Connecting hardware synthesizer to speakup without serial port.

Mike Ray mike at
Sun Apr 19 12:05:57 EDT 2015

No, speakup and the Apollo, or any other hardware speech-synthesiser
will not work with a USB to serial adaptor.

I believe this to be because a genuine serial port (RS232) and speakup
use the hardware hand-shaking pins (RTS and CTS?), to communicate
readiness to send and recieve data.  The USB to serial adaptors will
either not support this hardware hand-shaking or it takes a differently
written program to use it.


On 19/04/2015 16:43, Glenn / Lenny wrote:
> Hi,
> I thought that it will work with a USB to serial adapter, but you may not 
> get the initial computer boot-up messages because the USB to serial driver 
> would not have been loaded yet.
> Glenn
> ----- Original Message ----- 
> From: "Ĺ‚ukasz golonka" <wulfryk1 at>
> To: <speakup at>
> Sent: Sunday, April 19, 2015 6:01 AM
> Subject: Connecting hardware synthesizer to speakup without serial port.
> Hi. I have apollo II synthetiser. I would like  to connect it to
> speakup, but i have computers without physical serial port. Usb to
> serial interfaces don't work with speakup of course. Is it possible to
> connect speakup to apollo. I've heard about possibility to connect
> external synthetiser to speakup using express card to com adapter, but
> my computer doesn't  have  physical express card port, so i must again
> use express card to usb converter.
> Thank you for help.
> Lukasz.
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> Speakup mailing list
> Speakup at
> _______________________________________________
> Speakup mailing list
> Speakup at

Michael A. Ray
Witley, Surrey, South-east UK

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