Date: Mon, 3 Feb 1997 13:39:27 +1000 (AEST) From: Jason White To: jdashiel AT eagle1 DOT eaglenet DOT com cc: opendos AT mail DOT tacoma DOT net Subject: Re: [opendos] Accessibility of OpenDOS with braille and speech output devices In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-opendos AT mail DOT tacoma DOT net Precedence: bulk I think an environmental variable that could be set in config.sys or autoexec.bat for either BIOS calls or direct screen writing would be a suitable solution. Incidentally, programmes that write text data directly into the video memory are only a problem for speech synthesizer users, who would lose the benefit of having the output read to them automatically. It is normally quite possible to issue explicit keyboard commands to the screen reading programme in order to read text that has been written directly to video memory. Indeed, the more advanced of these programmes use sophisticated monitoring techniques in an attempt to detect changes on the screen that are not due to BIOS calls. I think they intercept the computer's timer and examine the video memory on a regular basis, but I am not a technical expert and hence do not know the details. Braille display devices are not affected, so far as I know, by how text is sent to the screen. My braille display functions equally well regardless of whether or not the system is using the BIOS for output. However, for speech synthesizer users, it is obviously not convenient to have to give specific commands (normally by pressing keys on the keyboard that are under the control of the access software) whenever they want to read a prompt or message displayed by the operating system. Therefore, allowing the writing technique to be selected by the user as a global configuration option would be the best solution for all, including those who are using computers that are not compatible with pc's as far as their video services are concerned. Regards, Jason White.