Hello Everyone,
 
On Wed, 21 Feb 1996 19:04:09 -0500, "James B. Byrne" <[log in to unmask]>
wrote:
|I believe that all modems that respond to the Hayes command set
|will recognize +++ as a switch to local command mode
|instruction, but only after a pre-determined time of inactivity.
|
|--
|James B. Byrne                 mailto:[log in to unmask]
|Harte & Lyne Limited           http://www.harte-lyne.ca
|Hamilton, Ontario              905-561-1241
|
 
The feature of allowing "+++" to cause an exit from data mode to command
mode only when some "guard time" (idle time on both sides of the "+++")
is patented by Hayes.  They license this "technology" to other modem
vendors and have been known to sue vendors who privide this feature
without a license.  The guard time is important because it prevents the
string of three plus signs ("+++") in a datastream from being recognized
as a command to exit data mode.
 
Some vendors have implemented the "+++" sequence to exit data mode WITHOUT
the guard times; either in ignorance of the importance of it, or in order
to avoid the licensing issue with Hayes.  On these modems, any string of
three or more plus signs ("+++"), even in a text message such as this one,
will cause the modem to enter command mode and stop the data flow.
 
Those of you who successfully retrieved this message over a modem probably
have guard times implemented.  Those with inferior modems, are probably
still unenlightened.  Now, aren't you glad you bought a good modem?  :)
--
Jeff Woods <[log in to unmask]> [PGP key available]
Women and cats will do as they please. And men and dogs should relax
and get used to the idea. -- Robert A. Heinlein (1907 -1988)