speakup and serial hubs?

[Adam Myrow]

There is always the USB to Serial converter option.  I just got a Keyspan
USA 19H converter.  It connects to a USB port, and has a short cable with a
9-pin male RS-232 connector.  There is support for this contraption in
Linux, and from what I've read, Keyspan has been very supportive  of Linux.
I can successfully use Brltty to talk to a PowerBraille 80 via this device
once I re-built the kernel to support it.  It showed up as /dev/ttyUSB0.  I
have my doubts about it working with Speakup as a hardware synthesizer, but
I'd bet it would work with a Modem, or UPS.  They also make multi-port
versions.


-----Original Message-----
From: speakup-bounces at braille.uwo.ca [mailto:speakup-bounces at braille.uwo.ca]
On Behalf Of Justin Ekis
Sent: Thursday, January 06, 2005 5:27 PM
To: Speakup is a screen review system for Linux.
Subject: Re: speakup and serial hubs?

Hi all:

What  I was hoping for was an external box which could do this trick, but I
see that's not realistic at all. I thought I remembered the computers at
school having a box that connected to the port and gave you four serial
ports. Thinking about it more carefully I now remember it was only a switch
box and only one at a time would work.

Really bad question, guess I'm out of luck. I don't know that I have any
free slots available for a card either and wouldn't feel comfortable
installing one if I did.

This isn't even related to Linux now so respond off list if you like. Is
this something that I could go into a computer shop and have upgraded? Would
I perhaps have to get a new motherboard installed or something drastic like
that and how much would it cost?

Justin
On Thu, Jan 06, 2005 at 02:47:30PM -0800, Chris Gray wrote:
>Hi Justin:
>
>Due to the nature of the RS232-C serial specification, there are 
>complications about having something put together like a serial hubb.
>The serial hardware alone takes a fair amount of electronics, the way 
>way serial ports are implemented through the motherboard doesn't lend 
>itself to a hubb like you see today with USB devices.  It's a creative 
>question though.
>
>Before USB, there were lots of board made that attempted to do what you 
>are suggesting, or variants of that.  Enough serial devices still exist 
>that you might be able to find such a device today.  Typically, these 
>were boards that had 4, or more separate serial ports on them, with a 
>ton of jumpers to modify IRQ and port addresses.  Beware of cards with 
>connectors that are just nullcross-overs for the same port; those won't 
>help you.  You must have separate, discrete ports and 
>connectors/jumpers to them.
>
>whether you can find such a card that's both PCI and affordable is an 
>interesting question. I called a local, relatively large computer store 
>here in San Francisco Central Computers, because all this made me 
>curious and they have fairly decent customer service.
>I'm slightly surprised, but It turns out they have a high speed i/o 
>card with two ports for $19.99 from Vitex, it's even in stock!  If they 
>carry it, I bet you could order something from Comp USA if you've got 
>the patience, or find something localy or online.
>
>Hope this helps.
>
>Chris

_______________________________________________
Speakup mailing list
Speakup at braille.uwo.ca
http://speech.braille.uwo.ca/mailman/listinfo/speakup