ATX - enable result code formats and tone detection such as busy and   
             dial tone   
             X0 - most basic, just indicate CONNECT   
             X1 - full message indicating line speed, eg. CONNECT 9600   
      
       ATZ - reset modem to startup condition   
             Z or Z0 - restore to conditions set in &W0   
             Z1 - restore to conditions set in &W1   
      
      AT&C - DCD/RLSD mode   
             &C or &C0 - DCD always indicated on to terminal   
             &C1 - DCD follows modem carrier   
      
       AT&D - function of DTR line   
              see your modem manual   
      
       AT&F - set up factory configuration   
              see your modem manual   
      
       AT&W - store present configuration in modem's non-volatile memory.   
              see your modem manual and the ATZ command above.   
      
       These represent only a fraction of the commands available in any   
       one modem, but beyond this, implementations of the AT command set   
       begin to diverge widely and wildly.   
      
       S-register   
      
       When implementors of modems are too lazy to conjure up a new AT   
       command for a new function, the function is instead left in something   
       called an S-register.  These vary even more widely between   
       manufacturers than do the AT commands, so you are best off to remain   
       away from these if and when you possible can.  Good manufacturers   
       will have most or all of the functions in any S-register replicated   
       in an AT command, with the exception of the first 13 "classical"   
       S-registers:   
      
       S0 = number of rings before modem is permitted to grab the line   
            (0 = no answer, ie. AutoAnswer off)   
       S1 = ring count - read only, cannot be set   
       S2 = escape code character - normally set as "+" to use +++   
       S3 = carriage return, or RETURN or ENTER, character   
       S4 = line feed character   
       S5 = backspace character   
       S6 = wait after going off hook, before dialling   
       S7 = length of maximum wait for carrier after dial   
       S8 = pause for "," in dial string - see details in your modem's   
            ATD command   
       S9 = carrier detect response time   
       S10 = lost carrier to hangup delay   
       S11 = tone duration during tone dialling   
       S12 = escape code guard time   
      
   HSP - (H)ost (S)ignal (P)rocessor - a modem that depends of the CPU of   
   the host system for part or most of the data/signal processing.   
      
   HST - (H)igh (S)peed (T)echnolgy - a family of proprietary high-speed   
   modulation and error-correction protocols developed by US Robotics.   
      
   IRQ - (I)nterrupt (R)e(Q)uest Line - a hard-wired path to a CPU which   
   requests on a prioritized basis that the processor interrupt a task in   
   progress. On DOS systems, Comm Ports 2 and 4 are assigned to IRQ3, and Comm   
   Ports 1 and 3 are assigned to IRQ4. By virtue of Comm2 and 4 having a lower   
   (thus higher priority) IRQ, it is preferable to have a high-speed device   
   such a a modem attached to it when running multi-tasking platforms which   
   run on top of DOS, or when using multiple serial devices (eg. mouse and   
   modem).   
      
   ISDN - [I]ntegrated [S]ervices [D]igital [N]etwork is a set of standards   
   for transmission of simultaneous voice, data and video information over   
   fewer channels than would otherwise be needed, through the use of   
   out-of-band signalling. The most common ISDN system provides one data and   
   two voice circuits over a traditional copper wire pair, but can represent   
   as many as 30 channels. Broadband ISDN extends the ISDN capabilities to   
   services in the Gigabit range.   
      
     BRI- A Basic Rate Interface is two 64K bearer ("B") channels and a   
     single delta ("D") channel.  The B channels are used for voice or   
     data, and the D channel is used for signaling and/or X.25 packet   
     networking.  This is the variety most likely to be found in   
     residential service.   
      
     PRI - Primary Rate Interface. Inside North America and Japan, this   
     consists of 24 channels, usually divided into 23 B channels and 1 D   
     channel, and runs over the same physical interface as T1. Outside of   
     these areas the PRI has 31 user channels, usually divided into 30 B   
     channels and 1 D channel and is based on the E1 interface.  It is   
     typically used for connections such as one between a PBX (private   
     branch exchange, a telephone exchange operated by the customer of a   
     telephone company) and a CO (central office, of the telephone company)   
     or IXC (inter exchange carrier, a long distance telephone company).   
      
   ISP - (I)nternet (S)ervice (P)rovider, an organization that provides   
   access to the internet.   
      
   ITU-T - Formally the International Telecommunications Union - Technical   
   Standardization Sector. it is a consulting arm of the United Nations   
   chartered with the setting of international standards for   
   telecommunications services and equipment. Its members are the national   
   authorities in each country responsible for regulating and providing   
   telecommunication services. It should be noted that though the ITU is   
   chartered with technical tasks, it is a political organization, and   
   therefore subject to all of the trappings thereof.   
      
   KERMIT - Kermit is a protocol designed for transferring files between   
   micro- computers and mainframe computers.  It was developed by Frank DaCruz   
   and Bill Catchings at Columbia University in New York and is widely   
   accepted, especially in the academic world.  Kermit was named after the   
   fuzzy, green talking frog of Jim Henson's "The Muppet Show".   
      
   There are both public domain, and copyrighted Kermit programs that not only   
   include the protocol but are complete programs in themselves offering the   
   communication functions needed for the particular machine on which they are   
   running.   
      
   LAP-M - (L)ink (A)ccess (P)rocedure for (M)odems - an error control   
   protocol incorporated into ITU-T recommendation V.42.   
      
   --- MPost/2 v2.0a   
    * Origin: Marsh BBS (c) Dawson Creek BC Canada (1:17/23)