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Re: Braille devices (the problem was DOSemu)

Hi all,
In my specific case where I wasn't able to run a Alva ABT280, this was the
hardware problem + this should be the solution:
- the problem: the DB9 connector on the rear panel didn't have the function
of serial connection for the device; so the only way for the ABT280 was
the parallel port. (No spex from factory, as Nicolas Pitre explained).
But Dosgate, see http://www.cs.unibo.it/~zinie/dosgate uses DOSemu, and
- The solution was/is: the implementation of DOSemu so that I was able to
run C:\ABT280.EXE 1 (corresponds to lpt1) and that's all,
then returning to Linux.

it is not promised to me, but I will ask again for confirmation: a student
of the KU-Leuven should start the DOSemu implementation, but not before
November......... During this time, I must try a non-braille solution:
Screader + Festival fails.
I do also had contact with the developer of Speakup
(http://www.linux-speakup.org) for developing his screen reader for usage
in combi with software-speech (Mbrola, TuxTalk, not Festival: too
big/slow/75 % of processor usage for him).

--I'm not on this list, for reactions send it in CC to my address:
olr@xs4all.be or mail@audiobraille.org

Grtnx, Osvaldo La Rosa

---In answer to your session:---
On 2000-08-19 nico@cam.org said:
   >cc: VZW AUDIO/BRAILLE <olr@xs4all.be>, debian-devel@lists.debian.
   >> [CCed to linux-kernel, as IMO the best idea would be to implement
   >>this at   kernel level]
   >> On Wed, 16 Aug 2000, VZW AUDIO/BRAILLE wrote:
   >> > Hi, I have on one pc the very great chance to use Debian 2.1
   >>with a  > hardware braille-display. But actually on another pc I'm
   >>suffering from  > the refusal of my old braille display (not
   >>brltty supported) to let  > me work under Deb. So on pc1 I've a
   >>great pleasure to work, on another  > nothing more than
   >frustration! >
   >> [...]
   >> I've seen the request for braille device support during
   >>installation here  on debian-devel for many times, and IMO the
   >>best approach would be to  support these devices at kernel level.
   >>The reason for this is that a  daemon approach would compromise
   >>system security, as some (luckily not too  many) braille devices
   >>have special interface cards which require hardware  access. Also,
   >>a daemon has to be started in order to be useful, so that  you
   >cannot see anything if the boot fails. >
   >> Comments?
   >First, let me say that I'm actually the maintainer of BRLTTY
   >(http://www.cam.org/~nico/brltty) and used it most everyday on
   >Linux for nearly six years now.  I would like to take this
   >opportunity to answer some questions and kill some common myths
   >that I keep encountering over and over.  All this rambling also
   >applies to other packages similar to BRLTTY...
   >Braille Display Support
   >BRLTTY is quite modular and actually support over 10 different
   >brands of braille display families.  Adding another is just a
   >matter of having the protocol specification from the manufacturer
   >(you know the classic problem?) and someone to implement it.  So
   >the user space vs kernel space argument is a non-issue for "my
   >display isn't supported" statements. The scarce braille displays
   >requireing a special interface card are mostly using firmware on
   >the card that emulates a VGA text display, or that retrieve data
   >directly from the video memory of your VGA card, in order to send
   >it directly to the braille display thus not relying on software
   >support at all.  In the case where kernel support is absolutely
   >required, only the raw low-level communication support must be in
   >the kernel, nothing more. System Security
   >BRLTTY only requires access to /dev/vcsa0, /dev/tty0 and /dev/ttyS0.
   >It is intended to be used by the person at the console only and
   >that person usually has root access.  If you don't want to run
   >BRLTTY as root, you just have to adjust permissions on the above
   >devices. Braille-Enabled Linux Installation
   >The fastest and easiest way to have Linux installed for a blind
   >person might still consist of a sighted person assisting the
   >instalation up to the activation of BRLTTY.  Has anyone been able
   >to install NT or W2K with braille support during the OS
   >installation anyway? But... since Linux is also about freedom...
   >Linux installation may even be done with BRLTTY on bootdisks!  I've
   >installed many version of Red Hat in the past without any sighted
   >help and also got reports of success stories for Slackware and
   >Debian as well. The current development version of BRLTTY contains
   >a mini-howto on installation bootdisks hacking.  I encourage every
   >interested distributors to have a look at it and maintain a special
   >bootdisk for braille-enabled Linux installation.  I did it for me,
   >the recipee is available, but don't ask me to do it for you please.
   >Here again, the kernel solution isn't much of an advantage because
   >you'll typically have BRLTTY reside on an initial ramdisk (initrd)
   >which contents is executed before any kind of installation
   >procedure.  When the loading of the initrd fails, it'll most
   >probably be the case for the kernel as well, and the blind person
   >will remain clueless either ways.  The "in the kernel approach"
   >doesn't bring an advantage worth its cost. Since BRLTTY uses
   >/dev/vcsa0, all kernel messages are available from the console's
   >scrollback function.  Even the BIOS boot messages can be consulted
   >that way! Conclusion ----------
   >BRLTTY is a daemon simply because its job can be done outside the
   >kernel. It has been like that since 1995 and you know what? the
   >first old version from 1995 still can run unmodified on a 2.4.x
   >kernel.  So please always look at what can be done in user space
   >before advocating kernel solutions. Putting this into the kernel
   >would simply be a maintenance overhead. My pay job consists of
   >kernel hacking and I also maintain kernel support for the StrongARM
   >SA1100 in my free time. Therefore I'm quite familiar with it and
   >don't think adaptive applications belongs there.  Some will argue
   >that Speakup is in kernel space but speech is a different matter
   >than braille, and I'm still not convinced anyway. As a sidenote,
   >people used to their good old DOS TSR for their braille/speech
   >hardware could have a look at DOSgate (http://www.cs.unibo.
   >it/~zinie/dosgate/).  It lets you access the Linux console
   >transparently through a dosemu session using your DOS adaptation
   >tools.  This might be an alternative to the lack of native Linux
   >support for some hardware... or lack of good enough Linux screen
   >reader package for one's taste. Nicolas


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