[hylafax-devel] My RTN patch and many other changes/enhancements, thOR

[Dr. Harald Pollack <Harald.Pollack@Datanews.at>]

On Fri, 14 Apr 2000 17:17:54 -0600 (MDT), Steve Williams wrote:

Hello Steve!

>First, I can see that this is almost a "religious" topic, but I am not an
>"evangalist".

Yes, this is problematic, it should be more a pragmatic topic.

>Question Dmitry/Harald, , do you have any experience on what happens when
>the NVRAM "wears out"?

Thw NVRAM does not die from one to the other moment. It looses live very slowly and malicious.

First one bit is not rewritten, than another, and so on. A lot of modem problems raises, because 
the faults are not obvious and not visible at the first sight.

The specifications of a certain chip is not the only fact for how often the chip can be 
reprogrammed. Programming algorithm in firmware also influences the behaviour of stored bits. 
Programming of EEPROM might be often a very time consuming act, so manufactures tend to makes 
things faster and so NVRAM is not so often reprogramable as specification will tell us.

There are a lot use USED modems on the second hand market, which seems to work well, but in some 
circumstances they will fail because one or more bits are inprogrammable.

>We also have a few other data communication applications that use our
>modem pool to communicate to hospital labs, etc ( and unfortunately, one
>of those is the ones that does the at&w with bogus codes...and we don't
>have the source code for it and I don't want to a binary patch too
>much..).

But a patch is often a practicable solution to remove those &W from initialisation (replace it by 
E0 or similar :-)

>I agree that ATZ is an adequate ( my words, not yours ) to resetting the
>modem if there is ONLY ONE APPLICATION accessing the modem.  ( sorry to
>shout!!).

I have a strategy (which I - maybe - proclaim sometimes like an evangelist :-)

In the moment you open the box with your new modem, connect it to a simple terminal emulation and 
store factory defaults in NVRAM (normaly AT&F ... count till 20 ... AT&W) and than adjust some 
FEW parameters for localy necesseties (like ATXn, blind dialing, and so on) and store them again 
by AT&W. From this moment on, the modem is initialized for you network environment. It should be 
quite equal if you do a data or fax or voice call with this modem, in ANY case it will work. 

And after this, only A FEW addtitional setup is needed by some special software (like hard/soft 
handshake or bitrate, commandecho etc.) and this can be done in context with dialing command (in 
case of outgoing calls) or answering command (in case of incoming call).

But I know, this lifts a lot of mystery of the use of a modem and is not always the indention of 
some people :-)

I have a lot of modems of different brands in (alternate) use, and I can use ALL of them with any 
software WITHOUT a 'modem specific' setup! I have THE SAME initialisation (ATZ :-) for each 
modem. And I do all the things which are imaginable with my modems.

>In a mixed data/fax/human fingers environment, where the status of the
>modem is completely unknown,

After ATZ it IS known :-)

>ATZ just doesn't cut it.  I don't really see
>any command that does the job adequately.  As far as I am concerned, in a
>mixed environment, where you can't depend on the state of the modem, the
>only way is to set the modem to factory defaults and then program the
>whole thing from scratch.... AT&F is the only SURE BET for resetting the
>modem!!

Yes, but keep in mind, that not so long ago, people were SURE, that earth is a disk (and you may 
fall down if you reach the border of it :-)

All I want to say is, that everybody can learn new things ... (including me and you :-)

>Enough about ATZ...it's not that important in my book, but I just wanted
>to clarify my personal experiences.

Maybe your experiences were influenced by dubious environment ? :-)


Mit herzlichen Gruessen / Yours sincerely

Dr. Harald Pollack

Harald.Pollack@DATAnews.at



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