Translation(s): English - Português (Brasil)
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Passing boot parameters
The exact details on how to append boot parameters should be checked in the x86 UEFI case, see section "The Boot Screen" of the installation manual, and use
kvm -soundhw pcspk -cdrom image.iso -bios OVMF.fd
to check what is working.
Braille
Starting from version 0.9.1-4, debian's qemu-kvm has support for a virtual braille device. That means that you can very easily (i.e. without any braille hardware) test the debian installer support for braille devices by just installing brltty-x11 (at least version 3.10~r3715-1) and running:
$ /sbin/brltty -b xw -x no -A auth=none,host=127.0.0.1:1 $ BRLAPI_HOST=127.0.0.1:1 kvm -usbdevice braille -cdrom mini.iso
The first command will show a window that displays what would be displayed on a braille device. If you have issues with it, add -l debug -n -e to the command line to get more debugging details. If it's complaining about the font, try to append -B font='-*-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1' or even -B font='-*-fixed-*-*-*-*-*-*-*-*-*-*-iso8859-1' .
The second command starts the installer (without harddisk so only the first few installation steps can be tested). If qemu/kvm complains that it doesn't find the "braille" backend, it was probably built without brlapi support. Make sure to have the libbrlapi devel package installed when building qemu/kvm. The isolinux boot menu does not show on the braille device. Just "blindly" hit enter.
After the installer has booted you should see:
- the newt frontend being used without framebuffer
- the language list limited to languages supported by the plain Linux console (accented characters may not show correctly in the brltty window, that's a known limitation of the virtual braille device being shown)
- the currently selected line from the language list visible in the brltty window
- changing selections or tabbing to buttons reflected in the brltty window
- If the braille window is still showing the version of BrlTTY, just click on it to bypass that greeting message.
Serial braille support
To test the serial device support, replace
-usbdevice braille
with
-serial braille
and append
brltty=bm,ttyS0
to the kernel command line.
braille hotplug support
To test hotplug support (new in wheezy with brltty 4.2-9), replace
-usbdevice braille
with
-usbdevice mouse
to remove the braille device but keep the USB tree initialized by qemu/kvm, and after d-i startup, press ctrl-alt-2 to get into the qemu/kvm console, and there type
chardev-add braille,id=brl device_add usb-braille,chardev=brl
or more simply, with old versions of qemu/kvm:
and use ctrl-alt-1 to switch back to the installer. Debconf should get killed and restart in text mode.
After installation
On reboot into the newly-installed system, nothing more should be needed to get braille output again. This should work when installing without a network mirror too. If the (gnome) graphical desktop task was chosen, orca should get started to read gdm's chooser, and sound effects should be enabled. The user created during d-i should get orca and sound effects enabled in its session too.
Low vision
There is a high contrast them which can be enabled by adding
theme=dark
to the kernel command line. This is supported by both the "newt" and "gtk" frontends. TODO: the low vision parameter should get applied to gdm and the created user.
Starting from Debian installer Stretch Alpha 5, Zoom can be obtained by pressing control +/-.
TODO: bigger mouse cursor
Speech
Hardware Speech
Run
kvm -serial stdio -cdrom image.iso
choose the GTK installer, and append
speakup.synth=dummy
to the kernel command line. You will then get on stdio what would be spoken.
Software Speech
To test software speech synthesis, simply pass -soundhw ac97 , and select speech synthesis in the boot menu (last item, s shortcut). As soon as the first debconf question you should get spoken feedback from the sound board.
Also test with EFI (requires ovmf from non-free):
kvm -soundhw ac97 -cdrom image.iso -bios OVMF.fd
Starting with Stretch alpha6, also test with several sound boards:
kvm -soundhw all -cdrom image.iso
This should trigger asking for confirmation of the sound card to be used, by pressing the enter key, and this should be recorded in /etc/default/espeakup on the installed system.
One can easily check that the proper card is being used by pressing capslock-2 or capslock-1 to change the audio level, and use e.g.
ALSA_CARD=1 amixer
to check that the level of the proper card (here the second, indexed 1) is getting changed.
After installation
On reboot into the newly-installed system, nothing more should be needed to get output again. This should work when installing without a network mirror too. If the (gnome) graphical desktop task was chosen, orca should get started to read lightdm's chooser, and sound effects should be enabled. The user created during d-i should get orca and sound effects enabled in its session too.