Text-To-Speech on Phones: Nuance Talks

[Doug Sutherland]

Kirk,

This may not jive with synth manufacturers, but I am keen
on standard USB devices that "just work" because they
use the standard drivers. In the case of a USB serial port,
the CDC (Communications Device Class) already provides
a COM port class driver for the serial device (this is true
on both linux and windows per the USB CDC spec):

http://www.usb.org/developers/devclass_docs/usbcdc11.pdf
Sorry the spec is only available in pdf

I have firmware that implements the USB CDC
http://www.atmel.com/dyn/resources/prod_documents/doc6269.pdf
Sorry again this is only available in pdf

The CDC can be very complicated depending on the device,
but it can also be very simple in the form of what appears as
a virtual COM port to the system. This is what I am working
towards, so the existing USB class driver in the kernel will
already support the device. The source for the USB serial
device is in

/usr/src/linux/drivers/usb/serial/usbserial.c

Assuming that a virtual COM port is available, the speech
synth connecting through this microcontroller with USB
device hardware, and implementing USB CDC ACM in
firmware, should be very similar to existing RS232 serial
doubletalk driver.  In fact,  the microcontroller simply
functions as a USB device, with the firmware correctly
implementing CDC, all the firmware does is pass the data
out a TTL level UART to the speech hardware.

I will take a look at the existing speakup doubletalk code
soon and see if I can find a way to make this work ...

  -- Doug


Kirk Reiser wrote:
I need to write speakup device drivers to handle the usb synths
such as the TrippleTalk  and DECTalk usb synths.  I have not started
working on that yet