This manual is provided to you in electronic format.  It is supplied for 
the sole purpose of documenting and supporting Mult-Tech Systems' 
products.  Any translation, modification, or unauthorized copying of 
this manual is strictly prohibited.  The information contained herein is 
protected by U.S. copyright laws and international treaties.

This text only manual is based on the MT2834PCS owners manual, 
P/N 82035801, Rev. B.

1.1     Introduction

Data Communications has been laboring towards providing 
multifunction service over a single phone line since the inception of the 
Integrated Services Digital Network (ISDN).  Now, as the capabilities 
of analog, copper phone lines have been expanded beyond what was 
thought possible a few years back, this multifunctionality is on your 
desktop.

Multifunction means that your Personal Communication System (PCS), 
is capable of supporting more than one type of communication session.  
The patent-pending PCS hardware, the MultiModemPCS (model 
MT2834PCS), is capable of performing like a business or residential 
telephone, a computer fax system, or a modem in any environment.  
You can run your own communication software and issue the 
commands which put the MT2834PCS in telephone, modem, or Digital 
Simultaneous Voice Data (DSVD) mode, and it's compatible with any 
CCITT V.17 Group 3 fax software based on the de facto EIA TR-29 
Class 2 command set.

The patent-pending software portion of the PCS is MultiExpressPCS, 
a Windows  3.1 desktop communication package specially designed 
for the MT2834PCS modem.  With MultiExpressPCS running on your 
PC, you can fax from any Windows application, record telephone 
conversations, edit voice files, compose multimedia messages (i.e., text, 
graphics, and voice notes all in one document), and use such telephone 
features as speed dialing, mute, hold, call forwarding, call transferring 
and three-way (conference) calling.  The features of MultiExpressPCS 
are recounted in more depth by the MultiExpressPCS Software Manual. 
The MT2834PCS's Digital Simultaneous Voice Data  mode with 
TalkAnytimeTM, lets you speak with the person at the other end while 
maintaining a PCS-to-PCS datacomm link.  Since the TalkAnytime 
feature is strictly a hardware feature, you can use communications 
software without reprogramming, changing setup strings, or 
reconfiguring the modem.  TalkAnytime activates Digital Simultaneous 
Voice Data  communications anytime the handset is picked up, thus 
activating the "modem" and "telephone" circuits and supporting dual 
communications over a single phone line.  

This manual will help you get the MT2834PCS installed on your 
system, and it will serve as a reference for the modem's operation (i.e., 
"AT" commands, S-Registers, Option Switch Settings, etc.).  

1.2     How To Use This Manual

This manual is divided into several chapters. There are also appendices 
at the end of the manual which reiterate information  presented in the 
main text, in a condensed form.  These can be used as quick-reference 
sections.  The information contained in each chapter and appendix is as 
follows:

Chapter 1 - Introduction and Description
Chapter 1 begins with a short introduction followed by a guide (which 
you are now reading) to the use of the manual. There is a discussion 
about what components you can expect to be in the MT2834PCS 
package followed by a more detailed description of the modem.

Chapter 2 - Installation and Connection
Chapter 2 covers the procedure for connecting the MT2834PCS to your 
computer and to the phone line.  It also details what you will need to 
know about installing your MT2834PCS modem to the point of 
operation with illustrations on the MT2834PCS's back panel 
connections and PC Board controls. This chapter also covers the 
MT2834PCS's DIP-Switch default and optional settings, telephone 
connections when operating in dial-up or lease line modes, basics on 
Dialing/On-Line/Answering modes, and definition on the 
MT2834PCS's LED indicators.

Chapter 3 - Using the MT2834PCS                         
	(Digital Simultaneous Voice Data Mode)
Chapter 3 discusses modes of operation, the means by which  a Digital 
Simultaneous Voice Data session (Voice-Over-Data) is established and 
the nature of the MT2834PCS' Talk Anytime feature.  This chapter also 
describes some of the most common user-configurable AT-Style Digital 
Simultaneous Voice Data Commands.

Chapter 4 - "AT" Commands and S-Registers
Chapter 4 provides basic steps for originating and answering calls and a 
summary of commands which enable the user to establish, read, and 
modify parameters in addition to dialing. This chapter is focused more 
on the traditional "data" mode aspect of the MT2834PCS capabilities 
with the use of "AT" commands and S-Registers.

Chapter 5 - Testing Your Modem
Chapter 5 covers the modem's built-in test features. These are: Power-
on Self Test, Local Analog Loopback Test, and Remote Digital 
Loopback Test.  We have included a description of each test and how to 
use each testing feature. 

Appendices

Appendix A - FCC, Canadian and BABT Regulations             
Appendix B - Technical Specifications                
Appendix C - Multi-Tech Supervisory Protocol      
Appendix D - Tone Dial Frequencies   
			

1.2.1   Typographical Conventions

Within this manual, and many others provided by Multi-Tech Systems, 
there are a few typographical conventions used to minimize confusion.  
One convention is the non-overstricken "0" (number zero).  Please note 
that our upper case "O" is quite similar.

The "Return" or "Enter" key is labeled in various ways, depending on 
the model keyboard and on your system.  We refer to this key as <CR>, 
which means for you to press the "Return" or "Enter" key on your 
keyboard.

The "Control" key (abbreviated "Ctrl" on many keyboards) may also be 
referenced in this manual.  This key, and any others to which we may 
refer, are set off by angle brackets -- like so: <Ctrl>.  If the key is used 
in combination with another key, we use the Windows convention of 
the key, a plus sign, and the next key -- like so: <Alt>+X.  In this case, 
you should press and hold the first key while you strike the second.  If 
more than two keys are called for in a sequence, hold down each key 
and then strike the last one.  For example, if we instruct you to reset 
your computer by pressing <Ctrl>+<Alt>+<Del>, you should press and 
hold the <Ctrl> and <Alt> keys, then strike the <Del> key.

Finally, there are two ways in which we set off text.  We use bolditalic 
formatting to set off the commands as they are described.  If you see 
text that is bold, you should type exactly what is shown, and then press 
any keys listed.  

1.3     What is in Your Personal Communication System?

Your Personal Communication System has several components.  Make 
sure you received them all before you install the modem or its software.  
Your package should include:

*       The MT2834PCS modem

*       An RJ11 telephone cord or BS6312 Plug (BABT)

*       An AC Power transformer

*       MT2834PCS Owner's Manual (this manual)

*       One Intelligent Serial Interface Card (ISI) model ISI551 
	(bundled with model MT2834PCS/ISI only)

*       ISI551 Owner's Manual

If one or more of these is missing, please contact Multi-Tech Systems 
or your dealer/distributor.  

1.4     Description

Your MT2834PCS performs as a telephone, fax machine, or traditional 
modem.  These modes of operation are provided by the modem's 
electronics and can be controlled by any software package from which 
the appropriate commands can be issued.  Multi-Tech's 
MultiExpressPCS software package provides programs which control 
all these functions.  With MultiExpressPCS running on your computer 
(under Microsoftr Windows), your MT2834PCS can also be used as an 
answering machine (i.e., voice messaging service), a voice editor for 
digitized voice files, or as a multimedia message composer.  
MultiExpressPCS also provides a database utility for storing 
information useful in contacting people or organizations with fax, 
multimedia mail or voice message transmittals.  For more information 
on the MultiExpressPCS communication software, refer to the 
MultiExpressPCS Software Manual.  

Your MT2834PCS modem is designed according to the International 
Telecommunication UnionTelecommunications Standards Sector (ITU-
T) V.34 standard (formerly CCITT) for data signalling rates as high as 
28.8/26.4K bps full-duplex mode. Connections can be made on Public 
Switched Telephone Networks (PSTNs) and/or point-to-point 2-wire 
telephone type circuits.

V.34 is an extension of the V.32/V.32bis/V32terbo standards.  V.34 
supports and is compatible with all V.32/V.32bis/V32terbo features 
including EIA extended Automode, adaptive line probing, automatic 
symbol rate and carrier frequency during start-up, and retrain and rate 
renegotiation (in 2400 bps increments).  For fax transmissions, the 
MT2834PCS -- together with the MultiExpressPCS "Fax Manager" 
handles faxes according to the CCITT V.17 standard at 14,400 bps 
when linked with another fax modem  or fax machine capable of V.17 
performance.  It complies with the CCITT's Group 3 Designation at 
9600, or Group 2 (4800 bps) depending on the other fax system 
involved.  The MT2834PCS is also downward compatible with 
modems at speeds as low as 300 bps.  This enables the modem to 
send/receive text, graphics, and images with virtually any fax machine 
in the world.  

With CCITT V.42 error correction and V.42bis data compression, data 
sent will be 100% error free. V.42 error correction incorporates both 
MNPr Classes 3 and 4 and LAP-M. Data compression can be V.42bis 
for 4-to-1 throughput improvement or MNP Class 5 for 2-to-1 
throughput.

The  MT2834PCS offers interactive automatic dialing capability, as 
well as Command Mode option configuration. Up to ten command 
line/telephone numbers, of up to 60 digits each, can be stored in the 
modem's nonvolatile memory. The modem uses pulse and/or tone 
dialing methods, and has the ability to recognize dial tones and busy 
signals for reliable call-progress detection; and the  MT2834PCS has 
the capability to detect AT&T "call card" tones for the purpose of  
accessing the user's calling card before an on-line connection is made. 
The  MT2834PCS is FCC-Registered for connection to the telephone 
networks. No Data Access Arrangements (DAA's) are required.

Callback Security provides MT2834PCS users with a means of 
protecting their networks from unauthorized users.  By use of the 
modem's automatic login routines and phone number/password 
directory, host sites can, after receiving a call, "callback to" a remote 
site at a predetermined number.  This feature can also be used to reduce 
phone line costs for users through host site call origination.
Remote Configuration gives users network management capability.  

Users can configure modems at remote sites from local modems, 
without having to visit the sites or rely on users to follow instructions.
The modem link between two MT2834PCSs becomes a point-to-point 
packet network during Digital Simultaneous Voice Data mode (voice-
over-data).  This transmission between traditional modem 
communications (where data is transferred) to packet mode (where 
packets of data, digitized voice, or commands are transferred in the 
same stream) is done automatically when the attached telephone device 
handset is placed off-hook (Talk Anytime feature).  The MT2834PCS 
uses a patent-pending Multi-Tech Supervisory ProtocolTM (MSP) to 
discern data streams, voice streams, and commands while on-line with 
another MT2834PCS; and thus uses the same analog line to do so.

The MT2834PCS contains all the circuitry necessary for Digital 
Simultaneous Voice Data operation.  Therefore, Talk Anytime engages 
voice-over-data mode when the MT2834PCSs are connected to 
terminals, any type of processor running "AT-compatible" datacomm 
software, or other async devices which have standard RS232 serial 
ports for the modem connection.  The only limitation is that there must 
be a MT2834PCS on each end of the phone-line for voice-over-data 
mode to be activated.

2.1     Introduction

The installation of the MT2834PCS consists of making the physical 
connections necessary to render the modem functional with your 
computer.  This includes making the proper serial, phone line, and 
power connections.  The installation instructions are followed by a brief 
section on issuing AT commands to the modem to manually dial or 
disconnect from another computer.  

2.2     Installation

The following list is an overview of the steps to installing your 
MT2834PCS:

1.      Connect the modem to your computer using an available serial 
	port and a straight-through RS232C cable (or V.24 equivalent). 
	
Note:   Cables connected to the computer must be shielded to reduce 
	interference.

2.      Connect the modem to the PSTN/Leased line using the RJ-11 
	jack labeled "LINE" (see Figure 2-1).

3.      Connect the modem to AC power through the AC power 
	adapter supplied with the modem (see Section 2.2.1).                    

4.      Connect the telephone accessory to the appropriate RJ-11 jack 
	on the MT2834PCS's back panel (see Figure 2-1).  WARNING: Failure 
	to make the appropriate connection (e.g., using the RJ11 jack intended 
	for "LINE" connection, and plugging it into the MT2834PCS's 
	"PHONE" connection), may produce a harmful effect on the operation 
	of your MT2834PCS.

5.      Turn on power by flipping the "ON/OFF" switch at the left 
	rear of the MT2834PCS to the "ON" position (up).

6.      Verify remote modem's current configuration settings with your 
	MT2834PCS in terms of data compression, error correction, 
	transmission rate, etc. (per Chapter 4, ATL5 and ATL7 Commands); or 
	Configuration setting establishing a Digital Simultaneous Voice Data 
	link (per Section 3.4 and Appendix C).

7.      Attach MT2834PCS to dial-up phone lines or leased lines (per 
	Section 2.2.4) and verify DIP-Switch #10 and #5 settings.
	Verify leased line transmit level (DIP-Switch #3) setting 
	(per Section 2.2.4).

8.      Verify self-test results (Chapter 5).

2.2.1   Applying Power

Power is supplied through an AC power transformer terminated with  a 
standard two-prong plug.  The transformer supplies low voltage AC to 
the modem and to the attached telephone device. The transformer plugs 
into any conventional 115 volt AC, 60 Hz, two-prong power outlet, and 
should be the only power source used with the MT2834PCS.  Use of 
any other transformer could cause damage to this device.  

Connect the modem's AC power transformer to a live AC outlet, and 
connect  the end of the power cord to the POWER connector on the 
back of the modem.

Once all connections have been made, you can apply power to the 
MT2834PCS by flipping the power switch (at the left rear when the 
modem is facing you) to the "ON" position (up). 

As soon as you connect power to the modem, it performs a diagnostic 
self-test, indicated by the speed indicators flashing in sequence for 
approximately four seconds, then the 28.8 indicator should light.  The 
TR indicator should also light at the same time for most installations.  
The SD, RD, CD, and OH indicators should remain off at this time. If 
this does not  happen, check that the transformer is solidly connected 
and that the AC outlet  is live.  Refer to Chapter 5 for more information 
on modem testing.

2.2.2   PC Board Controls

The MT2834PCS is designed on a single printed circuit (PC) board.  
This board contains one block of 16-position DIP-Switches (numbered 
1-16). These Switches are accessible through a cut-out on the side of 
the modem.  Located on the front of the modem is a Voice/Data 
"toggle" switch with Originate/Answer capabilities. This switch enables 
the modem to automatically dial a phone number stored in the N1 
location of memory whenever this switch is toggled.  If you are 
"Manually" dialing with an attached telephone device (and not with 
your keyboard), your modem originates when toggled in that position; 
and if you are "Manually" answering (modem is not configured to 
automatically answer via S-Register S0 setup), the 
MT2834PCS answers an incoming call when toggled in that position.

There are also two RJ11 style modular phone jacks, one for PSTN or 
leased line connection, and the second for connection of your telephone 
device for Digital Simultaneous Voice Data application and a knob for 
adjusting speaker volume.  

It is unlikely you will need to access the interior of the modem, but if 
you do, you must remove the modem's PC board from the modem's 
chassis.  To remove the PC board, remove the retaining screw (on the 
bottom of the modem near the RS232 connector), and slide the PC 
board out of the modem chassis.

The sixteen DIP-Switches control various modem options or set default 
values for Command mode operation.  There is a difference in how 
several of the switches operate depending on whether you are in 
synchronous or asynchronous mode.  Refer to the switch label on the 
bottom of the MT2834PCS for an exact list of the switch functions in 
asynchronous and synchronous operation.

2.2.3    DIP-Switch Settings                                    
	
The MT2834PCS typically is used to dial up a remote installation 
where the call is automatically answered.  The factory default DIP-
Switch settings are based on this assumption. The following is a brief 
description and summary of the MT2834PCS's DIP-Switch options:
Switch  Function                        Position        Effect
#1      DTR Forced/DTR from Interface*  UP*             DTR forced from      
					DOWN            computer/terminal

#2      Flow Control &E4* (Async/       UP*             Hardware flow                              
	Dial-Up/Leased Line)            DOWN            control enabled

#2      SDLC*/BSC (Sync)                UP*             SDLC enabled
					DOWN

#3      Result Codes Enabled* (Async    UP              Modem responses 
	Dial-up)                        DOWN*           are enabled
							(echoed)

#3      DbM Transmit 0dB*/-10dB         UP              Lease Line                   
	(Async/Sync/Lease-Line)         DOWN*  transmits at 0dB
(Note that this switch in this mode is not applicable to the MT2834PCSK)   
						
#4      AS/400 Mode Disabled* (Sync     UP*             AS/400 Mode                            
	Dial-Up/Leased line)            DOWN            Disabled
   
#5      Auto-Answer Enabled* (Async     UP*             Auto-Answer     
	Sync/Dial-Up)                   DOWN            in dial-up mode
	
#5      Answer*/Originate               UP*             Originate call in      
	(Async/Sync/Leased Line)        DOWN            Lease Line mode

#6      Max-Throughput Enabled*         UP*             Modem set-up to      
	(Async/Dial-Up/Leased)          DOWN            operate at highest 
							efficiency level
	
#6      Slave Clock Disabled*           UP*             Clock controlled                      (Sync/Dial-Up/Leased)   DOWN  
							by remote device

#7      RTS/Normal/Forced*              UP              Request To Send          
	(Sync/Async/Dial/Leased)        DOWN*           Forced On
	
#8      Command Mode Enabled*           UP              Command Mode     
	(Sync/AsyncDial/Leased)         DOWN*           Enabled 
	
#9      Local/Remote LoopBack*          UP              Remote 
	(Async/Sync/Dial/Leased)        DOWN*           LoopBack Enabled
	
#10     Dial-Up*/Leased-Line            UP*             Dial-Up Enabled
					DOWN            
	
#11     "AT"/Multi-Tech Result Codes*   UP              Multi-Tech 
	(Asynchronous)                  DOWN*           Result Codes            
							Enabled
	
#11     Internal*/External Clocking     UP              Selects Transmit   
	(Synchronous)                   DOWN*           Clock Source
	
#12     Sync/Async Mode*                UP              Asynchronous 
					DOWN*           Mode Enabled

*Factory Default Setting

DIP Switches #13-16
    
Switch          Condition       Effect
#13/#14         UP/UP*          28.8 K bps Operation (Default)
		
#13/#14         DOWN/UP         19.2 K bps Operation
		
#13/#14         UP/DOWN         14.4 K bps Operation
		
#13/#14         DOWN/DOWN       9600 bps Operation
		
#15             UP*             CD/DSR from Interface
#15             DOWN            CD/DSR Forced On
#16             UP              Used in combination     
#16             DOWN            with DIP-Switch #9/Loopback 
				Tests (see Chapter 5 for 
				Loopback Tests)

2.2.4   Telephone Connections (Dial-Up/Leased Lines)

The MT2834PCS modem is designed for communications over Public 
Switched Telephone Networks (PSTNs) lines in dial-up or leased-line 
mode.  Connection to the PSTN can made via RJ11-type jacks such as 
the RJ11C or RJ11W (dial-up/leased line mode use the same RJ11 
connection).  When in dial-up mode, the MT2834PCS is designed to 
transmit at a permissive level of -10 dBm.  In leased-line mode, the 
MT2834PCS's transmission level is 0 dBm, with an optional -10 dBm 
setting (not applicable for the MT2834PCSK).

To connect the MT2834PCS modem to the phone line, plug one end of 
the RJ11 cable provided with the modem into the connector labeled 
"LINE", and the other end into an RJ11-style modular wall jack 
provided by the phone company. Make sure that DIP-Switch #10 is in 
the UP position (default).

To connect the modem to leased lines, first determine the type of line 
termination provided by the phone company.  Most phone companies 
provide a terminal block with a pair of screws.  Some provide a 
conventional RJ11 type of connector.  If the RJ11 connector is used, 
you can use the same cable that you use for dial-up connection (for 
BABT connections, a BS6312 Plug is used).  If the screw terminal type 
connector is used, you may need to order the appropriate  cable 
(#CA167) from Multi-Tech Systems . 

Make two DIP-Switch setting changes on the modem's PC board to 
enable leased line mode.  The first involves placing DIP-Switch #10 in 
the DOWN position (changes the modem from dial-up to leased line 
operation). The second DIP-Switch change requires that one of the two 
modems on the leased line circuit is set to "originate", and the other is 
set to "answer".   To do this, change the setting of DIP-Switch #5.  
When you changed the DIP-Switch #10 setting, you also changed the 
function of DIP-Switch #5.  Now the UP position selects answer mode 
while the DOWN position selects originate mode.   Place DIP-Switch 
#5 in the UP position on one of the two modems, and on the other 
modem, place Switch #5 DOWN. It  doesn't matter which is which, just 
so you have local and remote modems in opposite modes. 

To connect the MT2834PCS modem to utilize telephone accessory, 
plug one end of the RJ11 cable provided with the modem into the 
connector labeled "PHONE", and the other end into the telephone's 
RJ11-style connector.

2.3    Dialing/On-Line/Answering

There are several basic steps for "originating" and "answering" in data 
communication mode:
	
	1.      Load communication software
	2.      Dial
	3.      Establish On-Line connection
	4.      Terminate Call  

A simple way to dial is from the keyboard of your computer or 
terminal.  You enter a command on the keyboard to tell the 
MT2834PCS to dial.

If you use one of the more sophisticated communications software 
packages (e.g., MultiExpress), the software tells you to enter phone 
numbers and other information.  If this is the case, the software, and not 
you, gives the dialing commands to the modem. All of the  commands, 
S-Registers and intelligent features of the MT2834PCS are taken care 
of by the software.

If you are giving commands directly to your modem (and not through 
your software), each command must begin with AT (ATtention 
Characters). AT characters may be entered in upper or lower case.
Entering AT automatically sets the modem's speed to match the speed 
of the computer or terminal, and also sets the modem's parity. If you are 
using a terminal, you can issue commands directly, but computers must 
be placed in terminal mode before the modem recognizes commands.  
To operate a computer in terminal mode, you must run a datacomm 
package like MultiExpress, or MultiExpress for Windows, depending 
on the type of datacomm call you want to place and whether you are 
calling under DOS or Windows environment.  Refer to your software's 
documentation to load and run the datacomm software.

Once your computer is in terminal mode, the procedure for establishing 
a call (using AT commands) is the same as the procedure for users of 
terminals.  

AT characters alert the modem that a command follows.  The AT 
Command can also be used to clear the command buffer, by simply 
typing AT and hitting RETURN.

The letter D in a command causes the modem to dial the numbers 
immediately following it (e.g., ATD6127853500--tone dialing method 
only). 

The MT2834PCS responds with "CONNECT" on your video display 
after the number is dialed and a connection signal is detected (since the 
MT2834PCS defaults to V.34/V.42/V.42bis, the actual response is 
"CONNECT 28800 LAPM COMPRESSED"), if the MT2834PCS 
"connects" with a similar modem (see section 4.3 Result Codes).  The 
modem is now in "On-Line" mode, and is ready to communicate with a 
host  site.  

If no connection signal is detected within 45 seconds (this time period 
can be adjusted by S-Register S7--see section 4.2 on S-Registers), the 
MT2834PCS goes On Hook/hangs up and returns to Command mode.  

At this point, your video displays "NO CARRIER".
Enter ATH<CR> to Hang Up On-Line (bring modem on-hook), and 
terminate the modem's On-Line mode. At this point, your video displays 
"OK". 

In addition to the call originating capabilities, the MT2834PCS  can 
also automatically answer incoming calls.  You need not be present.  
You can, however, control the situation by configuring the modem to 
either answer or not to answer, or to answer after a specified number of 
rings.  This is done by setting the value of S-Register S0 (modem 
defaults to automatically answer an incoming call after one ring). 

2.4    Modem LED Indicators

The MT2834PCS has fourteen diagnostic LED indicators.  They are:

1)      Transmit (Send) Data (SD).  This LED blinks when data is being 
	transmitted, on for a space, off for a mark.  The state of this LED 
	matches the TD circuit on Pin 2 of the RS232C/V.24 interface.

2)      Receive Data (RD). This LED blinks when data is being received, 
	on for a space, off for a mark.  The state of this LED matches that of the 
	RD circuit on Pin 3 of the RS232C/V.24 interface.

3)      Carrier Detect (CD).  This LED is lit when a valid carrier tone has 
	been detected.

4)      28,800 bps (28.8).  This LED is lit when the modem is connected at 
	28,800 bps. Note: if the modem falls back to 26.4K bps while in V.34 
	mode, both the 28.8 and 24.0 LEDs light.

5)      24,000 bps (24.0).  This LED is lit when the modem is connected at 
	24,000 bps. Note: if the modem falls back to 21.6K bps while in V.34 
	mode, both the 24.0 and 19.2 LEDs light.   

6)      19,200 bps (19.2).  This LED is lit when the modem is connected at 
	19,200 bps.  

7)      14,400 bps (14.4).  This LED is lit when the modem is connected at 
	14,400 bps.  Note: if the modem falls back to 12,000 bps while in 
	V.32bis mode, both the 14.4 and 96 LEDs light.

8)      9600 bps (96).  This LED is lit when  the modem is connected at 
	9600 bps.

9)      2400 bps (24).  This LED is lit when the modem is connected at 
	2400 bps.

10)     Off Hook (OH).  This LED is lit when the phone line is "off 
	hook".  This occurs when the modem is dialing, on-line, or answering a 
	call.  This LED also flashes when the modem is pulse dialing in 
	Command mode.

11)     Terminal Ready (TR).  When the TR LED is lit, the modem is 
	permitted to answer an incoming call.  When it goes off, a connected 
	modem will disconnect.  The state of the TR LED matches that of the 
	DTR circuit on Pin 20 of the RS232C/V.24 interface.

12)     Error Correction (EC).  This LED is lit when the modem is set for 
	V.42 error correction, and flashes on and off when data compression is 
	activated.

13)     FAX (FX).  This LED is lit when the modem is connected in FAX 
	mode.

14)     ERROR (ERR).  When this LED is lit, either the leased line is 
	down, or else the self-test has failed.

3.1     Digital Simultaneous Voice Data Communications

In addition to a conventional modem's command and on-line modes, the 
MT2834PCS has a "packet mode" in which it can receive packets of 
voice, data, or commands from the PC while it is on-line.  A header in 
each packet uniquely identifies its contents.

In conventional (non-PCS) modem operation, the on-line connection 
between modems must be suspended, by "escaping" to command mode, 
before commands can be issued to the modem.  But your PCS uses our 
patent-pending  Multi-Tech Supervisory Protocol,  (MSP), to discern 
data streams, voice streams, and commands while it's on-line with 
another PCS (e.g., MSP is utilized when the PCS is used for recording 
and playing back voice messages in answering machine mode).  This 
packet mode allows the connected PCSs to transmit voice and data over 
the same analog phone line, at the same time.

3.2     Establishing a Digital Simultaneous Voice                       
	Data Link

Establishing a Digital Simultaneous Voice Data link means that the 
modem and attached telephone device, are each set up using a single 
phone line.  This Digital Simultaneous Voice Data communication is 
made possible by buffering incoming voice and data streams, separately 
packetizing portions of each, and then multiplexing both types of 
packets over the same line.  The multiplexing schemes gives priority to 
voice packets so your verbal communications go uninterrupted.  All of 
this relies on the connection being established between two 
MT2834PCSs.

Once a data connection is established through your Data Comm 
software (e.g., MultiExpress using AT commands),  a Digital 
Simultaneous Voice Data link is established by lifting the connected 
telephone accessory handset from its handset cradle. This method 
activates the Talk AnytimeTM feature, which establishes a voice and/or 
Digital Simultaneous Voice Data link anytime the handset is picked up.   

3.2.1   About Talk AnytimeTM

Using Multi-Techs' patent-pending Talk AnytimeTM  feature, you can 
switch to Digital Simultaneous Voice Data mode without having to first 
configure the modem.  Once a data link is established between two 
MT2834PCS modems, a  Digital Simultaneous Voice Data link begins 
by lifting the handset from the telephone accessory connected to your 
modem.  This engages your modem to "ring" the remote modem (you 
will hear the remote modem ringing through your handset just like a 
normal phone).  

When the remote side receives the "ring", the MT2834PCS  beeps 
twice every four seconds to get the remote user's attention.  When the 
remote user answers the call (picks up the handset), talking can begin 
using a Digital Simultaneous Voice Data link while still passing data.  
To end the Digital Simultaneous Voice Data link, simply hang-up the 
telephone.  The data link continues without interruption.

If at the end of conducting a voice connection, one side neglects to 
hang-up,  a "beeping" tone sounds 10 seconds afterwards.  This beeping 
tone occurs every 1/2 second to alert the user to hang-up the phone.

3.3     Voice Activation Commands

A voice modem must detect, recognize and act upon specific DTMF 
signals.  (The DTMF signals are tones used over the phone lines to 
indicate which key has been pressed on the phone's keypad.)  

Special firmware in the modem looks for the specific frequencies 
assigned to each number, and reports on which DTMF signal is present.  
Application software can use this information to perform tasks, such as 
activating  the answering machine, if the caller presses one number to 
leave a voice message, or go to fax mode if the caller selects another 
number to send a fax.

The special modem commands needed for controlling voice include 
selection of handset (speaker/microphone), control of voice volume, 
ambient noise sensitivity, and ring control.  

In typical Voice-Over-Data applications, the following commands will 
be the only configuring the user may have to perform:  

Ambient Noise Sensitivity Options   (>HV)                       
	
This command can be issued with one of fifteen sensitivity 
levels. Each value closest to zero makes the modem more sensitive to 
ambient noise (e.g. AT>HV0 makes the modem most sensitive to 
ambient noise). 
	AT>HV0  =       Most Sensitive.
	AT>HV14 =       Least Sensitive.
The factory default setting is >HV7. 

* Appendix C addresses commands which enable users to manually 
program the MT2834PCS for specific applications.  
Microphone Mode of Operation    (>M)                            
	
The attached telephone device can be put in one of two 
operational modes using this command. AT>M0 deactivates the 
telephone's mouthpiece to OFF mode.  AT>M2 activates the telephone's 
mouthpiece to ON mode.The modem must be issued a command to set 
its telephone mouthpiece volume (see >MV command) on the same line 
as this command, or the selected mouthpiece mode of operation will not 
be activated.  The mouthpiece accessory selected must match the 
earpiece accessory selected (i.e., AT>S0>M0  or AT>S2>M2). 
	AT>M0   =       Deactivates Telephone Mouthpiece.
	AT>M2   =       Activates Telephone Mouthpiece.
The factory default setting is >M2. 

Microphone Volume    (>MV)                                      
	
The MT2834PCS/c telephone's mouthpiece can be set to one 
of fourteen levels using this command.   AT>MV0  sets the mouthpiece 
activated by the AT>Mn command  to its lowest volume level, while 
AT>MV14 sets the mouthpiece to its highest volume level.
	AT>MV0  =       Lowest Volume Level.
	AT>MV14 =       Highest Volume Level.
Setting is User Selectable.    
	
Speaker Mode of Operation    (>S)                               
	
The attached telephone device can be put in one of two 
operational modes using this command. AT>S0 deactivates the 
telephone's earpiece to OFF mode. AT>S2 activates the telephone's 
earpiece to ON mode (factory default). The modem must be issued a 
command to set its earpiece volume (see >SV command) on the same 
line as this command, or the selected earpiece mode of operation will 
not be activated.
	AT>S0   =       Deactivates Telephone Earpiece.
	AT>S2   =       Activates Telephone Earpiece.
The factory default setting is >S2. 

Speaker Volume    (>SV)                                         
	
The MT2834PCS/c's speaker (or earpiece) can be set to one of 
ten levels using this command. AT>SV1 sets the earpiece activated by 
the AT>SVn command  to its lowest volume level, while AT>SV9 sets 
the earpiece to its highest volume level. 
	AT>SV0  =       Lowest Volume Level.
	AT>SV9  =       Highest Volume Level.
The factory default setting is >SV7.

4.1     Modem AT Commands
								
AT commands are the means by which you, and your 
communications software, are able to communicate with and configure 
your modem.  They enable you to establish, read, and modify 
parameters in addition to dialing.  The following provides a summary 
and brief explanation of the AT commands (primarily used in typical 
"data" mode) recognized by the MT2834PCS.   

COMMAND:        AT                                      
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Attention Code that precedes most command strings 
		except A/, A: and Escape Codes.

COMMAND:        Return                                  
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Pressing RETURN key executes most commands.

COMMAND:        A                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Answer call, even if no ring present.     

COMMAND:        $                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    This symbol placed in dialing string enables                                        
		the modem to detect AT&T's "call card"                  
		tones to access user's calling card to  
		originate an on-line connection.                               

COMMAND:        A/                                      
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Repeat last command.  (Do not precede this                                  
		command with AT.  Do not hit RETURN to execute.)

COMMAND:        A:                                      
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Continuous redial (10 redials in DOC units) of                                    
		last number until answered.                             
		(Not used Internationally or in the 
		MT2834PCSK.)

COMMAND:        $An                             
VALUES:         n = 0 or 1                      
DEFAULT:        $A0             
DESCRIPTION:    $A0 discards data during auto-reliable time period.                         
		$A1 buffers data during auto-reliable time period.

COMMAND:        #An                                     
VALUES:         n = 0 thru 3                            
DEFAULT:        #A0                     
DESCRIPTION:    #A0 selects initial handshake at  28,800 to 24000 to 21600                 
		to 19,200 to 16,800 to 14,400 to 12,000 to 9600  
		to 4800 to 2400 to 1200 to 300 bps.                                                                       
		#A1 selects initial handshake at  28,800 bps only.              
		#A2 selects initial handshake at  
		28,800 to 24000 to  21600 to 19,200 to 16,800 to 
		19,200 to 14,400 to 9600 to 4800bps                           
		#A3 selects initial handshake at 2400  to 1200 to 300 bps.

COMMAND:        Bn                                      
VALUES:         n = 0 or 1                              
DEFAULT:        B0                      
DESCRIPTION:    B0 selects V.21 for 300 bps operation.                                     
		B1 selects for 300 bps operation.                      
		(Not used Internationally or in the MT2834PCSK.)

COMMAND:        &Bn                                     
VALUES:         n = 0 or 1                              
DEFAULT:        &B0                     
DESCRIPTION:    &B0 means normal transmit buffer size.                                      
		&B1 means reduced transmit buffer size.

COMMAND:        &BSn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        &BS1            
DESCRIPTION:    &BS0 means maximum transmit block size of 64 characters.                             
		&BS1 means maximum transmit block size of 256 characters        
		(MNP mode)/128 characters (LAP-M mode).         
					
COMMAND:        $BAn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        $BA0            
DESCRIPTION:    $BA0 means speed conversion is on.                              
		$BA1 means speed conversion is off.

COMMAND:        &Cn                                     
VALUES:         n = 0, 1, 2 or 4                        
DEFAULT:        &C1             
DESCRIPTION:    &C0 forces Carrier Detect on.                                                                
		&C1 lets Carrier Detect act normally.                   
		&C2 lets Carrier Detect drop S24 time on disconnect.                             
		&C4 resets modem when Carrier Detect drops.

COMMAND:        Ds                                      
VALUES:         s = phone #                     
DEFAULT:        n/a             
DESCRIPTION:    Dial a telephone number "s", where s may                               
		include up to 60 digits or T, P, R, comma and ; characters.

COMMAND:        DsNd                                    
VALUES:         s = phone # and d = 0 thru 9    
DEFAULT:        n/a             
DESCRIPTION:    Store telephone number. To store, phone number "s" is
		entered and followed by N and then Directory 
		Number "d."

COMMAND:        &Dn                                     
VALUES:         n = 0 thru 3                    
DEFAULT:        &D2             
DESCRIPTION:    &D0 means DTR is ignored                                
		&D1means modem returns to command mode.
		&D2 lets modem react to DTR normally.   
		&D3 causes modem to reset to modem default parameters.

COMMAND:        $Dn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        $D0             
DESCRIPTION:    $D0 disables DTR Dialing.                                       
		$D1 enables DTR Dialing.

COMMAND:        %DFn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        %DF0            
DESCRIPTION:    %DF0 means V.34 Line Probe Data in Graph Format.                
		%DF1 means V.34 Line Probe Data in Table Format.

COMMAND:        %DPn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        %DP0            
DESCRIPTION:    %DP0 means do not read Line Probe Information from 
		DSP during handshaking.             
		%DP1 means read Line Probe Information from DSP 
		during handshaking.

COMMAND:        En                                      
VALUES:         n = 0 or 1                      
DEFAULT:        E1              
DESCRIPTION:    E0 means do not echo Command mode characters.                                      
		E1 means do echo Command mode characters.

COMMAND:        $EBn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        $EB0            
DESCRIPTION:    $EB0 enables 10 bit mode.                               
		$EB1 enables 11 bit mode.

COMMAND:        &En                                     
VALUES:         n = 0 thru 15                   
DEFAULT:        &E1, &E4, &E6, &E10, &E13, &E15                                
DESCRIPTION:    &E0 means no  error correction.                         
		&E1 means V.42 Auto-reliable Mode.      
		&E2 means V.42 Reliable Mode.                                           
		&E3 means no modem-initiated flow control.                                          
		&E4 means CTS modem-initiated flow control.             
		&E5 means Xon/Xoff modem-initiated flow control.                                                        
		&E6 means Xon/Xoff not passed through.                            
		&E7 means Xon/Xoff passed through.                      
		&E8 means Enq/Ack pacing off.   
		&E9 means Enq/Ack pacing on.                                                      
		&E10 means Normal Mode flow control off.                        
		&E11 means Normal Mode flow control on.         
		&E12 means Pacing off.          
		&E13 means Pacing on.                                   
		&E14 means data compression disabled.   
		&E15 means data compression enabled.

COMMAND:        %En                                     
VALUES:         n=0 thru 5                      
DEFAULT:        %E1             
DESCRIPTION:    %E0 = Modem Won't Escape.                                                             
		%E1 = +++ Method (default setting).                     
		%E2 = Break Method.                     
		%E3 = Either +++ or Break Method.                                         
		%E4 = No "OK" Response to +++                                         
		%E5 = "OK" Response to +++

COMMAND:        #Fn                                     
VALUES:         n = 0 thru 2                    
DEFAULT:        #F2             
DESCRIPTION:    #F0 means no fallback when on-line.                                 
		#F1 means fallback from  28800 to 2400 bps                      
		when on-line (increments of 2400 bps).  
		#F2 means fallback to 2400 bps from 28.8K                                     
		bps/fall forward if line improves (increments          
		of  2400 bps).

COMMAND:        &Fn                                     
VALUES:         n = 0, 8 or 9                   
DEFAULT:        &F8             
DESCRIPTION:    &F loads factory default values from ROM.                                          
		&F8 reads factory default values when &F is issued.             
		&F9 reads parameters stored in nonvolatile              
		memory when &F is issued.

COMMAND:        $Fn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        $F1             
DESCRIPTION:    $F0 means do not fall back to normal connect if CR 
		received.                         
		$F1 means fall back to normal connect if CR received.

COMMAND:        &Gn                                     
VALUES:         n = 0, 1 or 2                   
DEFAULT:        &G0             
DESCRIPTION:    &G0 turns off CCITT guard tones.                                
		&G1 turns on CCITT 550 Hz guard tone.           
		&G2 turns on CCITT 1800 Hz guard tone.                                       
		(Not used Internationally or in the MT2834PCSK.)

COMMAND:        Hn                                      
VALUES:         n = 0 or 1                      
DEFAULT:        n/a             
DESCRIPTION:    H0 means Hang Up (go on hook).                                     
		H1 means Go Off Hook.

COMMAND:        $Hn                                     
VALUES:         n = 1 thru 3                    
DEFAULT:        Read Only Command                                 
DESCRIPTION:    $H1 brings up Help Screen #1.                           
		$H2 brings up Help Screen #2.           
		$H3 brings up Help Screen #3.

COMMAND:        In                                      
VALUES:         n = 0,1, 2 or 5                 
DEFAULT:        Read Only Command                                 
DESCRIPTION:    I0 requests modem ID #.                                 
		I1 requests firmware revision #.                        
		I2 for MTS internal use.                        
		I5 outputs DSP version.

COMMAND:        L                                       
VALUES:         5, 6, 7, 8, 9, 10 and 11                
DEFAULT:        Read Only Command                                   
DESCRIPTION:    L5 lists all current operating parameters.         
		L6 lists all current S-Register values.                                         
		L7 lists additional parameters.                                             
		L8 lists current on-line diagnostics.                           
		L9 displays Signal Strength Information.                
		L10 displays Signal to Noise Ratio Information.               
		L11 displays Noise Information.

COMMAND:        #Ln                                     
VALUES:         n = 0 thru 3                    
DEFAULT:        #L0             
DESCRIPTION:    #L0 means modems negotiate V.42 Mode.                   
		#L1 means MNP on and LAP-M off.         
		#L2 means LAP-M on and MNP off.                                            
		#L3 means no detection phase but go directly to LAP-M.

COMMAND:        $MBn                                    
VALUES:         n = speed                       
DEFAULT:        $MB28800 bps    
DESCRIPTION:    $MB75 selects CCITT V.23 mode.                          
		$MB300 selects 300 bps on-line.                 
		$MB1200 selects 1200 bps on-line.               
		$MB2400 selects 2400 bps on-line.       
		$MB4800 selects 4800 bps on-line.                                    
		$MB9600 selects 9600 bps on-line.                               
		$MB14400 selects 14400 bps on-line              
		$MB19200 selects 19200 bps on-line                                                    
		$MB28800 selects 28800 bps on-line

COMMAND:        &Mn                                    
VALUES:         n = 0 or 1                     
DEFAULT:        &M0             
DESCRIPTION:    &M0 selects Async when on-line.                         
		&M1 selects Sync when on-line.

COMMAND:        Nd                                      
VALUES:         d = 0 thru 9                    
DEFAULT:        n/a             
DESCRIPTION:    Dial stored telephone number "d" (Do not                             
		include the letter D in this command.)

COMMAND:        NdNe                                    
VALUES:         d = 0 thru 9; e = any other number 0 thru 9                        
DEFAULT:        n/a             
DESCRIPTION:    Number Linking. If first number dialed is 
		busy, another stored number may be                      
		automatically dialed. In example, stored                                          
		number d is dialed, and if busy, stored number e is dialed.

COMMAND:        O                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Exit Command Mode and go into On-Line Mode.

COMMAND:        P                                               
VALUES:         n/a                                     
DEFAULT:        Tone Dial                               
DESCRIPTION:    Modem will pulse-dial numbers following the P.

COMMAND:        &Pn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        &P0             
DESCRIPTION:    &P0 means 60-40 pulse ratio.                                                  
		&P1 means 67-33 pulse ratio.

COMMAND:        Qn                                      
VALUES:         n = 0, 1 or 2                   
DEFAULT:        Q0              
DESCRIPTION:    Q0 means Result Codes sent.                                     
		Q1 means Result Codes will be suppressed (quiet).      
		Q2 means Dumb Answer Mode.

COMMAND:        &Qn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        &Q0             
DESCRIPTION:    &Q0 selects Multi-Tech command set.                    
		&Q1 selects AT command set.

COMMAND:        Rn                                      
VALUES:         n = 0 or 1                      
DEFAULT:        R0              
DESCRIPTION:    R0 means modem will not reverse modes.                  
		R1 means modem will reverse modes.

COMMAND:        &Rn                                     
VALUES:         n = 0, 1 or 2                   
DEFAULT:        &R1             
DESCRIPTION:    &R0 lets Clear to Send act normally.                    
		&R1 forces Clear to Send on.                                                     
		&R2 drops for 1 second on disconnect.

COMMAND:        $Rn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        $R0             
DESCRIPTION:    $R0 means disconnect after 12 retransmits.                              
		$R1 means do not disconnect after 12 retransmits.

COMMAND:        &RFn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        &RF1            
DESCRIPTION:    &RF0 selects CTS follows RTS.                                                        
		&RF1 selects CTS to act independently

COMMAND:        Sr=n                                    
VALUES:         r = 0-11, 13, 15-17, 24-26, 29, 30, 32, 34, 36, 37, 48      
DEFAULT:        n/a                     
DESCRIPTION:    Sets value of S-Register "r" to value of "n",  where "n" is                     
		entered in decimal format.

COMMAND:        Sr?                                     
VALUES:         r = 0-11, 13, 15-17, 24-26, 29, 30, 32, 34, 36, 37, 48      
DEFAULT:        n/a                     
DESCRIPTION:    Reads value of S-Register "r" and displays value in 3-digit                       
		decimal format.

COMMAND:        $SBn                                    
VALUES:         n = speed                       
DEFAULT:        $SB115200 bps   
DESCRIPTION:    $SB300 selects 300 bps at serial port.                         
		$SB1200 selects 1200 bps at serial port.        
		$SB2400 selects 2400 bps at serial port.                                 
		$SB4800 selects 4800 bps at serial port.                        
		$SB9600 selects 9600 bps at serial port.        
		$SB19200 selects 19,200 bps at serial port.                                     
		$SB38400 selects 38,400 bps at serial port                               
		$SB57600 selects 57600 bps at serial port.                      
		$SB115200 selects 115200 bps at serial port.

COMMAND:        &SFn                                    
VALUES:         n = 0 or 1                      
DEFAULT:        &SF0            
DESCRIPTION:    &SF0 selects DSR follows CD.                                    
		&SF1 selects DSR independent.

COMMAND:        &Sn                                     
VALUES:         n = 0, 1 or 2                   
DEFAULT:        &S1             
DESCRIPTION:    &S0 forces Data Set Ready On.                                                      
		&S1 lets Data Set Ready act normally.                   
		&S2 Data Set Ready drop is regulated by S24 on disconnect.      

COMMAND:        T                                       
VALUES:         n/a                             
DEFAULT:        Tone Dial               
DESCRIPTION:    Modem will tone-dial numbers following the T.

COMMAND:        &Tn                                     
VALUES:         n = 4 or 5                      
DEFAULT:        &T5             
DESCRIPTION:    &T4 means Enable Response to Request for 
		Remote Digital Loopback.                                        
		&T5 means Disable Response to Request for       
		Remote Digital Loopback.

COMMAND:        #Tn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        #T1             
DESCRIPTION:    #T0 turns off Trellis Coded Modulation                                                       
		#T1 turns on Trellis Coded Modulation

COMMAND:        Un                                      
VALUES:         n = 0, 1, 2, or 3                       
DEFAULT:        n/a             
DESCRIPTION:    U0 places modem in Analog Loop Originate Mode.                     
		U1 places modem in Analog Loop Answer Mode.     
		U2 places  modem  in  Remote Digital Loopback                                        
		test mode.                                              
		U3 places modem in Local Digital Loopback Test Mode.

COMMAND:        Vn                                      
VALUES:         n = 0 or 1                      
DEFAULT:        V1              
DESCRIPTION:    V0 means Result Codes sent as digits(terse response).                              
		V1 means Result Codes sent as words (verbose response).

COMMAND:        #Vn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        #V0             
DESCRIPTION:    User can bypass V.32terbo handshaking process.                                               
		#V0 means V.32terbo enabled in answer mode.                           
		#V1 means V.32terbo disabled in answer mode.

COMMAND:        W                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Wait for new dial-tone.

COMMAND:        &Wn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        &W1             
DESCRIPTION:    &W0 causes modem to store its current parameters in non-                    
		volatile RAM, and modem will load these for future ses- 
		sions instead of reading factory ROM 
		defaults, unless &F command used.   
		&W1 causes modem to not store parameters.

COMMAND:        Xn                                      
VALUES:         n = 0, 1, 2, 3 or 4                     
DEFAULT:        X0              
DESCRIPTION:    X0 selects Basic Result Codes (w/o CONNECT 1200,CONNECT 2400).          
		X1 selects Extended Result Codes (w/CONNECT 1200,                  
		CONNECT 2400).                                  
		X2 selects Standard AT Command set with NO DIAL TONE.               
		X3 selects Standard AT Command set with BUSY.                              
		X4 selects Standard AT Command set with NO DIAL        
		TONE and BUSY.

COMMAND:        #Xn                                     
VALUES:         n = 0 or 1                      
DEFAULT:        #X0             
DESCRIPTION:    #X0 selects single XOFF character sent until XON level  
		returns.                                       
		#X1 selects multiple XOFF characters after  
		buffer level is full.

COMMAND:        Yn                                      
VALUES:         n = 0 or 1                      
DEFAULT:        Y0              
DESCRIPTION:    Y0 disables sending or responding to long space "break".        
		Y1 enables sending or responding to long space "breaks".

COMMAND:        Z                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    All configuration parameters are reset to default values.

COMMAND:        , (Comma)                               
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Causes pause during dialing.

COMMAND:        ;(Semi-Colon)                          
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Causes return to Command Mode after dialing.

COMMAND:        !  (Exclamation)                               
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Causes modem to flash On-Hook.

COMMAND:        @                                       
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Causes modem to wait for ringback, then 5 seconds of                    
		silence before processing next part of command.

COMMAND:        +++AT<CR>                               
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    In-band Escape Sequence.  Places modem in Command
		mode while still remaining On-  Line. Enter +++  
		followed by the letters A and T, up to ten command 
		characters, and a RETURN. 

COMMAND:        BREAK AT<CR>                    
VALUES:         n/a             
DEFAULT:        n/a     
DESCRIPTION:    Out-of-band Escape Sequence. Places modem in Command    
		mode while still remaining On- Line. Not  
		preceded by AT. Enter a BREAK signal, followed by the          
		letters A and T, up to sixty command characters, and hit 
		RETURN.         
							
4.1.1 Callback Security/Remote Configuration Commands                   
			
COMMAND:        #DBn                                    
VALUES:         n= 0, 1, or  2                  
DEFAULT:        #DB0            
DESCRIPTION:    #DB0 disables Callback Security and answering Yes to
		the prompt turns off Callback Security and erases stored                           
		phone numbers and passwords.  Answering No to the                                 
		prompt aborts the command.                                                 
		#DB1 activates remote and local password security.                      
		#DB2 activates remote password security.

COMMAND:        #CBNyyxxxxxx                            
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Callback password with xxxxxx being callback password 
		and yy being the memory location.  Callback password xxxxxx         
		must start with a non-numeric character and 
		upper/lower case sensitive.  Callback password 
		xxxxxx must be a minimum of 6 and maximum 
		of 10 characters.  yy memory locations are from 0 to 29.  
		Must T (tone) dialing in string.

COMMAND:        + - Dxxxxxx???Nxx                       
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Callback Phone Numbers xxxxxx with the + preceding the           
		phone number indicating the  callback modem phone number        
		for the corresponding password at the same memory 
		location.  The (-) preceding the phone number 
		enables direct entry when the caller uses the 
		correct password without the callback modem 
		having to return the call.  The ??? entry at the end 
		of the phone number represents an extension added               
		to the main phone number.  The Nxx is the memory location       
		of the callback phone number and password.

COMMAND:        #Pn                                     
VALUES:         n= 0, 1, or 2                   
DEFAULT:        #P0             
DESCRIPTION:    Parity of the prompt messages sent by the callback modem.                 
		#P0 is no parity                                               
		#P1 is odd parity                              
		#P2 is even parity

COMMAND:        #RCBNxx                         
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Erases the callback password stored at memory location xx.             
		Memory locations are 0 to 29.

COMMAND:        #RDNxx                          
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    Erases the callback phone number stored at memory loca-                
		tion xx.  Memory locations are 0 to 29.
				
Password  Commands 

COMMAND:        #Ixxxxxxxxxx                            
VALUES:         n/a                     
DEFAULT:        #IMULTITECH     
DESCRIPTION:    Login Password is any keyboard characters (x) (upper/lower      
		case sensitive), minimum 6  and maximum 10 characters.                     
		The default Login Password is MULTI-TECH.

COMMAND:        #Syyyyyyyyyy                            
VALUES:         n/a                     
DEFAULT:        #SMODEMSETUP                            
DESCRIPTION:    Set-up Password is any keyboard characters (y) (upper/                  
		lower case sensitive), minimum 6  and maximum 10 charac-                       
		ters.  The default Set-up Password is MODEMSETUP.

4.1.2    V.25bis Commands

COMMAND:        $Vn                                     
VALUES:         n= 0, 1, 2, 5, or 6                     
DEFAULT:        $V0             
DESCRIPTION:    $V0 returns modem to AT command mode when in V.25bis mode.                                        
		$V1 enables V.25bis mode of operation.                                              
		$V2 allows modem to receive one V.25bis command while               
		in AT command mode without leaving AT command mode.                           
		$V5 DSR follows DTR in V.25bis mode.                                           
		$V6 DSR does not follow DTR in V.25bis mode.

COMMAND:        CLAmm                                   
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Clears the phone number memory location mm.  Phone                     
		numbers are stored in memory locations 00 to 19.

COMMAND:        CSPs                                    
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    The CSP command will change the serial baud rate of your                        
		modem by entering CSPsssss where sssss can equal: 
		CSP0300 - 300 bps
		CSP1200 - 1200 bps
		CSP2400 - 2400 bps      
		CSP4800 - 4800 bps
		CSP9600 - 9600 bps
		CSP19200 - 19200 bps
		CSP38400 - 38400 bps
		CSP57600 - 57600 bps                            
		CSP115200 - 115200 bps
							
COMMAND:        CRNdd                           
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Dials phone number dd where dd can be up to 20 characters                   
		(0 through 9, *, #, P, T and :). Phone number is checked        
		against the Delayed and Forbidden Number lists before                            
		dialed.

COMMAND:        CRNdd;nn                                
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Dials dd same as CRN Command and ignores nn identifica-                  
		tion string.

COMMAND:        CRSmm                           
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Dial stored phone number at memory location mm.  Phone                    
		numbers are stored in memory locations 00 to 19.  Phone         
		number is checked against the Delayed and Forbidden                               
		Number lists before dialed.

COMMAND:        PRNmm;dd                                
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Store phone number in memory location mm followed by a              
		semicolon (;) and the phone number dd in which you wish         
		to store.

COMMAND:        RLN                                     
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Displays all phone numbers stored in memory.

COMMAND:        RLD                                     
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Displays the delayed phone numbers stored in memory.  The                    
		delayed phone numbers listing can contain up to eight   
		phone numbers.

COMMAND:        RLF                                     
VALUES:         n/a                             
DEFAULT:        n/a                     
DESCRIPTION:    Displays the forbidden phone numbers stored in memory.                       
		This listing can be up to eight phone numbers.

COMMAND:        DIC or CIC                              
VALUES:         n/a                     
DEFAULT:        n/a             
DESCRIPTION:    The disregard or connect to incoming calls commands are                     
		used for auto-answer operations. DIC stops the modem    
		from answering incoming calls. CIC causes the modem to                            
		answer incoming calls.  

4.2    S-Registers  
								
Certain Command Mode configurations are stored in memory 
registers called, S-Registers.  The S command is used to assign a value 
to, and to read the current value of an S-Register. To assign a value to 
an S-Register, enter the letter S, followed by the S-Register number and 
an equals sign (=), and then a decimal response to the message 
"ENTER THE NEW VALUE IN DECIMAL FORMAT".  To read an 
S-Register value, enter the letter S followed by the S-Register number 
and a question mark (?), then hit RETURN. To verify that the S-
Register value was entered correctly, enter for example, ATS8? and hit 
RETURN. You should receive a response of the assigned value given to 
that S-Register.

S0
Number of Rings Until Modem Answers     
	Unit:   1 ring          
	Range:  0-255
	Default:        1       
	Description:    Sets the number of rings before the modem 
answers.

S1
Rings Which Have Occurred                       
	Unit:   1 ring  
	Range:  0-255   
	Default:        0               
	Description:    Counts the number of rings that have 
occurred. 

S2
Escape Code Character
	Unit:   ASCII Character 
	Range:  0-127                           
	Default:        43 (+ sign)     
Description:    Defines the escape code character.

S3
Return Character                
	Unit:   ASCII Character 
	Range:  0-127
	Default:        13
	Description:    Defines the character recognized as Carriage 
Return (RETURN) or "Enter". 

S4
Line Feed Character             
	Unit:   ASCII Character 
	Range:  0-127   
	Default:        10                      
	Description:    Defines the character recognized as LINE 
FEED. 

S5
Backspace Character
	Unit:   ASCII Character 
	Range:  0-127   
	Default:        8
Description:    Defines the character recognized as BACKSPACE. 

S6
Wait Time for Dial Tone
	Unit:   1 second
	Range:  2-255, 4-255**, 4-7***  
	Default:        2, 4**, 4***
	Description:    Sets the time the modem waits after the 
RETURN key is pressed before executing a dial command.


* Value for International and DOC units                         
** Value for International Units only           
*** Value for BABT models only 

S7
Time for Carrier (Abort Timer)
	Unit:   1 second
	Range:  1-255, 1-45*, 1-55***   
	Default:        45, 55***
	Description:    Defines the Abort Timer (lack of carrier) 
delay time.                             

S8
Pause Time for Comma
	Unit:   1 second
	Range:  0-255, 4-255**, 4-7***  
	Default:        2, 4**, 4***
	Description:    Sets the length of the pause caused by a 
comma inserted in a dialing command. 

S9
Carrier Detect Response Time
	Unit:   100 mSec.
	Range:  1-255
	Default:        6
	Description:    Sets the time delay for when the modem first 
detects a valid incoming carrier signal and when the modem turns on its 
Carrier Detect circuit. 

S10
Carrier Loss Disconnect Delay Time
	Unit:   100 mSec.
	Range:  0-255
	Default:        7
	Description:    Sets the time a carrier signal must be lost 
before the modem disconnects. 

S11
Tone Dialing: Tone Spacing and Duration
	Unit:   1 mSec.
	Range:  1-255, 80-255*,80-255***        
	Default:        70, 80*,80***
	Description:    Sets the time duration of spacing between 
tone in tone-dialing.

S13
Remote Configuration Escape Character
	Unit:   ASCII Character
	Range:  0-127
	Default:        37 (% sign)
	Description:    Defines the remote configuration escape 
character. 
								
S15                                                     
Callback Time Delay
	Unit:   Seconds
	Range:  10-255
	Default:        20              
	Description:    S15 defines the time delay for Callback 
attempts after initial passwords have been exchanged between modems.

S16
Callback Attempts
	Unit:   1 Attempt
	Range:  1-255, 1-2***
	Default:        4, 2*** 
	Description:    S16 Callback defines the number of attempts 
allowed after initial passwords have been exchanged between modems.

* Value for International and DOC units                         
** Value for International Units only           
*** Value for BABT models only 

S17
Changing Break Time
	Unit:   10 mSec.
	Range:  0-2.5 sec
	Default:        250 
	Description:    S17 defines the break time (space) to local 
PC.
	
S24
PBX/CBX Disconnect Drop Time for DSR/CTS/CD
	Unit:   50 mSec.
	Range:  0-255
	Default:        20 
	Description:    Defines DSR/CTS/CD dropout time. The 
default of 20 equals one second.

S25
DTR Dropout Time 
	Unit:   100 mSec.
	Range:  0, 1 through 255
	Default:        0 
	Description:    Defines DTR dropout time. 0 default equals 
50ms.

S26
Failed Password Attempts
	Unit:   1 failed attempt
	Range:  0-255 
	Default:        0 
	Description:Counts the number of times there has been a failed 
password attempt. 

S29
Local Inactivity Timer
	Unit:   minutes
	Range:  1-255 
	Default:        20
	Description:    Defines the amount of idle time that can 
elapse between AT commands after the SETUP password has been 
entered.                                                                                                          

S30
Inactivity Timer
	Unit:   1 minute
	Range:  0-255 
	Default:        0 
	Description:    Inactivity timer used to disconnect the 
modem.

S32
Time Elapse for Escape Sequence
	Unit:   1 second
	Range:  0-255 
	Default:        20 
	Description:    Sets the duration in which modem waits for 
a <CR> to be entered during escape sequence execution. 

S34
Buffer Length of Command Mode...After On-line Escape Sequence
	Unit:   ASCII Character
	Range:  0-60
	Default:        10 
	Description:    Sets buffer length of command mode after 
on-line escape sequence.                                                
							
S36
Time Between DTR Inactive and Modem Off-Hook
	Unit:   1 Second
	Range:  0-255 seconds
	Default:        0
	Description:    Sets the time between DTR inactive (low) 
and the modem going off-hook.  The DTR Busy-out feature is disabled 
with S36=0.

S37
Time Between DTR Active and Modem On-Hook
	Unit:   1 Second
	Range:  0-255 seconds
	Default:        5
	Description:    Sets the time between DTR being active and 
the modem going on-hook (not busy).

S48
Program V.34 Connect Speeds     
	Unit:   N/A             
	Range:  28, 26, 21,19,16,14,12, 96 and 48
	Default:        0       
	Description:    Defines which speed modem connects within 
V.34 mode scope (e.g., S48 = 21 means maximum connect speed is 
21.6K).  This register compensates for line conditions that will not 
support higher V.34 speeds (e.g., 28K, 26.4K, 24K...).  The modem 
default is a value of 0, which indicates a connection attempt of 28.8K. 
								
4.3   Result Codes  
								
The MT2834PCS Command mode provides you with several 
responses, or "Result Codes", that can aid you in Command mode 
operation.  These Result Codes are displayed on your video monitor.
AT&Q0  selects Multi-Tech responses with Reliable/Compression 
modifiers.  The terse result code for CONNECT 2400 is 9.  
AT&Q1 selects Standard AT command set responses.  The terse result 
code for CONNECT 2400 is 10.

The following tables list result codes generated by the &Q command. 
		
Table 4-1 &Q0 "Multi-Tech" Result Codes
TERSE           VERBOSE
0               OK
1               CONNECT
2               RING
3               NO CARRIER
4               ERROR
5       *       CONNECT 1200
6               NO DIALTONE
7               BUSY
8               NO ANSWER
9       *       CONNECT 2400
11      *       CONNECT 4800
12      *       CONNECT 9600
13      *       CONNECT 14400           
19      *       CONNECT 19200           
21      *       CONNECT 21600           
24      *       CONNECT 24000           
26      *       CONNECT 26400           
28      *       CONNECT 28800           

* With error correction on, RELIABLE (or R) is added to these result 
codes. With data compression on, COMPRESSION (or C) is added.
		
Table 4-2 &Q1 "Standard AT" Result Codes
TERSE           VERBOSE             
0               OK
1               CONNECT
2               RING
3               NO CARRIER
4               ERROR
5               CONNECT 1200
6               NO DIAL TONE
7               BUSY
8               NO ANSWER       
10              CONNECT 2400
11              CONNECT 4800
12              CONNECT 9600
13              CONNECT 14400                   
19              CONNECT 19200                   
21              CONNECT  21600                  
24              CONNECT  24000                  
26              CONNECT  26400                  
28              CONNECT  28800                                  

*Error Correction/Data Compression modifiers are not displayed with 
Standard AT Result Codes. 

4.3.1     AT Commands and S-Register Summary

The vast majority of installations are similar, with the MT2834PCS 
being used to dial up a remote installation where the call is 
automatically answered.  Your MT2834PCS has a default configuration 
to dial another 28,800 bps modem that support error correction, data 
compression and flow control.  If the answering modem is not 
compatible, the MT2834PCS can match protocols, provided the 
protocols are industry standard (i.e., ITU-T, AT&T or Bell) and not 
proprietary.  

The &W command, used in conjunction with specific other AT 
commands and S-Registers, can reconfigure the MT2834PCS to 
conform to a specific application.  The MT2834PCS can store its 
configuration parameters and  S-Register values in its nonvolatile 
memory.

The command AT&W0 (or AT&W) causes the modem to store its 
current parameters in its nonvolatile RAM.  The command also sets  the 
modem upon power up, or when it is reset with an ATZ command, the 
modem reads all its configuration and S-Register parameters from 
RAM, and not from the factory settings in ROM (note you may recall 
factory installed defaults by entering AT&F8&W0).  The &W 
command changes the configuration parameters stored in RAM that you 
specifically intend to alter.  All other default parameters remain 
unchanged.

The AT&W1 command sets the modem so that it does not store its 
parameters in RAM, and on power up or when an ATZ command is 
issued, parameters are read from the factory default settings in ROM.
Before  using the &W command, you may want to view the modem's 
current operating parameters.  Use the ATL5, ATL6 and ATL7 
commands to display the current modem configuration.

5.1    Introduction 

Each time you power up the MT2834PCS, it performs an automatic 
self- test to ensure proper operation. The MT2834PCS also has three 
diagnostic test features: Local Analog Loopback, Digital Loopback 
(remote/automatic) and Digital Loopback (local/manual). 

A loopback test involves entering data from your PC and looping that 
data through the circuits of your modem and/or a remote modem.  
When the loop has been completed, the original data entered should 
match the data received back on your PCs monitor after the test.

The Local Analog Loopback Test allows you to verify that the modem's 
transmitter and receiver circuits are functioning properly.
The Digital Loopback Test (local/manual) allows you to verify that the 
remote computer or terminal, the remote modem, serial ports, the 
telephone line and the local modem are functioning properly. 
The Digital Loopback Test (remote/automatic) allows you to verify that 
the local computer or terminal, the two modems and the transmission 
line between them are functioning properly.

In asynchronous mode, upon completion of testing, enter either Escape 
Sequence, +++AT<CR> or <BREAK>AT<CR>.

Note: All loopback tests will operate at all speeds except 300 bps.

5.2    Local Analog Loopback Test/V.54 Loop 3 

In this test, data from your computer or terminal is sent to your  
modem's transmitter, converted into analog form, looped back to the 
receiver, converted into digital form and then received back at your 
monitor for verification.  No connection to the phone line is required.

The test procedure is as follows: 

1.      Connect the modem to your computer. With your 
communication software, set the desired baud rate.  

2.      Type ATU0 (or ATU) and hit ENTER. This places your 
modem in Analog Loopback mode, in the Originate mode. The modem 
is now out of the Command mode and in a pseudo On-Line mode. 

3.      Once you receive a connect message (if responses are 
enabled), enter data from your keyboard. For this test, typing multiple 
upper case "U" characters is a good way to send an alternating test 
pattern of ones and zeros. 

4.      For a more complete test, you should also test the modem in 
Answer mode. To do this, you must "escape" from Originate mode by 
entering an Escape Sequence (+++AT<CR> or <BREAK>AT<CR>) . 
Then type ATU1 and hit ENTER to place the modem in Analog 
Loopback mode, in the Answer mode. Then repeat step 3. 

5.      When testing is completed, you may exit Answer mode by 
entering an Escape Sequence (+++AT<CR> or <BREAK>AT<CR>), 
which returns the modem to Command mode. 

6.      Your modem passes this test if the data entered from your 
keyboard are the same as the data received on your monitor.  If 
different data is appearing on your monitor, your modem is probably 
causing the problem, although it could also be your computer. If your 
modem passes this test, but you are receiving errors while On-line, the 
remote modem or the phone line could be at fault. 

5.3    Digital Loopback Test/V.54 Loop 2 (Local/                        
Manual)

In this test, your modem must be On-Line with another modem that can 
respond to a request for Digital Loopback, such as another 
MT2834PCS. The Digital Loopback Test is an on-line test that loops 
data sent from one modem across the phone line to another modem, 
then back to the first modem.

There are two ways to put a modem into Digital Loopback mode.
	1.  Locally or Manually, described here in section 5.3.
	2.  Remotely or Automatically, see section 5.4.

Note: The Digital Loopback Tests can only be used with the modem in 
Normal mode (error correction off). 

In this test the local modem is placed in Digital Loopback mode.  Data 
is entered and transmitted from the remote modem (which is not in 
digital loopback mode), sent across the phone line to the local modem 
and looped back to the remote modem. 

The test procedure is as follows: 

1.      Go into Terminal mode. Type AT and hit ENTER; you should 
get an OK message. 

2.      Dial the remote modem by entering the Dial command and the 
phone number, to establish On-line mode. 

3.      Type the Escape Sequence (+++AT<CR> or 
<BREAK>AT<CR>) which brings your modem into Command mode, 
while still maintaining the pseudo On-line mode with the remote 
modem. 

4.      Type ATU3 from the local PC and hit ENTER. Once you receive an 
OK message from your modem (if responses are enabled), the local 
modem is placed in Digital Loopback mode.

5.      Data is typed from the remote keyboard. For this test, typing 
multiple upper case "U" characters is a good way to send an alternating 
test pattern of ones and zeros. The data received by the local modem 
will enter its analog receiver, be converted to digital data, be 
reconverted into analog, and then looped through its transmitter back to 
the remotemodem. Your modem passes this test if the data entered from 
the remote keyboard is the same as the data received on the remote 
monitor.   

6.      When testing is complete, you may end the test by typing an 
Escape Sequence (+++AT<CR> or <BREAK>AT<CR>) to bring your 
modem into Command mode. The modem should respond with an OK 
message. If you wish to stay On-line with the remote modem for normal 
data transmission, type AT0 and hit ENTER. If you wish to terminate 
the call, type ATH and hit ENTER to hang up. 

5.4    Digital Loopback Test/V.54 Loop 2(Remote/                        
Automatic)

In this test, your modem must be On-line with another modem set up to 
respond to a request for Digital Loopback, such as another 
MT2834PCS. With the MT2834PCS, this ability to respond is 
controlled by the &T command. AT&T4 enables the response to Digital 
Loopback Test (remote/automatic). AT&T5 disables the response. The 
modem defaults to disable on power up, so this must be changed on the 
remote modem before the modem will respond to a request for the 
Digital Loopback Test (remote/automatic). 

Initiate the Digital Loopback Test (remote/automatic) with the ATU2 
command which automatically places the remote modem in digital 
loopback mode. Data from your computer or terminal are transmitted 
through your modem, and over the phone line to the remote modem, 
where they are then looped back to your modem.  See Figure 5-3.

The test procedure is as follows:

1.      Go into Terminal mode. Type AT and hit ENTER; you should 
get an OK message. 

2.      Dial the remote modem by entering the Dial command and the 
phone number, to establish On-line mode. 

Note: The &T4 command must be set on the remote modem to run this 
test.

3.      Type the Escape Sequence (+++AT<CR> or 
<BREAK>AT<CR>) which brings your modem into Command mode, 
while still maintaining the connection with the remote modem. 

4.      Type ATU2 and hit ENTER. The local modem responds to 
this command by transmitting an unscrambled marking signal, which 
causes the remote modem to place itself in Digital Loopback mode.  
Then the local modem exits Command mode and enters pseudo On-line 
mode.

5.      Type data from your keyboard. For this test, typing multiple upper 
case "U" characters is a good way to send an alternating test 
pattern of ones and zeros. The data received by the remote modem will 
enter its analog receiver, be converted to digital data, be reconverted 
into analog, and then looped through its transmitter back to the local 
modem. Your modem passes this test if the data entered from the local 
keyboard is the same as the data received on your monitor.   

5.5     Synchronous Mode Testing

The following tests must be run with your modem in Synchronous mode 
(DIP Switch #12 in the Up (OPEN) position), DIP Switch #9 controls 
the modem's Synchronous mode testing function. (Refer to Chapter 2 
for DIP Switch information.) The test procedures for Synchronous 
mode are different from those for Asynchronous mode. In Synchronous 
mode, you cannot access the modem's AT commands.  

With DIP Switch #9, you can perform either the Digital Loopback Test 
(remote/automatic) or the Digital Loopback Test (local/manual) in 
Synchronous mode, as described in the following sections. There is also 
a Local Analog Loopback Test, documented in section 5.6. 
  
5.6    Local Analog Loopback Test (Synchronous                  
Mode)

This test diagnoses the connection between your MT2834PCS and your 
computer or terminal. In Local Analog Loopback Test mode, data 
entered at the local computer or terminal are sent through the local 
modem's transmit and receive circuits (much like entering an ATU or 
ATU1 command in Asynchronous mode). You then compare the test 
characters on your monitor with the characters you typed. If the 
characters don't match, check your computer's COM port setting, then 
verify your communication software's configuration. 

To initiate the Local Analog Loopback Test, with the modem in 
Synchronous mode:

1.      Enter AT&M1U. This first switches your modem from 
asynchronous to synchronous mode, and places it into the Analog 
Loopback/Originate mode.  The modem is now out of the Command 
mode and in the pseudo On-Line mode.

2.      Once you receive a connect message (if responses are enabled), enter 
data from your keyboard.  For this test, typing multiple upper case "U" 
characters is a good way to send an alternating test pattern of ones and 
zeros. 

3.      For a more complete test, you should also test the modem in 
Answer mode. To do this, Type the Escape Sequence (+++AT<CR> or 
<BREAK>AT<CR>) which brings your modem into Command mode, 
while still maintaining the connection.  Then type AT&M1U1 and hit 
ENTER to place the modem in Analog Loopback mode, in the Answer 
mode. Then repeat step 2. 

5.7    Digital Loopback Test (Local/Manual)                     
	(Synchronous Mode)

This test must be run when you have a data connection with another 
modem. If a Local Analog Loopback Test resulted in errors, and this 
test passes without errors, then the problem exists in your computer-to-
modem connection. In Digital Loopback Test (local/manual) mode, 
data passed from the remote modem's transmit circuit are looped back 
from the local modem and are received at the remote modem's receive 
circuit.

First make certain that you are set up for Synchronous operation by 
placing DIP-Switch #12 in the UP position. To initiate the Digital 
Loopback Test (local/manual), DIP-Switch #9 must be in the UP 
position, and the Answer/Orignate switch (front of the modem) must be 
toggled to the UP position. Once you receive an OK message from your 
modem (if responses are enabled), the local modem is placed in Digital 
Loopback mode.

To exit the Digital Loopback Test (local/manual), toggle the Answ/Orig 
switch to the Answer position (UP).

5.8     Digital Loopback Test (Remote/Automatic)                         
	(Synchronous Mode)

This test must be run when you have a data connection with another 
modem.  In this test, data is passed to the remote modem and is looped 
back to the local  modem (as if an ATU2 command was issued in 
Asynchronous test mode).  This lets you test the 
local and remote modem's transmit and receive circuits, as well as your 
computer's serial COM port and the phone lines. If the test results in a 
mismatch of entered/received data, the Local Analog Loopback Test should 
be performed on both the remote and local modems. If that test is 
successful, the problem may be the phone lines. 

First make certain that you are set up for Synchronous operation by 
placing DIP-Switch #12 in the UP position. To initiate the Digital 
Loopback Test (remote/automatic), DIP-Switch #9 must be in the 
DOWN position, and the Answer/Orignate switch (front of the modem) 
must be toggled to the UP position.  Once you receive an OK message 
from your modem (if responses are enabled), the local modem is placed 
in Digital Loopback mode. To exit the Digital Loopback Test 
(remote/automatic), toggle the Answ/Orig switch to the Answer position 
(UP).

Appendix A

FCC Regulations for Telephone Line Interconnection

1.      This equipment complies with Part 68 of the Federal 
Communications Commission (FCC) rules. On the outside surface of 
this equipment is a label that contains, among other information, the 
FCC registration number and ringer equivalence number (REN). If 
requested, this information must be provided to the telephone company.

2.      As indicated below, the suitable jack (Universal Service Order 
Code connecting arrangement) for this equipment is shown. If 
applicable, the facility interface codes (FIC) and service order codes 
(SOC) are shown.
	
	An FCC-compliant telephone cord and modular plug is 
provided with this equipment. This equipment is designed to be 
connected to the telephone network or premises wiring using a 
compatible modular jack which is Part 68 compliant. See installation 
instructions for details. 

3.      The ringer equivalence number (REN) is used to determine the 
quantity of devices which may be connected to the telephone line. 
Excessive REN's on the telephone line may result in the devices not 
ringing in response to an incoming call. In most, but not all areas, the 
sum of the REN's should not exceed five (5.0). To be certain of the 
number of devices that may be connected to the line, as determined by 
the total REN's, contact the telephone company to determine the 
maximum REN for the calling area.

4.      If this equipment causes harm to the telephone network, the 
telephone company will notify you in advance that temporary 
discontinuance of service may be required. But if advance notice isn't 
practical, the telephone company will notify the customer as soon as 
possible. Also, you will be advised of your right to file a complaint with 
the FCC if you believe it is necessary.

5.      The telephone company may make changes in its facilities, 
equipment, operations, or procedures that could affect the operation of 
the equipment. If this happens, the telephone company will provide 
advance notice in order for you to make necessary modifications in 
order to maintain uninterrupted service.

6.      If trouble is experienced with this equipment (the model of 
which is indicated below) please contact Multi-Tech Systems, Inc. at 
the address shown below for details of how to have repairs made. If the 
equipment is causing harm to the telephone network, the telephone 
company may request you remove the equipment from the network until 
the problem is resolved.

7.      No repairs are to be made by you. Repairs are to be made only 
by Multi-Tech Systems or its licensees. Unauthorized repairs void 
registration and warranty.

8.      This equipment cannot be used on public coin service 
provided by the telephone company. Connection to Party Line Service 
is subject to state tariffs. (Contact the state public utility commission, 
public service commission or corporation commission for information.)

9.      If so required, this equipment is hearing-aid compatible.
	
Manufacturer:           Multi-Tech Systems, Inc.                        
Model Number:           MT2834PCS                       
FCC Registration #:     AU7USA-20673-MM-E               
Ringer Equivalence:     0.3B                            
Modular Jack (USOC)     RJ11C or RJ11W (single line)
Service Center in USA:  Multi-Tech Systems Inc.                                                    
			2205 Woodale Drive                                      
			Mounds View, MN 55112                   
			Voice (612) 785-3500/   
			FAX (612) 785-9874

Canadian Limitations Notice

Notice: The Canadian Department of Communications label identifies 
certificated equipment. This certification means that the equipment 
meets certain telecommunications network protective, operational and 
safety requirements. The Department does not guarantee the equipment 
will operate to the user's satisfaction.

Before installing this equipment, users should ensure that it is 
permissible to be connected to the facilities of the local 
telecommunications company. The equipment must also be installed 
using an acceptable method of connection. In some cases, the 
company's inside wiring associated with a single line individual service 
may be extended by means of a certified connector assembly (telephone 
extension cord). The customer should be aware that compliance with 
the above conditions may not prevent degradation of service in some 
situations.

Repairs to certified equipment should be made by an authorized 
Canadian maintenance facility designated by the supplier. Any repairs 
or alterations made by the user to this equipment; or equipment 
malfunctions, may give the telecommunications company cause to 
request the user to disconnect the equipment.

Users should ensure for their own protection that the electrical ground 
connections of the power utility, telephone lines and internal metallic 
water pipe system, if present, are connected together. This precaution 
may be particularly important in rural areas.

The Load Number  (LN) assigned to each terminal device denotes the 
percentage of the total load to be connected to a  telephone  loop which 
is used by the device, to prevent overloading. The termination on a loop 
may consist of any combination of devices subject only to the 
requirement that the total of the Load Numbers of all the devices does 
not exceed 100. The Load Number for this product is 4.

Caution: Users should not attempt to make such connections 
themselves, but should contact the appropriate electric inspection 
authority, or electrician, as appropriate.

This digital apparatus does not exceed the Class A limits for radio noise 
for digital apparatus set out in Department of Communications.

Compliance with BABT Requirements

Approved for connection to telecommunications system specified in the 
instructions for use subject to the conditions set out in them.
Warning: Interconnection directly, or by way of other apparatus, of 
ports marked "SAFETY WARNING see instructions for use" with ports 
marked or not so marked may produce hazardous conditions on the 
network. Advice should be obtained from a competent engineer before 
such a connection is made.Connection of power supply: This apparatus 
is intended for use when powered by Multi-Tech #01006370. Use of 
other power supply units will invalidate any approval given to this 
product if as a result it ceases to comply with BS6301:1989.

European Low Voltage Directive

When correctly installed and maintained, the modem will present no 
hazard to the user. When correctly installed the modem will be 
connected to the PSTN or a PW and to a Data Terminal Equipment 
(DTE), whose modem connections comply with CCITT 
recommendation V28. The DTE connections are therefore taken to be 
safe voltages (less than  30 volts). 

Compliance with BS6305 Clause 6.2, BS6320 Clause 7.2, and 
BABT/SITS/82/005S/D

a.      The modem is suitable for connection to the Public Switched 
Telephone Network (PSTN) provided by British Telecommunications 
pic or Kingston Communications (Hull) pic. Circuit supply by British 
Communications, Mercury Communication, or Hull City Council. Only 
direct exchange lines may be used, not shared service.

b.      The modem is suitable for household, office, and similar 
general indoor use. It is not suitable for use as an extension to a 
payphone.

c.      BT lines supplied must support either loop disconnect or 
multifrequency tone signalling.

d.      REN (Ringer Equivalence Number).
The REN value of a unit is calculated from 3/n where n is the total 
number of units which can be connected in parallel which will still 
cause the standard bell (as defined in BS6305 Appendix D) to ring.
REN values of less than 0.3 cannot be assigned. 
			REN = 1

If a telephone or other device is connected in parallel with the modem, 
the combined REN must not exceed 4. A BT supplied telephone may be 
assumed to have REN of 1.0 unless otherwise noted.

The approval of this modem for connection to the British Telecom 
public switched telephone network is INVALIDATED if the apparatus 
is subject to any modification in any material way not authorized by 
BABT or if it is used with or connected to: 

i.      internal software that has not been formally accepted BABT.

ii.     external control software or external control apparatus which 
cause the operation of the modem associated call set-up equipment to 
contravene the requirements of the standard set out in 
BABT/SITS/82/005S/D.

All apparatus connected to this modem and thereby connected directly 
or indirectly to the British Telecom public switched telephone network 
must be approved apparatus as defined in Section 22 of the British 
Telecommunications Act 1984.

Compliance with BS6789: Section 3.1 and Part 2

a.      The modem is not capable of allowing Auto Call using '999' or 
other PABX emergency numbers.

b.      Modes other than modes 1, 2, or 3 should not be used on the 
BT PSTN. This modem is a mode 1 device.

c.      Users are advised to check the numbers entered during the 
Auto Call set up phase prior to dialing.

d.      The user should not issue any sequence of commands to the 
modem which would cause the modem to exceed the maximum 
allowable pause of 8 seconds from the time the modem goes off hook 
until dialing begins.

e.      For correct operation of the call progress monitor, the power 
has to be properly connected and switched on.

Compliance with BS6328 Part 1 and BABT/SITS/82/01/C (Use on 
Private Circuits)

a.      The modem is not suitable for use on circuits with British 
Telecommunications signaling at a normal frequency of 2280 Hz.

b.      The modem does not require signaling or otherwise employ 
the frequency range dc to 200 Hz.

c.      The modem may be connected directly to a point-to-point two-
wire or four-wire Private Circuit.

d.      The modem does not require dc from the Private Circuit for 
correct operation. The modem may be damaged if connected, in a 
private circuit mode, to a circuit supplying dc current (the maximum 
permissible direct current is zero amps).

e.      The approval of this modem for connection to British Telecom 
Private Speech band circuits is INVALIDATED if the apparatus is 
subjected to any modification in any material way not authorized by 
BABT or if it is used with, or connected to:
	
	i)      internal software that has not been formally accepted 
		by BABT.
	
	ii)     external control software or external control 
		apparatus which cause the operation of the modem or 
		associated call set-up equipment to contravene the 
		requirements of the standard set out in                 
		BABT/SITS/82/01/C.

All apparatus connected to this modem and thereby connected directly 
or indirectly to British Telecom Private Speechboard circuits must be 
approved apparatus as defined in Section 16 of the British 
Telecommunications Act 1981.

Compliance with DTI 83/009

a.      The apparatus is only approved for compatible PBXs. Consult 
the supplier for a  up-to-date list of compatible PBXs.

b.      There is no guarantee of correct working in all circumstances. 
Any difficulties should be referred to Multi-Tech Systems.

c.      If sockets are required for connection to the PBX, use the BT 
post card only if BT owns the wiring to the PBX.

This apparatus has been approved for the use of the following facilities:
* Auto-calling
* Loop disconnect and MF dialing
* Phone number storage and retrieval by a predetermined code
* Operation in the absence of proceed indication
* Automatic storage of last number dialed
* Tone detection-busy
* Auto clear from the originating end
* DTR dialing
* Modem
* PBX timed break register recall                               
* Digital Simultaneous Voice Data Mode ("DSVD")

Any other usage will invalidate the approval of the apparatus if, as a 
result, it then ceases to comply with the standards against which 
approval was granted.                                           
	
Appendix B
Technical Specifications                                        

Your MT2834PCS meets the following specifications: 

Tradename               MultiModemPCS

Model Number            MT2834PCS, MT2834PCS/ISI, MT2834PCSK, 
			MT2834PCSK/ISI, MT2834PCSI (International)

Data Rates (bps)        28,800, 26,400, 24,000, 21,600, 19,200, 16,800, 
			14,400, 12,000, 9600, 4800, 2400, 1200, 0-300
			Fax Rates (bps) 14,400, 9600, 4800

Data Format             Serial, binary, asynchronous at 0-300, 1200, 2400, 
			4800 , 9600, 14,400, 16,800,19,200, 21,600, 24,000, 
			26,400, 28,800 bps; synchronous at 1200, 2400, 
			4800  9600,14,400, 16,800,19,200, 21,600, 24,000,      
			26,400, 28,800 bps

Data Compatibility      ITU-T V.34, CCITT V.42bis, V.42, AT&T 
			V.32terbo, CCITT V.32bis, V.32, V.21*,V.22bis,
			V.22, V.23*, Bell 212A and 103/113 
			(*International models)

Fax Compatibility       CCITT V.17, Group 3, V.29, V.27ter and 
			EIA TR-29 Class 2

Error Correction/       V.42 (LAP-M or MNP 3 & 4),      
Data Compression        V.42bis, (4:1 throughput), MNP 5 (2:1 
			throughput)


Speed Conversion        Serial port data rates adjustable to 300, 
			1200, 2400, 4800, 9600, 19,200, 38,400, 57,600 
			and 115,200 bps

Flow Control            Xon/Xoff, Hardware RTS/CTS, ENQ/ACK, Multi-
			Tech Supervisory Protocol (MSP)

Mode of Operation       Digital Simultaneous Voice Data (DSVD), 
			Fax On-line modes, and "AT" , "AT" Style or 
			V.25bis Command modes -- Full duplex over both 
			dial-up lines and 2-wire leased lines

Intelligent Features    Automatic or manual dialing, Automatic or 
			manual answer, Microprocessor-controlled, remote 
			configuration, EIA extended Automode, adaptive 
			line probing, automatic symbol rate and carrier 
			frquency during start-up, retrain and rate 
			renegotiation, Autodial, Redial, Repeat dial, 
			Dial linking, Tone dial, Dial pauses, Call status 
			display, Auto-parity and data rate selection, 
			Keyboard-controlled modem options, Non-volatile 
			memory and on-screen displays for modem option 
			parameters and up to ten telephone numbers/command 
			lines of up to 60 digits each, TalkAnytime allows 
			users to establish Digital Simultaneous Voice Data 
			Link anytime the telephone handset is picked up, 
			Help menus 

Command Buffer          60 characters

Data Modulation         Trellis Coded Modulation (TCM) at 28,800, 26,400, 
			24,000, 21,600, 19,200, 16,800, 14,400, 12,000 
			and 9600 bps; Quadrature Amplitude Modulation (QAM) 
			at 9600 (non-trellis), 4800 and 2400 bps, PSK at 
			1200 bps, FSK at 300 bps

Fax Modulation          V.17 TCM at 14400, 12000, 9600, and 7200 bps
			V.29 QAM at 9600 and 7200 bps
			V.27ter DPSK at 4800 and 2400 bps
			V.21CH2 FSK at 300 bps (Half Duplex)

Carrier Frequencies Data        

Carrier Frequencies     1800 Hz  V.34/V.32/V.32bis/V.32terbo
			28.8K/26.4K/24K/21.6K/19.2K/16.8K/14.4K/12K/9.6K/
			4.8K

Carrier Frequencies     Transmit Originate:     1200 Hz
2400 & 1200 bps         Transmit Answer:        2400 Hz
(V.22bis/V.22 or        Receive Originate:      2400 Hz
Bell 212A Standard)     Receive Answer: 1200 Hz

Carrier Frequencies,    1270 Hz Mark, 1070 Hz Space for
300 bps                 Transmit Originate
(Bell Standard)         2225 Hz Mark, 2025 Hz Space for
			Receive Originate
			2225 Hz Mark, 2025 Hz Space for                         
			Transmit Answer                                 
			1270 Hz Mark, 1070 Hz Space for                                 
			Receive Answer

Carrier Frequencies     980 Hz Mark, 1180 Hz Space for
V.21                    Transmit Originate                              
			1650 Hz Mark, 1850 Hz Space for                 
			Transmit Answer                                 
			1650 Hz Mark, 1850 Hz Space for                         
			Receive Originate                               
			980 Hz Mark, 1180 Hz Space for                               
			Receive Answer

V.23                    390 Hz Mark, 450 Hz Space for                   
			Transmit Originate                              
			1300 Hz Mark, 2100 Hz Space for                         
			Transmit Answer 
			1300 Hz Mark, 2100 Hz Space for 
			Receive Originate                       
			390 Hz Mark, 450 Hz Space for                   
			Receive Answer

Carrier Frequencies Fax 
	
V.21 CH2                Transmit Originate:  1650 Hz Mark, 1850 Hz Space
(Half Duplex)           Transmit Answer:  1650 Hz Mark, 1850 Hz Space 
			V.27ter Originate/Answer:  1800 Hz
			V.29 QAM        Originate/Answer:  1800 Hz
			V.17 TCM        Originate/Answer:  1800 Hz

Transmit Level          -10dBm (dial-up), 0 dBm (leased-line); dBm level 
			selectable with DIP-Switch #3 in leased line setting; 
			-10dBm (dial-up), 
			-13 dBm (leased-line)* 

Frequency Stability     0.01%

Receiver Sensitivity    -43 dBm under worst-case conditions

AGC Dynamic Range       43 dB

Interface               EIA RS232C/CCITT V.24

Connectors              DB25 (RS232C) connector; Two RJ11 modular 
			phone jack: for line, and telephone set (or two 
			BT plugs--BABT); power jack.

*BABT Only

Diagnostics             Power-on Self Test, Local Analog Loop, Local 
			Digital Loop, Remote Digital Loop.

Indicators              LEDs for Send Data, Receive Data, Carrier Detect, 
			various speed indicators, Off Hook, Terminal Ready, 
			Error Correction, Fax.

Controls                Toggle switches for Voice/Data with Originate and 
			Answer, ON/OFF Switch, DIP-Switches for various 
			modem options

Speaker                 2-inch cone with software- or command-controlled 
			volume.

Operating               0 to 50 C  (32 to 120 F)
Temperature

Power Requirement       115 Volts AC, 60 Hz, .3 amp (2-prong 
			outlet-mounted transformer); 240V/50Hz optional 
			(international)

Dimensions              6.15" x 9.0" x 1.375"				
			15.6 cm x 22.9 cm x 3.5 cm 

Weight                  1.6 pounds/0.72 Kg (without transformer)                
			2.6 pounds/1.18Kg (with transformer)

Limited Warranty        Five years

Appendix C

The Multi-Tech Supervisory Protocol (MSP) is used for 
communication between the MT2834PCS and the PC whenever the 
AT>P1 command has been sent to the MT2834PCS.  MSP is the basis 
of a mode of operation in which packets of information are transmitted 
asynchronously between the PC and modem.  It specifies unique bit 
sequences for voice, data, and "qualified" (control) packet headers, so 
that each of the three are distinguishable from a multiplexed sequence 
of packets.

Modes of Operation

MSP specifies two general modes of operation:  packet mode and 
stream mode.  The active mode of operation is determined by the PC or 
other such device (hereafter referred to as the transmitter) by issuing 
one or more of the following: the modem's recognized Escape 
sequence, one or more AT commands, or a qualified packet.  

Packet Mode

Packet mode allows the multiplexing of diverse packet types into a 
single stream of data.  This relieves the transmitter of having to specify 
a new mode everytime the type of data changes.  This is the default 
condition between the PC and the MT2834PCS immediately after the 
AT>P1 command has been issued to the MT2834PCS.

Note:   The MT2834PCS does not have to enter command mode to 
receive, interpret, or implement commands received in the form of 
qualified packets.

Stream Mode

If the transmitter is setup to send large amounts of one type of packet 
(i.e., voice, data, or qualified information), it may force the receiver 
into stream mode for that particular type of data.  For example, if a file 
transfer has been initiated, then a stream of data packets can be 
expected either from the PC to the modem or visa versa, depending on 
whether the PC is uploading or downloading the file(s).  Putting the 
receiver into stream mode saves the processing requirements of 
identifying each type of packet, because the receiver only needs to scan 
for the <Break> signal within a packet.  All other packets are 
predesignated as a particular type.

Changing Modes of Operation

When the nature of data being transferred changes, the transmitter 
forces the receiver into the appropriate mode (either another type of 
stream mode or packet mode).  To change the mode of operation, the 
modem must be taken out of packet or stream mode, into AT command 
mode, and back into packet mode.

Specifications

The following specifications pertain to the Multi-Tech Supervisory 
Protocol (MSP) as it operates over an asynchronous serial link.

Timing Method:          One 8-bit sync byte heads each packet

Data Format:            Packetized or Streamed

Byte Size:              Eight Bits, No Parity

Packet Structure:       
	Sync            Synchronization Byte (01h) heads all packet 
			types
	ID/LI           Information Byte includes an ID (bit #7) and a 
			Packet-Length Indicator field (01h to 7Fh)*
	Qual            Qualifier Byte (present in Qualified packets only) 
			identifies the nature of the command that follows.
	Data            Data Bytes convey the useful information being 
			transferred.

*       Voice packets are pre-set to 24 or 39  bytes long -- this byte is 
00h in voice packets.  Also, the Length Indicator counts the Qualifier 
Byte in Qualified Packets as one byte.

Field Specifications

The first byte of each MSP packet is a synchronization field (0000 
0001h), which keeps the protocols in step with one another.  The 
second byte of each MSP packet carries two units of information.  The 
seventh bit of this field (the ID bit) identifies the type of packet in 
conjunction with the remaining seven bits (positions 0-6), which 
indicate the number of bytes to follow.  The value of the second field 
maps to the following ranges:

Valid ID/LI Values      
	Voice           00h ONLY
	Data            01h-7Fh
	Qualified       81h-FFh

The third byte in the MSP packet will be the first byte of data if the ID 
indicates any packet other than a Qualified packet.  

If the packet is identified as a Qualified packet (i.e., the second byte of 
the packet has a value between 81h and FFh), the third byte will be a 
Qualifier field, used to indicate the command or parameter contained in 
the packet.  The  recognized values are as follows:

Examples of Packet Structure

Using the descriptions in the Specifications section, this section will 
show examples of the three types of packets.

Data Packet Structure

Voice Packet Structure

Qualified Packet Structure

Appendix D

Tone Dial Frequencies
	
The tone-dialing method combines two frequencies for each of the 
twelve digits found on a Touch Tone dial pad. This method is referred 
to as Dual-Tone Multi-Frequency (DTMF) dialing.  The four horizontal 
rows on a Touch-Tone keypad use the four low frequencies (697, 770, 
852, 941 Hz), while the three vertical columns use the three high 
frequencies (1209, 1336, 1477 Hz). The generally accepted tone 
frequency tolerance is +0.02%.

For example, the digit 4 would be dialed by combining two tone 
frequencies. It would use the frequency 770 Hz from the second row, 
and the frequency 1209 Hz from the first column. In another example, 
the digit 9 would be dialed with the tone frequencies of 852 Hz and 
1477 Hz.

The extended DTMF characters (A, B, C, D) are the high-end 
frequencies (1633 Hz) defined on some telephone sets with a fourth 
vertical column of buttons. This fourth column provides for extended 
PBX control functions; the actual functions provided are dependent on 
the PBX manaufacturer's implementation and feature set.
