + line 25: unnamed unused input active-high + line 26: unnamed unused input active-high + line 27: unnamed unused input active-high + line 28: unnamed unused input active-high + line 29: unnamed "led0" output active-high [used] + line 30: unnamed unused input active-high + line 31: unnamed unused input active-high + line 32: unnamed unused input active-high + line 33: unnamed unused input active-high + line 34: unnamed unused input active-high + line 35: unnamed unused input active-high + line 36: unnamed unused input active-high + line 37: unnamed unused input active-high + line 38: unnamed unused input active-high + line 39: unnamed unused input active-high + line 40: unnamed unused input active-high + line 41: unnamed unused input active-high + line 42: unnamed unused input active-high + line 43: unnamed unused input active-high + line 44: unnamed unused input active-high + line 45: unnamed unused input active-high + line 46: unnamed unused input active-high + line 47: unnamed unused input active-high + line 48: unnamed unused input active-high + line 49: unnamed unused input active-high + line 50: unnamed unused input active-high + line 51: unnamed unused input active-high + line 52: unnamed unused input active-high + line 53: unnamed unused input active-high +gpiochip1 - 8 lines: + line 0: unnamed unused input active-high + line 1: unnamed unused input active-high + line 2: unnamed "led1" output active-low [used] + line 3: unnamed unused input active-high + line 4: unnamed unused input active-high + line 5: unnamed unused input active-high + line 6: unnamed unused input active-high + line 7: unnamed unused input active-high +``` |