[comp.dcom.modems] Defeating call waiting on incoming calls - SUMMARY

nelson@sgi.com (Nelson Bolyard) (08/03/90)

In <11087@odin.corp.sgi.com> I wrote:
>It is possible to defeat call waiting for the duration of an incoming call.
>The following method works well, and was explained to me by a representative
>of Pacific Bell.  To use this method, one must have the 3-way calling
>feature in addition to call waiting.  
>	1. Answer the phone.  Tell caller to wait for a few seconds.
>
>	2. Flash the switch-hook and get a second dial-tone (this is the
>	   step that doesn't work unless you have 3 way calling).
>
>	3. Dial *70 (or whatever the call waiting defeat sequence is in
>	   your area) and wait for the confirmation tone (3 quick beeps of
>	   dial-tone sound).
>

After step 3, you are immediately reconnected with the incoming call, and
you will receive no call-waiting interruptions for the remainder of the
call.  Flashing again after step 3, which I originally suggested, is wrong.

I then explained that I wanted my modem to do this for incoming calls, but
had been unable to get it to do so.  

>If you know of some magic incantation which will enable my modem to
>cooperate and dial during the call,  I'd very much appreciate it!
>
>Please reply via email to an address below, and I'll summarize if anything
>works!

I received two replies which contained very helpful suggestions.  After some
experimentation with those ideas, I am now able to succesfully defeat call
waiting on all incoming calls.  Here are the details for your enjoyment:

	1.  Disable auto-answer S0=0.
	2.  When the modem says "RING" send it the following string:
	     ATX3DT,!,*70,R


According to my T2500 reference manual, this means as follows:
	AT	get modem's attention
	X3	don't wait for dial tone before proceeding to dial.
	D	Dial
	T	using Tones
	,	wait two seconds
	!	flash the switch-hook
	,	wait two seconds
	*70	defeat call waiting
	,	wait two seconds
	R	go into answer mode

This also works with S8 (pause time for comma) set down to 1, but then two
commas are needed after the *70.

I wish to thank the two individuals who contributed to my success.  They are:
>-----------------------------------------------------------------------------
>Toby Nixon, Principal Engineer     Fax:    +1-404-441-1213  Telex: 6502670805
>Hayes Microcomputer Products Inc.  Voice:  +1-404-449-8791  CIS:    70271,404
>Norcross, Georgia, USA             BBS:    +1-404-446-6336  MCI:       TNIXON
>                                   Telemail: T.NIXON/HAYES  AT&T:     !tnixon
>UUCP:   ...!uunet!hayes!tnixon     Internet:        hayes!tnixon@uunet.uu.net
>MHS:    C=US / AD=ATTMAIL / PN=TOBY_L_NIXON / DD=TNIXON
>-----------------------------------------------------------------------------
who suggested using comma instead of W, setting S8 down, and doing the *70
BEFORE the modem got the carriers established; and:

>Matthias Urlichs -- urlichs@smurf.sub.org -- urlichs@smurf.ira.uka.de
>Humboldtstrasse 7 - 7500 Karlsruhe 1 - FRG -- +49+721+621127(Voice)/621227(PEP)

who suggested using R to go into answer mode instead of ;A .

I hope this information is useful to many of you who must use dial-back
modems, as I must.

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Nelson Bolyard                MTS Secure IRIX            Silicon Graphics, Inc.
nelson@sgi.COM      {decwrl,sun}!sgi!whizzer!nelson      415-335-1919
Disclaimer: Views expressed herein do not represent the views of my employer.
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