Full screen Presentation (Waswhere am I on the screen? )

Full screen Presentation (Waswhere am I on the screen? )

[Martin McCormick]

Before I started using speakup right around
Newyear's Day, I was using a screen reader I wrote in assembler,
starting in the very late eighties. I seem to remember that some
forms of ansi.sys in DOS would produce multiple prints of
whatever was being sent to the screen. Do any of you remember
hooking interrupt 0x10 better known as the video BIOS interrupt?
I think the multiple prints consisted of one valid character of
the desired color plus another just before or just after that
had the same foreground and background attributes making it
invisible on the screen for sighted users, but you could sure
hear it if you were ignoring attributes and just catching the
ASCII value in the lower 8 bits. What we are dealing with now is
more likely the same problem. I used 3ansi.sys to get sensable
output in general DOS and MSKermit as the VT100 emulator which
normally gave clear output. I always think it is best to get
readable output as it comes in whenever possible and MSKermit
did cause the FreeBSD installer and similar full-screen programs
to behave fairly well as long as the output from the program
came in sequentially.

	What I hear now is a slow and dragged out presentation
as a new screen comes in and a nice snappy normal presentation 
upon pressing the keypad Plus to review the screen. Speakup is
simply trying to read what it is receiving which I believe is a
lot of double-printing as the terminal emulation paints a new
screen. I guess it comes down to figuring out whether existing
tools can be configured to produce clear speech as new screens
come in or if I need to get busy on some sort of filter. I think
it was more dumb luck than anything else, but MSKermit's VT100
emulator did a great job of handling the installer program's
output.

	I've got about 8 systems to do this installation on so
everything that makes it smoother is greatly appreciated.

	So far, the change from my old system to speakup has
been fantastic. The problem with the full-screen installer and
VT100 emulation is the only thing that, so far, used to work
better and is pretty rough at this time.

	I don't think the FreeBSD sysinstall program is doing
anything that out of the ordinary but it probably uses a lot of
curses-based library routines for control. Trying to  decipher
the sound and fury of the screen output has prompted a few
curses of my own. Hmm. Is this still the same screen again or
did I go to the next screen? I think it said something about
rebooting. Is this what Martian sounds like?

Martin McCormick WB5AGZ  Stillwater, OK 
Systems Engineer
OSU Information Technology Department Telecommunications Services Group

Re: Full screen Presentation (Waswhere am I on the screen? )

[trev.saunders]

Hi,

well for that many installs apply some D D?

Trev

Re: Full screen Presentation (Waswhere am I on the screen? )

[Martin McCormick]

	Here is an update. My shell uses Linux as the default
TERM variable. This works normally in the shell and when using
ssh to other Unix hosts. If I use ckermit's terminal window to
make a serial line connection to a system, I am getting some of
the same weirdness I was getting in the installer program. This
means that  I am not making the serial connection properly to
begin with. I bet as soon as I fix that problem, most of the
others will go away.

Martin McCormick

Re: Full screen Presentation (Waswhere am I on the screen? )

[Chris Brannon]

> 	Here is an update. My shell uses Linux as the default
> TERM variable. This works normally in the shell and when using
> ssh to other Unix hosts.

Right.  The "linux" terminal type is more or less the same as a VT100.
If your terminal type is linux, and you connect via C-Kermit to something
that wants to talk to a VT100, then you shouldn't have any problems
with terminal emulation.

-- Chris

Re: Full screen Presentation (Waswhere am I on the screen? )

[Martin McCormick]

Chris Brannon writes:
> Right.  The "linux" terminal type is more or less the same as a VT100.
> If your terminal type is linux, and you connect via C-Kermit to something
> that wants to talk to a VT100, then you shouldn't have any problems
> with terminal emulation.

	I found the likely cause of the weirdness. It is a
timing issue. I did an experiment in which I started out with a
serial line speed of  38400 baud and the performance of the
speech was fairly normal. I then dropped the line speed to 600
baud and every single word was spelled. This is not the old
speakup contention issue which has been fixed for quite a while.
Instead, this is an issue in which speakup must decide when to
process a bunch of letters in to a word. There is a timer that
starts each time a character is received and lasts for a small
fraction of a second. If more text arrives during that time, it
is buffered. When the timer does time out, speakup has a chance
to form a word out of this newly-arrived text.

	In this day and age, 600 baud is about 60 characters per
second which is apparently long enough for the timer to think
that someone is sending single characters rather than whole
blocks of text.

The higher the speed, the better the speech. At 9600 baud which
is the speed of the FreeBSD serial console, speech starts to get
a little rough. I imagine that output from the installer program
is a bit bursty which makes for some weird speech. I seem to
recall reading about a timer one can set in speakup which may be
the one to tweak.

	Normally, this is not necessary but the data are flowing
in more slowly. Also, there may be little breaks in the serial
stream as even at 57400, there is a bit of an odd cadence to the
speech as it comes in.

	Thanks for everybody's help.

Martin McCormick WB5AGZ  Stillwater, OK 
Systems Engineer
OSU Information Technology Department Telecommunications Services Group