Re: Echo II sound cards

[mjmahon@aol.com (Michael J. Mahon)]

Ben Yates replied:

>mjmahon@aol.com (Michael J. Mahon) wrote in message
>news:<20040329130730.15684.00000286@mb-m04.aol.com>...
>> Ben Yates wrote:

<snip>

>> >I wonder why no one has ever tried to interface a TI speech
>> >synthesizer to any other type of system. I have other systems and if I
>> >had time I'd love to try it.
>> >But still someone would have to write a good text-to-speech system to
>> >go beyond the built-in words.
>> 
>> The Echo _is_ a TI speech synthesizer interfaced to an Apple II,
>> so I'm not sure what you're getting at here.
>
>I mean a "TI speech synthesizer", literally, the box TI made that
>plugs into the side of the 99/4A. There are a lot of those floating
>around, and they can be had for cheap. The interfacing is simple. And
>with this solution, you have the 300 built-in words in the speech
>roms. And can send direct LPC strings.

No doubt because it has a specialized interfact to the 99/4 bus,
and only provides a TI synthesizer chip and a ROM containing
TI 9900 software to interface to TI BASIC and a 300 word vocabulary.

This is not of much value on a disk-equipped Apple II, which could
have a large vocabulary on disk, or an unlimited vocabulary with
text-to-speech software.

Echo II cards are also quite readily available and inexpensive, and
Apple software and large vocabularies are also readily available.

>[snip]
>
>> 
>> I don't recall if _any_ of these text-to-speech algorithms provide an
>> interface to capture the phoneme/allophone/sample/LPC stream that
>> they generate to control the synthesizer/DAC.  That would not be a
>> very difficult hack, but my guess is that very few saw it as particularly
>> useful, since text-to-speech is relatively compact, runs very fast,
>> and has unlimited vocabulary.
>> 
>> Why, exactly, do you want to capture the stream rather than simply
>> regenerate it as needed?
>
>For languages which do not have access to text-to-speech. Say a Basic
>compiler, an assembler, or even UCSD Pascal which supports LPC strings
>but not a text-to-speech generator. I used such a tool to add speech
>to a Poker game for a Basic compiler that supports only LPC strings,
>but not the text-to-speech assembly routines (which are provided as
>object code for Extended Basic only).

BASIC compilers generally make some provision for "attached" machine
language programs, and Pascal provides excellent tools for incorporating
assembly language code.  I would be surprised if there were not a Pascal
"unit" to interface to an Echo card, but if not, it would not be hard to make
for anyone motivated to do so.

It would also be possible to "capture" the LPC streams for desired
utterances, if that were preferred, but this approach would also require
M/L interface code at run time to pump the streams to the chip.

The situation is that speech was never a widely available option on
Apple II's--meaning more than 10% of the systems--so it did not
achieve "critical mass", and did not get the software support that
could have made it more useful.

At one time, TI hoped to have a self-sustaining business in creating
new custom "vocabularies" for its synthesizer chip, and so did not
promulgate software for allowing others to easily generate the LPC
streams.  In retrospect, this was probably a mistake.

-michael

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