From: gerrit@laosinh.stgt.sub.org (Gerrit Heitsch)
Newsgroups: comp.dcom.modems
Subject: Re: BocaModem settings
Date: 10 Oct 92 18:46:37 GMT
Organization: Lao-Sinh project (private UUCP site)

In article <117.6917@okys.infoserv.com>, Rene Madsen writes:

> I have the BocaModem 14400 internal which in general works ok. Only, I'd
> like to be sure of the following:
According to the settings you have posted, Boca uses the command set
suggested by Rockwell. I will answer your questions with the
commands I would use on my supra V.32bis.

> 1.	I want connections initiated WITH V.42 LAPM error correction.
> 	I DON'T want the alternative V.42 MNP-4 error correction.
ATS48=128S36=0

S48=128  Try to establish a LAPM Connection, if it fails, do as
         I told you in S36.

S36=0    Disconnect.

This setting means, if the modem is not able to negotiate a V.42
connection (because the other side does not support it) it will
disconnect.
 
Default settings for S36 is 7 and for S48 is 7.

> 2.	I DON'T want V.42bis or MNP-5 compression,
Why not? V.42bis will not slow down transfer if the data is 
already packed.
Ok, the command for turning of the compression is:

AT%C0

If you want to disable only MNP5 use AT&Q9 instead of AT%C0

> 3.	I want the connection to use V.32bis (14400 bps) whenever 
> 	possible, and retrain the line when necessary.
ATN1%E1 and send the Dial-commands at the highest possible speed
your modem or your terminal can manage. For my supra it is 57600.

> Now this would'nt be a problem if the manual was readable (but as y'all 
> know, the Boca manual leaves much to be desired). 
The manual for my supra is not better, the discriptions of the 
commands are taken from the Rockwell Modem Designer's Guide of November 1991.

> About 2: The manual says: AT%Cn; where n=0 disables, and n=1 enables
> data compression.  The exactly same thing does it say about %Mn.
> Does one of them disable V.42bis and the other MNP-5 or how is this
> to be understood?
With AT%Cn you disable both possible data compressions, AT%Mn disables
only V.42bis, but lets you use MNP5 if you call such a modem.
If you use AT%C0, AT%M is not functional.

> Also the manual says (p 72) ... ATN1 (default) allows communication at any
> speeds supported by both modems ... ATN0 requires that the speed of the 
> connection be ... specified by the value of S37 ... then (p 53) the 
> manual contradicts itself by saying S37 ... This register is effective
> only if an ATN1 command is issued... Now what do I beleive???
S37 is only operational if you use ATN0. If I have problems to connect
to some USR-Modems with 14400, I use ATN0S37=9 to limit the connection
to 9600.

> AT &D3 &C1 &S1 &K3 E0 &Q5 
>    |   |   |   |   |  |  
>    |   |   |   |   |  +--> Select error correction mode
>    |   |   |   |   +--> Disable echo of commands to screen
>    |   |   |   +--> Enable RTS/CTS
>    |   |   +--> DSR active according to CCITT specs
>    |   +--> DCD
>    +--> DTR 
I use a simliar setting, but I use &S0. DSR is normally used to indicate
that the modem is on. 

> Geesh, I wish those guys at Boca could learn to write a readable manual!
I don't think that Boca wrote the manual themselves, they simply took the guide
from Rockwell and wrote it down. So they copied the errors too...

> Disclaimer: I'm aware that my writing above may be difficult to understand.
> It reflects the Boca manual!
I hope you can understand my writing...

Gerrit

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         Gerrit Heitsch  Moenchweg 16  7038 Holzgerlingen  Germany
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