Re: speakup, grml and braille blazer

["Kerry Hoath" <kerry@gotss.net>]

don't confuse a null modem with a modem.
A modem is a device that lets your computer talk over phone lines.

You should not have any rj11s near your bns; only serial cables.

There are 2 layouts most commonly used for serial ports, the pc style (dte) 
and the modem style dce.
The blazer has a pc-style wiring on it but the gender is female.
You need to connect pc to pc so you need a null modem.
This is like in nedworking where you wish to connect pc to pc with no hub or 
switch you need a cross-over cable.

A null modem is a device or cabling wire map that allows 2 computers to talk 
to each other over a serial link.
Assume we have 2 computers with a 9-pin serial connection wishing to talk to 
each other.
The cable in use is a straight through. Pin 2 is transmit and pin 3 is 
receive and 5 is signal ground.
If the pins are wired straight through then the transmit and receive pins 
are wired transmit to transmit and receive to receive.

This will not work as the transmit pin on one computer needs to be wired to 
the receive pin on the other. A null modem or cable does this for us.
Usually it's wired as
2 to 3, 3 to 2, (transmit to receive)
5 straight through (signal ground)
4 to 6, 6 to 4, (cts to rts)

Then cd is tied on one end to dsr and possibly dsr.
----- Original Message ----- 
From: "Cody Hurst" <churst35@verizon.net>
To: "Speakup is a screen review system for Linux." <speakup@braille.uwo.ca>
Sent: Tuesday, May 20, 2008 11:19 AM
Subject: Re: speakup, grml and braille blazer


I'm not quite understanding the logic behind the null modem, but ok.
When I plug the rj11 end of the cable to the pc, how do I tell speakup
to look on teh modem port if linux by default is in compatible with
most modems?

On May 19, 2008, at 5:14 PM, Kerry Hoath wrote:

> put a gender changer on the blazer to change the serial port from
> female to
> male on the blazer.
> plug a 25-pin female to 9-pin mail into the converter.
> plug the null modem from converter to pc.
>
> You could also get a 25-pin null modem cable; gender bend the blazer
> end
> then convert it down to 9-pin on the pc end.
>
> the cable needs to be null modem and you need things of the right
> gender as
> the port on the blazer for serial is female.
> Regards, Kerry.
>
> ----- Original Message -----
> From: "Cody Hurst" <churst35@verizon.net>
> To: "Speakup is a screen review system for Linux." <speakup@braille.uwo.ca
> >
> Sent: Tuesday, May 20, 2008 11:07 AM
> Subject: Re: speakup, grml and braille blazer
>
>
> Well I have a db9 null modem cable, but how would I do this
> configuration? the db9 end will not fit on the blazer and vice versa.
> More insight on this would greatly be appreciated.
> On May 19, 2008, at 5:02 PM, Kerry Hoath wrote:
>
>> the blazer requires a null modem cable to connect it to the computer
>> not a
>> straight through serial cable.
>> Regards, Kerry.
>>
>> ----- Original Message -----
>> From: "Cody Hurst" <churst35@verizon.net>
>> To: "Speakup is a screen review system for Linux." 
>> <speakup@braille.uwo.ca
>>>
>> Sent: Tuesday, May 20, 2008 8:03 AM
>> Subject: speakup, grml and braille blazer
>>
>>
>> Hello all,
>>
>>  I just realized I could whip up an external synth with a db25
>> serial cable, a converter and a db9 serial cable, however when I boot
>> grml I use this boot command
>>
>> grml speakup_synth=bns, ttyS0 and get no speech. On the blazer's
>> speech config menu I set it from parallel to serial. however I tried
>> starting grml with it on serial and parallel and still no speech. I
>> know this can be done but I just don't know how. I'd like to know
>> what
>> I"m doing wrong here. Thanks for any hep.
>>
>> Cody
>> _______________________________________________
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>> Speakup@braille.uwo.ca
>> http://speech.braille.uwo.ca/mailman/listinfo/speakup
>
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