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Operating System installation

Revision as of 21:28, 11 April 2022 by B.Naegele (talk | contribs) (→‎Installation of the base-system)

> Main Page > Piano Expander based on Pianoteq and Odroid-N2

Ubuntu 20.04

Kernel-Version

root@odroid:~# cat /proc/version 
Linux version 4.9.277-122 (root@builder_n2) (gcc version 7.5.0 (Ubuntu/Linaro 7.5.0-6ubuntu2) ) #1 
SMP PREEMPT Mon Feb 28 14:30:14 UTC 2022

Installation of the base-system

  • The installation of the operating system is pretty easy when you are using the Linux distributions which are supported by "Hardkernel".
  • The new Operating-System which I have used is the ubuntu-20.04-4.9-mate-odroid-n2-20220228.img.xz . Download the Image from the Release Note of Ubuntu MATE 20.04.4 LTS (v3.3)-Web-Page or directly from here
  • The new Operating-System which I have used is the ubuntu-20.04-4.9-minimal-odroid-n2-20220228.img.xz . Download the Image from the Release Note of Ubuntu MATE 20.04.4 LTS (v3.3)-Web-Page or directly from here
  • A guideline for installing the Image (Hardkernel) can be found here


Optional: Install and configure WiFi-Network

Optional: Install VIM as a good commandline editor

  • In case that you have a valid network connection you can easily install the full-featured editor "VIM" by typing the following command on the console
sudo apt install vim

-> enter the password for the root-user (default: odroid) and accept that a small amount of memory is used for the installation

Enable Auto-Login

[SeatDefaults]
greeter-session=lightdm-gtk-greeter
autologin-user=odroid

Change Mate-Keymap

  • Connect a Keyboard to one of the USB-Ports and a Mouse to another one.
  • Goto "Menu -> Preferences -> Keyboard"
  • On the Tab "Layouts" you can choose the right one

Deactivate Screensaver

  • Drop down the Mate-Menu
  • Go to "Preferences -> Screensaver"
  • Deactivate the Check-Box "Activate screensaver when computer is idle"
  • In the same window press the Button "Power-Management" select "Never" for the question "Put display to sleep when inactive for:"

Optional: Gnome-Screenshot

  • If you want to make screenshots e.g. for documentation purposes you can add the tool "Gnome-Screenshot" with the following commands:
apt install gnome-screenshot

Rotating the Touch-Display

Articles regarding Display and Touch Rotation

Screen rotation

cd /usr/share/X11
mkdir xorg.conf.d
cd xorg.conf.d
vi 99-odroidn2.conf

insert the following content into this file:

# This is a minimal sample config file, which can be copied to
# /etc/X11/xorg.conf in order to make the Xorg server pick up
# and load xf86-video-fbturbo driver installed in the system.
#
# When troubleshooting, check /var/log/Xorg.0.log for the debugging
# output and error messages.
#
# Run "man fbturbo" to get additional information about the extra
# configuration options for tuning the driver.

Section "Device"
        Identifier      "FBTURBO"
        Driver          "fbturbo"
        Option          "fbdev" "/dev/fb0"
        Option          "Rotate" "CCW"
        Option          "SwapbuffersWait" "true"
        Option          "alpha_swap" "true"
EndSection
  • Ausgabe von /var/log/Xorg.0.log
root@odroid:~# cat /var/log/Xorg.0.log
[    14.551] 
X.Org X Server 1.20.13
X Protocol Version 11, Revision 0
[    14.551] Build Operating System: linux Ubuntu
[    14.551] Current Operating System: Linux odroid 4.9.277-122 #1 SMP PREEMPT Mon Feb 28 14:30:14 UTC 2022 aarch64
[    14.551] Kernel command line: root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait rw console=ttyS0,115200n8  no_console_suspend fsck.repair=yes net.ifnames=0 elevator=noop hdmimode=custombuilt cvbsmode=576cvbs max_freq_a53=1896 max_freq_a73=1800 maxcpus=6 voutmode=dvi modeline=1280,800,75000,49472,60,1280,1344,1392,1516,800,805,812,824,1,0,1 disablehpd=false cvbscable= overscan=100  monitor_onoff=false logo=osd0,loaded hdmitx=cec3f sdrmode=auto consoleblank=0 enable_wol=0
[    14.551] Build Date: 14 December 2021  02:14:13PM
[    14.551] xorg-server 2:1.20.13-1ubuntu1~20.04.2 (For technical support please see http://www.ubuntu.com/support) 
[    14.551] Current version of pixman: 0.38.4
[    14.551] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[    14.551] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    14.551] (==) Log file: "/var/log/Xorg.0.log", Time: Sun Apr  3 10:50:27 2022
[    14.552] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    14.553] (==) No Layout section.  Using the first Screen section.
[    14.553] (==) No screen section available. Using defaults.
[    14.553] (**) |-->Screen "Default Screen Section" (0)
[    14.553] (**) |   |-->Monitor "<default monitor>"
[    14.555] (==) No device specified for screen "Default Screen Section".
	Using the first device section listed.
[    14.555] (**) |   |-->Device "FBTURBO"
[    14.555] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[    14.555] (==) Automatically adding devices
[    14.555] (==) Automatically enabling devices
[    14.555] (==) Automatically adding GPU devices
[    14.555] (==) Automatically binding GPU devices
[    14.555] (==) Max clients allowed: 256, resource mask: 0x1fffff
[    14.561] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[    14.561] 	Entry deleted from font path.
[    14.561] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist.
[    14.561] 	Entry deleted from font path.
[    14.561] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist.
[    14.561] 	Entry deleted from font path.
[    14.562] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist.
[    14.562] 	Entry deleted from font path.
[    14.562] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist.
[    14.562] 	Entry deleted from font path.
[    14.562] (==) FontPath set to:
	/usr/share/fonts/X11/misc,
	/usr/share/fonts/X11/Type1,
	built-ins
[    14.562] (==) ModulePath set to "/usr/lib/xorg/modules"
[    14.562] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[    14.562] (II) Loader magic: 0x555d833010
[    14.562] (II) Module ABI versions:
[    14.562] 	X.Org ANSI C Emulation: 0.4
[    14.562] 	X.Org Video Driver: 24.1
[    14.562] 	X.Org XInput driver : 24.1
[    14.562] 	X.Org Server Extension : 10.0
[    14.563] (++) using VT number 7

[    14.563] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[    14.564] (II) no primary bus or device found
[    14.564] (II) LoadModule: "glx"
[    14.569] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[    14.584] (II) Module glx: vendor="X.Org Foundation"
[    14.584] 	compiled for 1.20.13, module version = 1.0.0
[    14.584] 	ABI class: X.Org Server Extension, version 10.0
[    14.584] (II) LoadModule: "fbturbo"
[    14.585] (II) Loading /usr/lib/xorg/modules/drivers/fbturbo_drv.so
[    14.586] (II) Module fbturbo: vendor="X.Org Foundation"
[    14.587] 	compiled for 1.20.8, module version = 0.5.1
[    14.587] 	Module class: X.Org Video Driver
[    14.587] 	ABI class: X.Org Video Driver, version 24.1
[    14.587] (II) FBTURBO: driver for framebuffer: fbturbo
[    14.595] (WW) Falling back to old probe method for fbturbo
[    14.595] (II) Loading sub module "fbdevhw"
[    14.595] (II) LoadModule: "fbdevhw"
[    14.595] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[    14.597] (II) Module fbdevhw: vendor="X.Org Foundation"
[    14.597] 	compiled for 1.20.13, module version = 0.0.2
[    14.597] 	ABI class: X.Org Video Driver, version 24.1
[    14.597] (II) FBTURBO(0): using /dev/fb0
[    14.597] (WW) VGA arbiter: cannot open kernel arbiter, no multi-card support
[    14.597] (II) FBTURBO(0): Meson OSD alpha swap enabled
[    14.597] (II) FBTURBO(0): Creating default Display subsection in Screen section
	"Default Screen Section" for depth/fbbpp 24/32
[    14.597] (==) FBTURBO(0): Depth 24, (==) framebuffer bpp 32
[    14.597] (==) FBTURBO(0): RGB weight 888
[    14.597] (==) FBTURBO(0): Default visual is TrueColor
[    14.597] (==) FBTURBO(0): Using gamma correction (1.0, 1.0, 1.0)
[    14.597] (II) FBTURBO(0): hardware: OSD FB (video memory: 77312kB)
[    14.597] (DB) xf86MergeOutputClassOptions unsupported bus type 0
[    14.598] (**) FBTURBO(0): Option "fbdev" "/dev/fb0"
[    14.598] (**) FBTURBO(0): Option "alpha_swap" "true"
[    14.598] (**) FBTURBO(0): Option "SwapbuffersWait" "true"
[    14.598] (II) FBTURBO(0): processor: Unknown
[    14.598] (II) FBTURBO(0): checking modes against framebuffer device...
[    14.598] (II) FBTURBO(0): checking modes against monitor...
[    14.598] (II) FBTURBO(0): Virtual size is 1280x800 (pitch 1280)
[    14.598] (**) FBTURBO(0):  Built-in mode "current"
[    14.598] (==) FBTURBO(0): DPI set to (96, 96)
[    14.598] (II) Loading sub module "fb"
[    14.598] (II) LoadModule: "fb"
[    14.598] (II) Loading /usr/lib/xorg/modules/libfb.so
[    14.600] (II) Module fb: vendor="X.Org Foundation"
[    14.600] 	compiled for 1.20.13, module version = 1.0.0
[    14.600] 	ABI class: X.Org ANSI C Emulation, version 0.4
[    14.636] (II) FBTURBO(0): using backing store heuristics
[    14.642] (II) FBTURBO(0): enabled VFP/NEON optimizations
[    14.642] (==) FBTURBO(0): Backing store enabled
[    14.644] (==) FBTURBO(0): DPMS enabled
[    14.644] (II) FBTURBO(0): no 3D acceleration because the driver has been compiled without libUMP
[    14.644] (II) FBTURBO(0): if this is wrong and needs to be fixed, please check ./configure log
[    14.644] (II) Initializing extension Generic Event Extension
[    14.645] (II) Initializing extension SHAPE
[    14.645] (II) Initializing extension MIT-SHM
[    14.645] (II) Initializing extension XInputExtension
[    14.646] (II) Initializing extension XTEST
[    14.646] (II) Initializing extension BIG-REQUESTS
[    14.646] (II) Initializing extension SYNC
[    14.647] (II) Initializing extension XKEYBOARD
[    14.647] (II) Initializing extension XC-MISC
[    14.647] (II) Initializing extension SECURITY
[    14.647] (II) Initializing extension XFIXES
[    14.647] (II) Initializing extension RENDER
[    14.648] (II) Initializing extension RANDR
[    14.648] (II) Initializing extension COMPOSITE
[    14.649] (II) Initializing extension DAMAGE
[    14.649] (II) Initializing extension MIT-SCREEN-SAVER
[    14.649] (II) Initializing extension DOUBLE-BUFFER
[    14.649] (II) Initializing extension RECORD
[    14.650] (II) Initializing extension DPMS
[    14.650] (II) Initializing extension Present
[    14.650] (II) Initializing extension DRI3
[    14.650] (II) Initializing extension X-Resource
[    14.650] (II) Initializing extension XVideo
[    14.650] (II) Initializing extension XVideo-MotionCompensation
[    14.650] (II) Initializing extension SELinux
[    14.650] (II) SELinux: Disabled on system
[    14.650] (II) Initializing extension GLX
[    14.651] (II) AIGLX: Screen 0 is not DRI2 capable
[    14.986] (II) IGLX: Loaded and initialized swrast
[    14.986] (II) GLX: Initialized DRISWRAST GL provider for screen 0
[    14.986] (II) Initializing extension XFree86-VidModeExtension
[    14.986] (II) Initializing extension XFree86-DGA
[    14.986] (II) Initializing extension XFree86-DRI
[    14.987] (II) Initializing extension DRI2
[    15.055] (II) config/udev: Adding input device WaveShare WS170120 (/dev/input/event5)
[    15.055] (**) WaveShare WS170120: Applying InputClass "libinput touchscreen catchall"
[    15.055] (II) LoadModule: "libinput"
[    15.055] (II) Loading /usr/lib/xorg/modules/input/libinput_drv.so
[    15.061] (II) Module libinput: vendor="X.Org Foundation"
[    15.061] 	compiled for 1.20.4, module version = 0.29.0
[    15.061] 	Module class: X.Org XInput Driver
[    15.061] 	ABI class: X.Org XInput driver, version 24.1
[    15.061] (II) Using input driver 'libinput' for 'WaveShare WS170120'
[    15.061] (**) WaveShare WS170120: always reports core events
[    15.061] (**) Option "Device" "/dev/input/event5"
[    15.061] (**) Option "_source" "server/udev"
[    15.126] (II) event5  - WaveShare WS170120: is tagged by udev as: Touchscreen
[    15.126] (II) event5  - WaveShare WS170120: device is a touch device
[    15.127] (II) event5  - WaveShare WS170120: device removed
[    15.176] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.1/1-1.1:1.0/0003:0EEF:0005.0001/input/input5/event5"
[    15.176] (II) XINPUT: Adding extended input device "WaveShare WS170120" (type: TOUCHSCREEN, id 6)
[    15.176] (**) Option "AccelerationScheme" "none"
[    15.176] (**) WaveShare WS170120: (accel) selected scheme none/0
[    15.176] (**) WaveShare WS170120: (accel) acceleration factor: 2.000
[    15.176] (**) WaveShare WS170120: (accel) acceleration threshold: 4
[    15.239] (II) event5  - WaveShare WS170120: is tagged by udev as: Touchscreen
[    15.239] (II) event5  - WaveShare WS170120: device is a touch device
[    15.241] (II) config/udev: Adding input device WaveShare WS170120 (/dev/input/mouse2)
[    15.241] (II) No input driver specified, ignoring this device.
[    15.241] (II) This device may have been added with another device file.
[    15.242] (II) config/udev: Adding input device Logitech M570 (/dev/input/event3)
[    15.242] (**) Logitech M570: Applying InputClass "libinput pointer catchall"
[    15.242] (II) Using input driver 'libinput' for 'Logitech M570'
[    15.242] (**) Logitech M570: always reports core events
[    15.242] (**) Option "Device" "/dev/input/event3"
[    15.242] (**) Option "_source" "server/udev"
[    15.245] (II) event3  - Logitech M570: is tagged by udev as: Mouse Trackball
[    15.245] (II) event3  - Logitech M570: device set to 540 DPI
[    15.245] (II) event3  - Logitech M570: device is a pointer
[    15.245] (II) event3  - Logitech M570: device removed
[    15.288] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.2/1-1.2:1.2/0003:046D:C52B.0004/0003:046D:1028.0007/input/input3/event3"
[    15.288] (II) XINPUT: Adding extended input device "Logitech M570" (type: MOUSE, id 7)
[    15.288] (**) Option "AccelerationScheme" "none"
[    15.288] (**) Logitech M570: (accel) selected scheme none/0
[    15.288] (**) Logitech M570: (accel) acceleration factor: 2.000
[    15.288] (**) Logitech M570: (accel) acceleration threshold: 4
[    15.291] (II) event3  - Logitech M570: is tagged by udev as: Mouse Trackball
[    15.291] (II) event3  - Logitech M570: device set to 540 DPI
[    15.291] (II) event3  - Logitech M570: device is a pointer
[    15.292] (II) config/udev: Adding input device Logitech M570 (/dev/input/mouse0)
[    15.293] (II) No input driver specified, ignoring this device.
[    15.293] (II) This device may have been added with another device file.
[    15.294] (II) config/udev: Adding input device Logitech M570 (/dev/input/event4)
[    15.294] (**) Logitech M570: Applying InputClass "libinput pointer catchall"
[    15.294] (II) Using input driver 'libinput' for 'Logitech M570'
[    15.294] (**) Logitech M570: always reports core events
[    15.294] (**) Option "Device" "/dev/input/event4"
[    15.294] (**) Option "_source" "server/udev"
[    15.297] (II) event4  - Logitech M570: is tagged by udev as: Mouse Trackball
[    15.297] (II) event4  - Logitech M570: device set to 540 DPI
[    15.297] (II) event4  - Logitech M570: device is a pointer
[    15.297] (II) event4  - Logitech M570: device removed
[    15.340] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.2/1-1.2:1.2/0003:046D:C52B.0004/0003:046D:1028.0008/input/input4/event4"
[    15.340] (II) XINPUT: Adding extended input device "Logitech M570" (type: MOUSE, id 8)
[    15.340] (**) Option "AccelerationScheme" "none"
[    15.340] (**) Logitech M570: (accel) selected scheme none/0
[    15.340] (**) Logitech M570: (accel) acceleration factor: 2.000
[    15.340] (**) Logitech M570: (accel) acceleration threshold: 4
[    15.342] (II) event4  - Logitech M570: is tagged by udev as: Mouse Trackball
[    15.342] (II) event4  - Logitech M570: device set to 540 DPI
[    15.342] (II) event4  - Logitech M570: device is a pointer
[    15.344] (II) config/udev: Adding input device Logitech M570 (/dev/input/mouse1)
[    15.344] (II) No input driver specified, ignoring this device.
[    15.344] (II) This device may have been added with another device file.
[    15.345] (II) config/udev: Adding input device HID 046a:002b (/dev/input/event1)
[    15.345] (**) HID 046a:002b: Applying InputClass "libinput keyboard catchall"
[    15.345] (II) Using input driver 'libinput' for 'HID 046a:002b'
[    15.345] (**) HID 046a:002b: always reports core events
[    15.345] (**) Option "Device" "/dev/input/event1"
[    15.345] (**) Option "_source" "server/udev"
[    15.348] (II) event1  - HID 046a:002b: is tagged by udev as: Keyboard
[    15.348] (II) event1  - HID 046a:002b: device is a keyboard
[    15.348] (II) event1  - HID 046a:002b: device removed
[    15.380] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.3/1-1.3:1.0/0003:046A:002B.0005/input/input1/event1"
[    15.380] (II) XINPUT: Adding extended input device "HID 046a:002b" (type: KEYBOARD, id 9)
[    15.380] (**) Option "xkb_model" "pc105"
[    15.380] (**) Option "xkb_layout" "us"
[    15.385] (II) event1  - HID 046a:002b: is tagged by udev as: Keyboard
[    15.385] (II) event1  - HID 046a:002b: device is a keyboard
[    15.389] (II) config/udev: Adding input device HID 046a:002b (/dev/input/event2)
[    15.389] (**) HID 046a:002b: Applying InputClass "libinput keyboard catchall"
[    15.389] (II) Using input driver 'libinput' for 'HID 046a:002b'
[    15.389] (**) HID 046a:002b: always reports core events
[    15.389] (**) Option "Device" "/dev/input/event2"
[    15.389] (**) Option "_source" "server/udev"
[    15.394] (II) event2  - HID 046a:002b: is tagged by udev as: Keyboard
[    15.394] (II) event2  - HID 046a:002b: device is a keyboard
[    15.395] (II) event2  - HID 046a:002b: device removed
[    15.412] (II) libinput: HID 046a:002b: needs a virtual subdevice
[    15.412] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.3/1-1.3:1.1/0003:046A:002B.0006/input/input2/event2"
[    15.412] (II) XINPUT: Adding extended input device "HID 046a:002b" (type: MOUSE, id 10)
[    15.412] (**) Option "AccelerationScheme" "none"
[    15.412] (**) HID 046a:002b: (accel) selected scheme none/0
[    15.412] (**) HID 046a:002b: (accel) acceleration factor: 2.000
[    15.412] (**) HID 046a:002b: (accel) acceleration threshold: 4
[    15.417] (II) event2  - HID 046a:002b: is tagged by udev as: Keyboard
[    15.417] (II) event2  - HID 046a:002b: device is a keyboard
[    15.419] (II) config/udev: Adding input device cec_input (/dev/input/event0)
[    15.419] (**) cec_input: Applying InputClass "libinput keyboard catchall"
[    15.419] (II) Using input driver 'libinput' for 'cec_input'
[    15.419] (**) cec_input: always reports core events
[    15.419] (**) Option "Device" "/dev/input/event0"
[    15.419] (**) Option "_source" "server/udev"
[    15.421] (II) event0  - cec_input: is tagged by udev as: Keyboard
[    15.421] (II) event0  - cec_input: device is a keyboard
[    15.421] (II) event0  - cec_input: device removed
[    15.440] (**) Option "config_info" "udev:/sys/devices/virtual/input/input0/event0"
[    15.440] (II) XINPUT: Adding extended input device "cec_input" (type: KEYBOARD, id 11)
[    15.440] (**) Option "xkb_model" "pc105"
[    15.440] (**) Option "xkb_layout" "us"
[    15.442] (II) event0  - cec_input: is tagged by udev as: Keyboard
[    15.442] (II) event0  - cec_input: device is a keyboard
[    15.466] (**) HID 046a:002b: Applying InputClass "libinput keyboard catchall"
[    15.467] (II) Using input driver 'libinput' for 'HID 046a:002b'
[    15.467] (**) HID 046a:002b: always reports core events
[    15.467] (**) Option "Device" "/dev/input/event2"
[    15.467] (**) Option "_source" "_driver/libinput"
[    15.467] (II) libinput: HID 046a:002b: is a virtual subdevice
[    15.467] (**) Option "config_info" "udev:/sys/devices/platform/ff500000.dwc3/xhci-hcd.0.auto/usb1/1-1/1-1.3/1-1.3:1.1/0003:046A:002B.0006/input/input2/event2"
[    15.467] (II) XINPUT: Adding extended input device "HID 046a:002b" (type: KEYBOARD, id 12)
[    15.467] (**) Option "xkb_model" "pc105"
[    15.467] (**) Option "xkb_layout" "us"
root@odroid:~#

Touch rotation

Depending  on  how  you  want  to rotate  the  display, you  must  enter  the following values :
90°-Option "CalibrationMatrix" "0 1 0 -1 0 1 0 0 1"
180°-Option "CalibrationMatrix" "-1 0 1 0 -1 1 0 0 1"
270°-Option "CalibrationMatrix" "0 -1 1 1 0 0 0 0 1"

Enabling the On-Screen-Keyboard

  • In applications, where you don't want to use an external keyboard you have the possibility to use an "On-Screen-Keyboard" which could be controlled via the Touch-Screen.

Switch-On the On-Screen-Keyboard on Ubuntu-Mate

  • On Ubuntu-Mate the On-Screen-Keyboard is already installed. You can find it in the ‘Universal Access’ menu. In this menu you find the application "Onboard" -> a click on this menu-point activates the On-Screen-Keyboard.

Adding support for ARM 32-bit code execution 

odroid64:$ sudo dpkg --add-architecture armhf

odroid64:$ sudo apt-get update

apt install libc6:armhf

apt install libx11-6:armhf

apt install libfreetype6:armhf

apt install libxext6:armhf

apt install libasound2:armhf

Changing FDT (Flattened Device Tree) to support second UART-Interface for MIDI

Installation of the device tree compiler (dtc)

$ apt install device-tree-compiler

check if second UART is allready enabled

fdtget /media/boot/meson64_odroidn2.dtb /serial@ffd24000 status
 
# returns
disabled
  • "disabled" means that the second native uart is disabled

enabling the second UART

vor UBUNTU 20.04

$ fdtput -t s /media/boot/meson64_odroidn2.dtb /serial@ffd24000 status "okay"
$ fdtget /media/boot/meson64_odroidn2.dtb /serial@ffd24000 status
 
# returns
okay

reboot
  • After the reboot you can list the available UARTs by typing the following command
ls -al /dev/ttyS?
 
# returns
crw--w---- 1 root tty     238, 0 May 28 18:36 /dev/ttyS0
crw-rw---- 1 root dialout 238, 1 Jan 29  2018 /dev/ttyS1
  • Two UARTs are available - /dev/ttyS0 for console usage and /dev/ttyS1 which we will use for MIDI

mit UBUNTU > 20.04

Enabling 31250 UART-Baud-Rate for Midi-Usage

  • The baud-rate 31250 which is used for MIDI-traffic is normally NOT supported on standard UART drivers.
  • We have to tweek the UART-Kernel-driver for supporting this baud rate. This sounds like a complicated action, but it isn't really complicated - take a look on this article in the Odroid-Magazine -> ODROID-N2 UART Custom Baud Rate for MIDI
linux/drivers/amlogic/uart/meson_uart.c

static void meson_uart_change_speed(struct uart_port *port, unsigned long baud)
{
u32 val;
struct meson_uart_port *mup = to_meson_port(port);
struct platform_device *pdev = to_platform_device(port->dev);

while (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_EMPTY))
cpu_relax();

#ifdef UART_TEST_DEBUG
if (port->line != 0)
baud = 115200;
#endif

// this part is added.
// trace_printk() is not neccesarry, it is just for debugging.
trace_printk("Your baudrate: %ld\n", baud);
if(baud == 38400)
{
baud = 31250;
trace_printk("Change to %ld\n", baud);
}

Cross-Compiling or compiling the Kernel natively (on the Odroid-N2 itself)

  • You have the possibility to compile the Kernel external (e.g. on your Desktop-PC/Laptop) where you have to install the Cross-Compiler-Toolchain and the other build utilities) or directly on the Odroid itself.
  • I am a fan of doing it directly on the Odroid-N2 itself. Therefore I describe this procedure first.

compiling the Kernel natively on the Odroid-N2

getting the Kernel-Sources

  • changing the user to be "root"
$ sudo su
--> enter your root password

Attention: Be careful - the root-user can do really everything on the system - also damaging the running OS

  • going to the directory where you want to build the kernel
$ cd /usr/src/
  • install the source code version control system software "git":
$ apt install git
  • going into the kernel-root-path
$ cd /usr/src/linux/
  • getting the kernel-sources (cloning) from github:
$ git clone --depth 1 https://github.com/hardkernel/linux.git -b odroidg12-4.9.y

configuring the kernel

  • configuring the base configuration of the kernel
$ make odroidg12_defconfig
  • edit the uart-driver with an editor of your choice - for me it's the editor "vi" -> $ vi /usr/src/linux/drivers/amlogic/uart/meson_uart.c
  • alter there the function meson_uart_change_speed to the following:
static void meson_uart_change_speed(struct uart_port *port, unsigned long baud)
{
        u32 val;
        struct meson_uart_port *mup = to_meson_port(port);
        struct platform_device *pdev = to_platform_device(port->dev);

        while (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_EMPTY))
                cpu_relax();

#ifdef UART_TEST_DEBUG
        if (port->line != 0)
                baud = 115200;
#endif

// this part is added.
// trace_printk() is not neccesarry, it is just for debugging.
        trace_printk("Your baudrate: %ld\n", baud);
        if(baud == 38400)
        {
                baud = 31250;
                trace_printk("Change to %ld\n", baud);
        }
  • save your file!

additional kernel-config

  • if you want to add other stuff to the kernel config you can do this by using the command "make menuconfig"
  • if "make menuconfig" could not be startet because auf missing curses-support you have to install the libncurses-dev package
$ apt install libncurses-dev

$ make menuconfig

compiling the kernel

$ make -j7

install kernel-modules

$ make modules_install

install new kernel and the new flattened device tree

$ cp -f arch/arm64/boot/Image.gz arch/arm64/boot/dts/amlogic/meson64_odroidn2.dtb /media/boot/
$ sync
$ reboot


make a MIDI device out of the ttyS1 by using ttyMIDI

gcc ttymidi.c -o ttymidi -lasound -pthread
  • Warning when compiling ttymidi out-of-the-box:
ttymidi.c:533:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
 main(int argc, char** argv)
  • you can avoid this "compiler-hint" just by adding an "int" bevor "main"
change line 533 to:

int main(int argc, char** argv)

ttyMIDI Aufruf

$ ./ttymidi -s /dev/ttyS1 -b 38400

Adding ADC (Audio-Input) to Odroid N2 - EXPERIMENTAL

> Main Page > Piano Expander based on Pianoteq and Odroid-N2

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