Spec for V21 and/Or V22

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Hi all

Im looking for the spec on V21 and/or V22 ccitt modem standards.
I know they are in the blue book but I dont have it.

I found a post from 1991 saying that they were available for FTP from
but Ive had no luck with this. Can anybody help.

Even if you have the blue book and would fax the V21 spec. Just the section
on the communications sequence, frequencies etc.

Many thanks for any help.

FAX 00353 1 8531776 (just in case I get lucky)

Re: Spec for V21 and/Or V22
I read in sci.electronics.design that Denis Gleeson <dgleeson-
snipped-for-privacy@utvinternet.com> wrote (in < snipped-for-privacy@posting.googl
e.com>) about 'Spec for V21 and/Or V22', on Mon, 20 Sep 2004:

Quoted text here. Click to load it

You can download up to three ITU-T standards for free from the web site
in any one year. There are a few which are exempted, though.

http://ecs.itu.ch/cgi-bin/ebookshop /

The site is not very user-friendly; you may find you've bought them
instead! Follow the instructions very carefully.

Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
We've slightly trimmed the long signature. Click to see the full one.
Re: Spec for V21 and/Or V22
By author:     snipped-for-privacy@utvinternet.com (Denis Gleeson)
In newsgroup: comp.arch.embedded
Quoted text here. Click to load it

CCITT V.21 uses:

Originate mark    -  980 Hz
Originate space    - 1180 Hz
Answer mark    - 1650 Hz
Answer space    - 1850 Hz

It's simply FSK of a 300 bps asynchronous (RS-232) data stream; it can
at least in theory be implemented completely as an analog device.

North America sometimes uses Bell 103 instead, which uses 1270/1070
and 2225/2025 for mark/space.

Here is a useful quick reference:



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