And this is why the Dectalk Express often is set to use xon-xoff -- at least under windows. on Friday 07/25/2008 Samuel Thibault(samuel.thibault at ens-lyon.org) wrote > Hello, > > I guess it may have to go somewhere in the documentation. > > Kerry Hoath, le Fri 25 Jul 2008 18:49:37 +0800, a ?crit : > > I have no idea whether speakup supports the kernel scrollback buffer which > > relys on storing text in spare video memory. > > It doesn't currently, due to kernel interface limitations. > > > Ok so what do you do from a Linux perspective? Block console output until > > the synth raises rts? > > That is what we are doing currently, by stopping the consoles (just like > if you pressed control-S or the scroll lock key). > > > How long should that blokc happen for? > > Until the synth has eaten some data > > > What if rts never goes high again? > > Should the console freeze forever thereby introducing the possibility of a > > denial of service attack or should speakup give up and assume synth not > > present? > > Speakup currently does the latter: after a few "full_time" timeouts, > speakup considers the synth to be dead, and thus restart the consoles. > > > How long should this process take given that people run their synthesizers > > at different speeds? > > Interesting question, I guess full_time should take into account the > speed. > > > Does the screen stop scrolling for a sighted person and does the console > > file descriptor ever block for them? > > Yes. > > > I certainly would like to see the problem solved; however the problem is not > > as simple as blocking console output when the synthesizer handshakes off. > > It is not simple indeed, but it's implemented and does work to our > knowledge (William usually tests it with his ltlk for instance). We > haven't yet figured out why it doesn't for the dectalk express. > > > I also notice many cables for the dectalk distress either have bad wiring or > > the firmware in the device doesn't even handshake reliably. > > That would explain it. > > Samuel > _______________________________________________ > Speakup mailing list > Speakup at braille.uwo.ca > http://speech.braille.uwo.ca/mailman/listinfo/speakup -- Your life is like a penny. You're going to lose it. The question is: How do you spend it? John Covici covici at ccs.covici.com
