[Blindapple] Emulating Echo

Jayson Smith ratguy at bellsouth.net
Thu Jul 28 20:09:18 EDT 2005


Hi,
I don't think that would work either, saddly.  I don't think the Cricket
takes as its input a text stream, but rather, once again, low level signals
for controlling the LPC chip inside the synthesizer.  If you unplug a
Cricket from the computer while it's talking, speech stops instantly.  Same
thing happens if you Ctrl-Reset while speech is going on.  Also, as far as I
know, nobody ever talked about using the Cricket as a generic serial voice
device, not with Textalker.  And if the Cricket had the text-to-speech logic
built-in, as it would have to do to be used as a generic serial voice
device, then they could have probably created a much smaller version of
Textalker specificly for the Cricket.  As far as I know they never did.  So
as far as I can tell, the Cricket, like the Echo, is just a dumb device
which contains only the required hardware, but no TTS logic.  That logic is
contained within the Textalker software.  What I mean by TTS logic is that
software/firmware which converts normal, human-readable text into phonemic
representation and then converts those phonemes into control signals for a
hardware synthesis chip to make noise.
Jayson.

----- Original Message -----
From: "Aaron Howell" <aaron at kitten.net.au>
To: "Blind Apple Discussions" <blindapple at jaybird.no-ip.info>
Sent: Thursday, July 28, 2005 7:40 PM
Subject: Re: [Blindapple] Emulating Echo


> Guys,
> Has anyone thought that it might be easier to emulate a cricket than an
echo?
> That way you're dealing with a serial interface, rather than an unknown
quantity in how to talk to the synth itself.
> Then you'd just need code to strip out the control codes, and send the
resultant text to a text file, or something.
> You still wouldn't be able to play space invaders under a2, because that
relies on apple sound,
> but you might be able to use other speech enabled software.
> Regards
> Aaron
> On Thu, Jul 28, 2005 at 07:30:42PM -0400, Jayson Smith wrote:
> > Hi,
> > Actually, this might be quite tricky.  Because what Textalker is going
to
> > send to the slot where the Echo is located certainly won't be the actual
> > text to be spoken, and probably not even the phonemic representation.
> > What's probably being sent is some form of very low level signaling to
tell
> > the LPC chip what noises to make when.  If you remember, on a real
Apple,
> > whatever the Apple does comes to a dead hault when the Echo is speaking.
> > This is probably because Textalker is taking up the processor time by
> > converting the printed words into phonemes, then converting the phonemes
> > into the low level signals for the LPC chip, then sending those signals
to
> > the card itself.
> > Jayson.
> >
> > ----- Original Message -----
> > From: "Tony Baechler" <tony at baechler.net>
> > To: "Blind Apple Discussions" <blindapple at jaybird.no-ip.info>
> > Sent: Thursday, July 28, 2005 10:08 AM
> > Subject: [Blindapple] Emulating Echo
> >
> >
> > > Hi.  Is there a way of finding out what it sends to the slot to detect
> > > whether there is a real Echo or not?  I tried various tricks to find
out
> > > but as yet have been unsuccessful.  Obviously I know it sends
something
> > > because that is how the Doubletalk knows when to switch.  Is there a
way
> > to
> > > patch Textalker to only look for a card in slot 1?  I think I am
> > reasonably
> > > close to making A2 simulate an Echo but I need a way to trick
Textalker
> > > into sending to slot 1 even though there is no Echo there.  I know
there
> > is
> > > a way to do this with the older versions, but what about the 3.1 APH
> > > series?  I believe that even though we can't really ever use a real
Echo
> > > under emulation, it can be simulated fairly easily.  I played with
this a
> > > little and looked at the C source and it looks simple enough.  Aalas,
if
> > A2
> > > only emulated sound!  However, if I can get something going under A2,
it
> > > might be possible to make it work with a better emulator.  Please, if
you
> > > know any C programmers, contact me!  This would take a good programmer
> > very
> > > little time to do since I think I know what needs to be changed.
> > >
> > > For those interested, all this stuff is in jump.c and vidout.c.  The
> > jump.c
> > > opens a2.printlog if someone activates slot 1.  The vidout.c is
obviously
> > > for video output and opens a2.log if running under Linux.  Both look
> > simple
> > > enough and I think they could be easily modified.  The only other
thing I
> > > might need is a dump of the Echo ROM, which I think is in the c400
range
> > > for slot 4 from within the monitor.  I could very well have no idea
what
> > > I'm talking about, but I would like to try more experiments.  My
initial
> > > attempt did work reasonably well, but not quite good enough.
> > >
> > > If anyone else wants to try this, do the following from DOS.  First,
> > unload
> > > the screen reader and the synth drivers.  I use Vocal-Eyes so I do "ve
/u"
> > > and I use the DEC-Talk Express so I do "dtexp /u."  Then, assuming you
are
> > > in com1, do the following:
> > >
> > > a2 >com1 disk.dsk
> > >
> > > Replace disk.dsk with a bootable disk.  Speech should come directly
out
> > the
> > > synthesizer.  Try cataloging to make sure.  If something bombs, hit
> > Control
> > > C, "q" and enter.  If nothing happens, repeat.  Exit the DOS window or
> > > somehow reload your screen reader.  This isn't perfect since you don't
get
> > > review mode at all and it doesn't always speak right away as it
should,
> > but
> > > it is a good start.  I believe that it can be done, maybe easier than
I
> > > thought.  Criticisms are welcome.
> > >
> > > Oh, I made a mistake about A2.  It is not licensed under the GPL.
Make
> > > sure to read the comments in the source before changing anything.  It
> > > allows free copying and distribution, but it doesn't comply with the
GPL
> > so
> > > may not be considered "free" by some people.  I'm not personally
bothered
> > > by it, but others might be.
> > >
> > > At 08:21 PM 7/27/2005 -0400, you wrote:
> > > >Actually my Doubletalk can be freely switched between Echo and
Doubletalk
> > > >mode.  To use Doubletalk, in Basic you just type pr#X where X is the
slot
> > > >where the card is installed.  Then the card emulates a printer in
that
> > slot,
> > > >so anything sent to it will be spoken with the Doubletalk voice.  To
use
> > the
> > > >Echo emulation, which isn't perfect but does get the job done, you
must
> > load
> > > >the Textalker software as if you had a real Echo installed.
> > > >Jayson.
> > >
> > > _______________________________________________
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> >
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