Very Computer

I think you have a small problem.  The RS-232 serial interface on yor Linux
box is doing Async communication.  The DSU want Sync communication (hence
the Transmit and Receive clocks).

I don't know much more than this.  Good luck.

Mike Rayborn

says...

Quote:> X-Article-Creation-Date: Fri Apr 23 17:15:07 1999 GMT
> X-Http-User-Agent: Mozilla/3.04 (Win95; I; 16bit)
> X-Http-Proxy: 1.0 x1.dejanews.com:80 (Squid/1.1.22) for client 209.113.193.216

> In short: Can I hook a 56k DSU that seems to have a serial interface to a
> Linux box and use the Linux box as a router to replace my dead Cisco?

Basically, you need to buy a synchronous serial card that is supported by
Linux. You should also take a look at: http://www.etinc.com/

Also, take a look at this Linux Journal article:
http://www.linuxjournal.com/issue50/2928.html

which talks about a router card from this company:
http://www.sangoma.com/

This web page has links to a lot of serial card vendors:
http://www.ntlug.org/~cbbrowne/lincomhard.html

You could also look at www.blackbox.com to see if they have any "dumb"
synchronous serial cards.

--

Give this a looky too.

www.linuxrouter.org

Kevin Kultgen

I found more stuff.

ImageStream sell an all-in-one-box solutions (running Linux):
http://www.imagestream-is.com/

They also resell (and use) the synchronous cards from SDL Communications:
http://www.sdlcomm.com/

The RISCom/N2s is what you're after.

The pricing at ImageStream for this card is $655. ImageStream indicates
Linux support. I didn't surf the SDL Communications site for price or
support.

The price seems high to me... let me know if you find cheaper stuff.

--

On Fri, 23 Apr 1999 17:15:07 GMT,

 brought forth the following words...:

Quote:>In short: Can I hook a 56k DSU that seems to have a serial interface to a
>Linux box and use the Linux box as a router to replace my dead Cisco?

>In longer format:

>I have a Cisco 2501 that died the other day. I need to get something running
>in a hurry. I'd love to replace it with Linux, and show the people in higher
>places in my company how cool Linux is, and how cool I am. <G>

>Anyhow, I need to connect a linux box to an Adtran DSU 5600, which is a 56k
>DSU that seems to have a serial connection. The label above the db25 port on
>it is "EIA-232", which, when I looked it up, is short for Electronics
>Industry Association, or something like that, anyway, it's equivalent to
>RS-232.

>When I look at the pinout for this DSU and compare it to the pinout for an
>external modem, everything is the same except for two pins. Those two pins
>are:

>On the DSU:
>15 Transmit Clock (SCT)
>17 Receive Clock (SCR)

>On modems:
>20 DTR
>22 Ring detect

>Do I need to make a cable that uses SCT/SCR, possibly in replacement of
>DTR/Ring? What kind of software do I need to use?

>When querying the Cisco, it says that it's setup with PPP encapsulation to
>the outside world (thru the DSU), and the serial interface that the DSU is
>connected to has no IP address. I plugged the DSU into the linux box as if it
>were a modem, and ran pppd as if there was a modem connected to that port.
>The DSU lights up a few lights for a few seconds, during which pppd is still
>a running process. Then, after those mayb 5 or 10 seconds go by, the pppd
>process is terminated and the lights on the DSU go off.

>Please, any help would be appreciated, especially if you can tell me how to
>make it all work. I looked thru all the FAQs and HowTos on
>http://www.linux-howto.com and didn't find anything relevant, but if you know
>of a faq or howto that pertains to me, please, feel free to point me at it.

You have a synchronous DSU, it is possible that there is a setting for
async mode, check the manual (if you have it.) Other than that, it's a
hardware hack, and not easy to describe in a paragraph or two.

--
Jim Richardson
        www.eskimo.com/~warlock
All hail Eris
"Linux, where do you want to go tomorrow?"