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PN 88300150

4/3/01

42

S18

Automatic Leased Line Restoral

Unit: 1 min.

Range: 10-255 min.

Default: 30 min.

Description: When the MT2834MR is in the dial back-up mode of operation, it will periodically check the

leased line to see if it’s operational and try to restore the leased line if possible. The
frequency of restoral attempts is defined by the contents of S-Register S18.  

The default for S18 is 30 minutes and can be set in one minute increments from 10 to 255
minutes. Setting the restoral frequency to a value less than 10 minutes causes excessive
breaks in the dial-up operation.

S19

Dial-Back Timer

Unit: 1 min.

Range: 0-255 min.

Default: 1 min.

Description: S19 is a timer that starts when the leased line goes down and the modem has determined

that the line is bad.  When the set time is reached, the originate modem dials the answering
modem.  The answering modem uses this same timer to determine when it will accept the
ring.

S24

PBX/CBX Disconnect Drop Time for DSR/CTS/CD

Unit: 50 mSec.

Range: 0-255

Default: 20

Description: Some PBX and CBX phone systems require the modem’s DSR, CTS, and/or CD signals to

behave in a certain manner when calls are disconnected. The MT2834MR’s &R&S, and
&C commands cause the modem to drop these signals for a specified time period upon
disconnect, and then bring the signal(s) up again.

S24 defines the length of time that the signals drop. The default setting of 20 results in a
one second drop time, which is what most PBX/CBX systems with this requirement need.

S25

DTR Dropout Time

Unit: 100 mSec.

Range: 0, 1 through 255

Default: 0

Description: S25 defines the amount of time that DTR must be dropped before the modem disconnects.

Normally, a disconnect occurs when DTR is dropped for 50 milliseconds or more.

The S25 unit value for zero is the default value of 50 mSec. For values from 1 through 255,
the unit value is 100 mSec.

Содержание MT2834MR

Страница 1: ...PN 88300150 4 3 01 1 MT2834MR MT2834MRI and MT2834MRK Owner s Manual ...

Страница 2: ... 4 3 01 Manual revised and reformatted for distribution on diskette TRADEMARKS Trademarks of Multi Tech Systems Inc are as follows MultiModem MultiModemII MultiModemManager MultiExpress MultiExpressFax Multi Tech and the Multi Tech logo MNP and Microcom Network Protocol are trademarks of Microcom Inc AS 400 and System 3x is a trademark of IBM Macintosh is a trademark of Apple Computer Inc Unix is ...

Страница 3: ...6 CHAPTER 3 COMMAND MODE OPERATION 3 1 Introduction 18 3 2 Typographic Conventions Used in This Manual 18 3 3 Functional Modes 19 3 4 AT Commands 21 3 5 Result Codes 24 3 6 Command Mode Fundamentals 26 3 7 Dialing Commands 32 3 8 Immediate Action Commands 34 3 9 Configuration Commands 36 CHAPTER 4 S REGISTERS 4 1 Introduction 38 4 2 Reading and Assigning S Register Values 38 4 3 AT Commands that A...

Страница 4: ...R 7 DIP SWITCHES AND JUMPERS 7 1 Introduction 64 7 2 16 Position DIP Switches 65 7 3 16 Position DIP Switch Settings 68 7 4 Jumper Settings 70 CHAPTER 8 SERVICE WARRANTY TECH SUPPORT 8 1 Introduction 72 8 2 Limited Warranty 72 8 3 Tech Support 72 8 4 Service 72 8 7 How to Find Multi Tech on the Internet 73 8 9 Upgrading the MT2834MR Firmware 73 APPENDICES Appendix A ASCII Codes Hex Decimal Convers...

Страница 5: ...ntained in each chapter and appendix is as follows Chapter 1 Introduction Description This chapter begins with a short introduction followed by a guide which you are now reading to the use of the manual We then provide a more detailed description of the modem as well as a chart containing the modem s technical specifications This is then followed by sections covering power LED indicators and a bri...

Страница 6: ...rd can be configured independently from each other via the MultiCommManager Model MR4800 The rack can support and control up to 16 MultiModem cards to a total of 48 modems per rack Up to 254 racks can be networked for a total of 12 192 modems on the network under control of a single PC Refer to your MultiCommManager Owner s Manual for more information on the rack and its components Perhaps the mos...

Страница 7: ...writing of the temporary disconnect or change in service give you the opportunity to make changes allowing uninterrupted service and inform you of your rights to bring a complaint to the FCC 1 4 1 FCC Fax Update The Telephone Consumer Protection Act of 1991 makes it unlawful for any person to use a computer or other electronic device to send any message via a telephone fax machine unless such mess...

Страница 8: ...ation V28 The DTE connections are therefore taken to be safe voltages less than 30 volts Approved for connection to telecommunications system specified in the instructions for use subject to the conditions set out in them Approval no NS 3422 23 N 603030 Model MT2834MRK 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 S...

Страница 9: ...oy the frequency range dc to 200Hz 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 private circuit mode to a circuit supplying dc current the maximum permissible direct current is zero amps e The approval of this modem for connectio...

Страница 10: ...0 16 800 19 200 21 600 24 000 26 400 28 800 31 200 or 33 600 bps Configuration Each of the card s 3 modems are independently configurable Compatibility ITU T V 42 V 42bis V 34 AT T V 32terbo ITU T V 32 V 32bis V 25bis V 21 V 22bis V 22 V 23 V 17 Bell 212A and 103 113 Error Correction MNP Classes 3 4 and LAPM Data Compression MNP 5 and V 42bis Speed Conversion Serial port data rates adjustable to 3...

Страница 11: ...dard 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 Tran...

Страница 12: ...chnology on Multi Tech s web site Indicators LEDs for Transmit Data Receive Data Carrier Detect 28 800 bps 24 000 bps 19 200 bps 14 400 bps 9600 bps 2400 bps Off Hook Data Terminal Ready Test and Out Of Service Fax and Error Correction Controls Toggle switches for Busy DIP Switches for various modem options Operating 0o to 50o 32o to 120o F Temperature Power 5 Volts DC at 0 95 Amp Requirements 16 ...

Страница 13: ...the modem is permitted to answer an incoming call When it goes off a connected modem will disconnect The state of this LED matches that of the DTR circuit on Pin 20 of the RS232C interface 12 Error Correction V 42 This LED lights when the modem is in error correction mode and flashes on and off when data compression is enabled 13 Fax FAX This LED lights when the modem is in Fax mode 14 Test Mode T...

Страница 14: ...s 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 This product is intended to be hard wired to the network The final connection to the network is the responsibility of the public telecommunications network operator or a person authorized by that operator Any other apparat...

Страница 15: ...nd mode you may either return to the On Line by typing ATO or terminate the call with the H command Typing ATH will hang up the line bring it on hook bringing the modem out of the On Line mode So the command to hang up a call is three plus signs and then ATH 3 Loss of Carrier After a data connection has been established the modem will disconnect if a loss of carrier occurs for 700 milliseconds 7 s...

Страница 16: ...r functional capabilities using modulated calling and answering tones First the Calling Menu CM a data sequence using V 21 low band modulation a handshaking technique originally developed for 300 bps modems is sent from the originating V 34 modem to the answering V 34 modem This describes the range of functional capabilities the originating modem supports The answering V 34 modem responds to the C...

Страница 17: ...es on the called modem will start a 45 second timer and wait for a carrier signal from the originating modem If carrier is not detected within this period the modem will disconnect hang up and be ready for another call Originate Mode The abort timer will function the same as in the answer mode except that the timer will begin after the modem has completed dialing instead of when it first goes off ...

Страница 18: ...s manual The Carriage Return and Control keys are used in many of the MT2834MR commands Some keyboards label the Carriage Return key as ENTER others use the word ENTER and still others use an arrow pointing down and then left The symbol CR is also commonly used In this manual we symbolize Carriage Return with the word ENTER and will usually use the phrase hit ENTER to instruct you to press the Car...

Страница 19: ...ck Size BAn Baud Adjust Cn Carrier Detect control C Caller ID Detection optional Ds Dial DsDn Store Telephone Number Dn DTR Control Dn DTR Dialing En Echo Commands En Enable Disable Error Correction En Escape Method EBn Asynchronous Word Length En Mode normal auto reliable or reliable En Flow control None CTS or Xon Xoff En Pass through XON XOFF En Enq Ack pacing En Normal mode flow control En Pac...

Страница 20: ...UCP Spoofing T Tone dial T Enable Disable Trellis Coded Modulation Tn Recognise RDL signal U U loop test Vn Verbose or Terse result codes V User control of V 32terbo in Answer Mode W Wait for new dial tone Wn Store configuration in RAM X Extended or basic Result Codes and Call Progress Xn Clock select Yn Long space disconnect Z Zap reset modem Escape to Command Mode when on line Pause in dialing R...

Страница 21: ...acter or too many characters CONNECT 1200 A carrier signal was detected at 1200 bps NO DIALTONE No dial tone was detected and your modem will not dial BUSY A busy signal at the number you dialed was detected NO ANSWER The Remote system did not answer CONNECT 2400 A carrier signal was detected at 2400 bps CONNECT 4800 A carrier signal was detected at 4800 bps CONNECT 9600 A carrier signal was detec...

Страница 22: ...be ATH0 In this example the effect is that the modem hangs up As you become more familiar with the MT2834MR s commands you will find yourself taking advantage of this shortcut 3 6 2 Command Editing You can use the BACKSPACE key on your keyboard to edit characters in the command line The command will not be executed until you hit ENTER The BACKSPACE key erases the previous character for retyping Th...

Страница 23: ... is automatically dialed See Section 3 9 on DTR Dialing D command for details A Continuous Redial not used in MT2834MRK or MT2834MRI If you select the Wait For Dial tone method of dialing see X3 or X4 command it is possible for you to command the MT2834MR to continuously redial maximum 10 redials for DOC units a busy number until your call is answered This is done with the A command This command i...

Страница 24: ...t is the faster method you will probably use tone dialing An example of combining pulse and tone dialing could involve a PBX system where 9 has to be pulse dialed first then the rest of the number tone dialed after pausing for a second dial tone To dial the number type ATDP9 T5551212 and hit ENTER The comma causes a pause which is explained soon P Set Pulse Dial Ratios The P command sets the time ...

Страница 25: ...e modem to flash on hook for a half second just as if you had held the switch hook on a telephone set down for a half second The flash is 90 mSec on the MT2834MRK For example to flash On Hook after dialing the number 555 1234 in order to transfer to Extension 5678 type ATDT5551234 5678 The commas cause a 4 second pause just to be safe Quiet Answer The command causes the MT2834MR to wait before pro...

Страница 26: ...alled linking To link the number at N1 to the number at N2 type ATN1N2 and hit ENTER Several numbers can be linked in the same command For example to link N1 to N2 to N3 to N4 or link N1 to N2 and back to N1 and then back to N2 type ATN1N2N3N4 in the first example and ATN1N2N1N2 in the second example The only limit to the number of numbers that can be linked is the 60 characters allowed in a comma...

Страница 27: ...before and after the plus signs as done in earlier modems BREAK AT CR The MT2834MR provides an alternative Escape method using a Break signal as the Escape Code The Break signal allows the start stop DTE data terminal equipment to signal the modem without loss of character transparency With this method a BREAK signal is used instead of the three plus signs The BREAK is followed by the letters A an...

Страница 28: ...nicating When ATI or ATI0 is typed the MT2834MR responds with 247 When ATI1 is typed the modem responds with a three digit firmware version number L5 L7 Listing Current Operating Parameters The L5 and L7 commands allow you to list the current operating parameters of your modem This information can be very useful when reconfiguring your modem such as when you are changing communications software or...

Страница 29: ...hat the setting of the W command defines the source of the default parameters and values that your modem reads as its factory default settings W Storing Configuration S Register Parameters in the Modem s Non Volatile Memory The MT2834MR can store its configuration parameters and S Register values in its non volatile read write RAM memory Type the W command to store parameters and S Register values...

Страница 30: ...lti Tech responses which include RELIABLE and COMPRESSED responses and a set that more closely matches the Standard AT command set result codes AT Q0 selects Multi Tech responses with Reliable Compression modifiers DIALTONE BUSY NO ANSWER With this setting the terse response for CONNECT 2400 is 9 This is the factory default setting AT Q1 selects Standard AT responses with no Reliable Compression m...

Страница 31: ...ust described and blind dumb dialing where instead of detecting actual dial tones the modem relies on timed pauses When the wait for dial tone method is chosen the busy signal detection capability is also activated The X command is also used to select which dialing method is used Five different X commands are available X0 through X4 with five different effects on the MT2834MR s result code set X0 ...

Страница 32: ...DTR is dropped from On to Off and will also go on hook hang up if it is on line Type AT D0 or AT D to cause the MT2834MR to ignore DTR Type AT D1 to cause the modem to go on hook hang up with loss of DTR The modem enters Command mode when DTR goes high again Auto answer is disabled while DTR is low Type AT D2 to cause the modem to go on hook with loss of DTR The modem enters Command mode when DTR ...

Страница 33: ...standard modem a ITU T V 22 Bell 212A 1200 bps modem or a Bell 103 113 300 bps modem The function of the A command is to detect and select the operational baud rates which the MT2834MR will use for initial handshake and speed selection Note The A command does not control the originating bps rate of the modem that is done by the Modem Baud Rate command MBXXXX but only answer mode fallback speeds Ty...

Страница 34: ...Dialing be sure that 12 Position DIP Switch 1 is in the UP position so that DTR is not forced on Refer to Chapter 7 F Fallback Modes When On Line If the line conditions deteriorate the MT2834MR automatically drops its transmission speed fallback The F command controls the different ways that the MT2834MR falls back During operation if the error rate becomes too great the modem performs a rate nego...

Страница 35: ...dem will ignore the RDL signal Refer to Chapter 6 T Enable Disable Trellis Coded Modulation The T command enables or disables Trellis Coded Modulation for the MT2834MR There is usually no need to disable turn off Trellis Coded Modulation except under an unusual line condition called impulse noise The command AT T0 turns off Trellis Coded Modulation and AT T1 turns it on The factory default setting...

Страница 36: ...ming pin 15 from the Receive Clock pin 17 from the DTE therefore 15 and 17 are the same In Slave mode all timing is controlled by the receive clock The position of pin 3 is insignificant when in Slave mode AS AS 400 Support The MT2834MR has the ability to function in an IBM AS 400 environment The AS1 command enables AS 400 mode and causes the MT2834MR function with the IBM command set The AS0 comm...

Страница 37: ...ctory default setting is C0 Note The C command is not used in the MT2834MRI or the MT2834MRK CD Cleardown at Disconnect The CD command is used for control of cleardown at disconnect in V 32 V 32bis and V 34 modes The CD command enables or disables execution of a cleardown a Cleardown is an ITU standard signal recognized by ITU compatible modems A cleardown should make a disconnect by the remote mo...

Страница 38: ... attempt R1 Ring message and pin 22 enabled on outbound callback attempt The factory default setting is R0 V User Control of V 32terbo in Answer Mode V0 V 32terbo enabled V1 V 32terbo disabled The factory default setting is V1 Note The bits that are used in the rate sequence words for V 32terbo can cause handshaking to fail with some V 32bis modems ...

Страница 39: ...he number of rings that have occurred It is a read type of register and is seldom if ever used in typical operation Each time an incoming ring signal is detected S1 increases its value by one up to a maximum of 255 If you set S1 to a value other than its default value of zero or if the value is increasing with rings this new value remains stored in S1 for eight seconds after the last ring is count...

Страница 40: ...ecuting a dial command The default setting is two seconds Decimal 2 or four seconds S7 Time for Carrier Abort Timer Unit 1 sec Range 1 255 1 45 Default 45 Description S7 defines the Abort Timer lack of carrier delay time The default value is 45 seconds Decimal 45 This means that after dialing the modem waits for a carrier signal for up to 45 seconds and if none is detected aborts the call The maxi...

Страница 41: ... 80 Description S11 sets the speed of tone dialing spacing and tone duration times The default value is 70 units Decimal 70 or 80 units where each unit is one mSec meaning that each tone is on for 70 mSec with a 70 mSec pause between each The minimum S11 value allowed by most telephone systems is 50 mSec 50 units Very few telephone systems can handle anything faster than that The maximum S11 value...

Страница 42: ...e answering modem The answering modem uses this same timer to determine when it will accept the ring S24 PBX CBX Disconnect Drop Time for DSR CTS CD Unit 50 mSec Range 0 255 Default 20 Description Some PBX and CBX phone systems require the modem s DSR CTS and or CD signals to behave in a certain manner when calls are disconnected The MT2834MR s R S and C commands cause the modem to drop these sign...

Страница 43: ...tion S32 sets the time period to validate the escape sequence If the time interval expires before the escape sequence is employed by hitting ENTER the escape sequence is aborted The default is 20 units one second S34 Buffer Length of Command Mode after On line Escape Sequence Unit ASCII Range 0 60 Default 10 Description If the number of characters after AT exceeds the S34 buffer length value the b...

Страница 44: ...and 2 In a second example let s say that you wish to configure the MT2834MR modem to answer incoming calls after the 30th ring instead of after the first ring To configure S Register S0 with a value of 30 type ATS0 30 and hit ENTER 4 2 2 Examples of Reading Values To verify that you entered the value correctly in the above examples type ATS8 and hit ENTER in the first example and ATS0 in the secon...

Страница 45: ...throughput than the modem s modulation speed The throughput increase depends on the type of data transmitted The MT2834MR also supports ITU T Group 3 EIA TR 29 Class 2 fax operation This enables the modem to send and receive text graphics and images to and from any Group 3 fax machine The MT2834MR is set for one of three different modes of operation along with activating data compression in Reliab...

Страница 46: ...ive your terminal or computer must present data to the phone line at a higher speed than which the modem is sending it over the phone line This chapter also covers commands that control error correction turn data compression on and off and others that are related to high performance operation along with the changes in the result codes 5 2 How V 42 Detects and Corrects Errors Some of the better kno...

Страница 47: ...to a lower speed To achieve a data rate which is higher than the modem baud rate use the modem s speed conversion features by turning Baud Adjust off BA0 and operate the serial port at a higher speed than the modem baud rate For example the serial port must be set to 4800 9600 19200 38400 57600 or 115 200 bps SB115200 To use data compression the modem must to be driven at full capacity In other wo...

Страница 48: ...P M error correction and disables MNP This command is for Originate mode only Answer mode still accepts MNP or LAP M 4 L3 Command In the above commands the modems use a two phase process to establish a V 42 connection Detection to establish whether the remote modem is also error correcting and Protocol Establishment to determine parameters and establish the error correction connection If you know ...

Страница 49: ...other Flow control is necessary so that a device does not receive more data than it can handle In the case of the MT2834MR there is a need for flow control in both directions Flow control for data passing from your computer to the modem is called Modem Initiated Flow Control and flow control for data passing from the modem to your computer is called Computer Terminal Initiated Pacing see Figure 5 ...

Страница 50: ...nitiate flow control by issuing Xon Xoff commands or by toggling the CTS signal on the RS232C interface The modem can also be configured to react to similar commands and signals from the computer or terminal to which it is attached via the RS232C interface We refer to computer or terminal initiated flow control as Pacing When the modem is set for Pacing On the modem responds to the terminal or com...

Страница 51: ...stems Doing so does not effect any other flow control or pacing already configured in the modem When configured for ENQ ACK the ENQ CTRL E and ACK CTRL F signals from the HP equipment will be accepted and responded to according to Hewlett Packard protocol 5 13 Compression Error Correction Flow Control Pass Through and Pacing Commands The MT2834MR has a variety of commands to control its error corr...

Страница 52: ...elected 5 14 Error Correction Result Codes When the MT2834MR is operating with error correction enabled five of its responses are altered to let you know that you have made a connection in Reliable mode These Result Codes for a V 42 MNP connection are listed below Verbose Terse CONNECT RELIABLE 1R CONNECT 1200 RELIABLE 5R CONNECT 2400 RELIABLE 9R CONNECT 4800 RELIABLE 11R CONNECT 9600 RELIABLE 12R...

Страница 53: ...400 4800 9600 14 400 19 200 21 600 24 000 26 400 28 800 31 200 or 33 600 bps In this application speed conversion allows the modem to match its speed to that of an in calling modem while at the same time communicating with the attached computer through its RS232C port at a fixed baud rate which can be preselected at 300 1200 2400 4800 9600 19 200 38 400 57 600 or 115 200 bps The flow control and p...

Страница 54: ... to a lower baud rate in an attempt to match the speed of that modem For example if the MT2834MR is set for 33 600 bps and calls another modem that has a top speed of 9600 bps it will drop to 9600 bps To set the Modem Baud Rate type AT MBn where n can be 75 in ITU T V 23 mode 300 1200 2400 4800 9600 14 400 19 200 24 000 28 800 or 33 600 bps as listed below AT MB75 ITU T V 23 AT MB300 300 bps AT MB...

Страница 55: ... during the Auto Reliable time period The factory default setting is A0 BS Maximum Block Size The maximum size of Reliable mode data blocks is controlled with the BS command MNP Class 3 sends blocks of 1 to 64 characters MNP Classes 4 and 5 normally send blocks of 1 to 256 characters Reducing the block size for Classes 4 and 5 to 64 characters may give a smoother flow of data and better throughput...

Страница 56: ...will not abort not matter how many times the same block is resent Type AT R0 to disconnect if the retransmit count is exceeded Type AT R1 to not disconnect due to excessive retransmits The factory default setting is R0 E V 42 Error Correction at 300 bps At 300 bps error correction is not normally used E1 lets the MT2834MR to function in either Normal E0 Auto Reliable E1 or Reliable E2 mode E0 whic...

Страница 57: ...ded Xon Xoff commands can be passed through the modem to a remote computer or terminal The MT2834MR s speed conversion feature allows it to operate at one speed over the telephone lines and another speed at the RS232C serial port This allows the computer or terminal to communicate with the modem at a fixed speed of up to 115 200 bps while the modem operates at various speeds up to 28 800 bps This ...

Страница 58: ... or a remote modem When the loop has been completed the original data entered should match the data received back on your PC s 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 p...

Страница 59: ...essage 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 5 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 mo...

Страница 60: ...et an OK message 3 Dial the remote modem by entering the Dial command and the phone number to establish On line mode 4 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 5 Type ATU3 from the local PC and hit ENTER Once you receive an OK message from your modem if responses are enabled the loc...

Страница 61: ...nto Terminal mode Type AT and hit ENTER you should get an OK message 3 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 to be supplied Figure 6 3 Digital Loopback Test remote automatic 4 Type the Escape Sequence AT CR or BREAK AT CR which brings your modem into Command mode while s...

Страница 62: ...t both modems in Leased Line mode DIP Switch 10 DOWN 5 Set one MT2834MR to Answer enabled DIP Switch 5 UP and the other MT2834MR to Originate enabled DIP Switch 5 DOWN Note it does not matter which modem local remote is set to Answer Originate just so they are set opposite 6 Set DIP Switch 3 UP on both local and remote modems This changes the transmit level to 10dB and this change is necessary to ...

Страница 63: ...U1 command in Asynchronous mode You then compare the test characters multiple upper case U characters in Figure 6 5 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 ...

Страница 64: ...s Mode 6 9 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 as shown in Figure 6 7 This lets you test the local and remote modem s transmit and receive circuits as well as you...

Страница 65: ... can be set to either the UP marked OPEN or Down position The individual switches can easily be set with your fingernail or a pencil tip Note Before changing any DIP Switches on the MT2834MR please consult your MultiCommManager software manual Many of these options can be controlled by the software Each of the 3 pin two position jumpers is used to select options They are also pre set to factory de...

Страница 66: ...he Up marked OPEN or Down position Each of these DIP Switches controls the following functions for its corresponding on board modem 7 3 1 DIP Switches 1 12 Switch 1 Forced DTR DTR Asynchronous Synchronous Mode Leased Line Dial Up The MT2834MR must have a high DTR signal in order to operate This signal is provided to each modem by the terminal or computer to which it is attached through the RS232 V...

Страница 67: ...witch 2 in the UP position to select SDLC mode Place DIP Switch 2 in the DOWN position for BSC mode SDLC Mode Switch 2 UP BSC Mode Switch 2 DOWN Factory Default Setting UP Switch 3 Enable Suppress Responses Q Asynchronous Mode Dial Up In some applications in Asynchronous mode you may want to suppress all responses from the modem Place DIP Switch 3 in the DOWN position to enable result code respons...

Страница 68: ...received then for the ACK to be returned at the remote end is eliminated Place DIP Switch 4 in the DOWN position to enable UUCP spoofing UUCP Spoofing Enabled Switch 4 DOWN UUCP Spoofing Disabled Switch 4 UP Factory Default Setting UP Switch 5 Disable Auto Answer Ans Asynchronous Mode Synchronous Mode Dial Up In some originate only applications you may wish to disable the MT2834MR s automatic answ...

Страница 69: ... Request To Send Forced RTS Asynchronous Synchronous Mode Leased Line Dial Up If your computer or terminal uses RTS CTS protocol normally used in synchronous applications but also if you are using hardware pacing for V 42 error correction or speed conversion you may want to switch RTS to function independent of CTS DIP Switch 7 UP For most applications especially asynchronous Switch 7 should be se...

Страница 70: ...ctory Default Setting DOWN For more information on Result Codes refer to Chapter 3 Switch 11 Internal External Clocking Synchronous Mode Leased Line Dial Up With the MT2834MR in Synchronous Mode the transmit clock can be supplied by the DTE on pin 24 of the RS232C V 24 interface by DIP Switch 11 positioned UP DIP Switch 11 in the DOWN position enables the DCE to control clocking External Clock pin...

Страница 71: ... status CD and DSR normal Switch 15 UP CD and DSR forced On Switch 15 DOWN Factory Default Setting UP Switch 16 2 Wire 4 Wire Leased Line Asynchronous Synchronous Mode Leased Line 2 Wire Leased Line Switch 16 UP 4 Wire Leased Line Switch 16 DOWN Factory Default Setting DOWN 7 4 Jumper Settings The MT2834MR has three two position jumpers one for each modem for OOS and service Each set of OOS jumper...

Страница 72: ...e seen in Figure 7 1 on the right hand side of the board For Modem B BTEST BV54 BTEST BV54 Pin 25 Output OOS Pin 25 Input Test Mode MT2834MR Default MT2834MRI Default 7 4 3 CTEST CV54 Jumper S305 Jumper S305 sets pin 25 of Modem C as input OOS for the default and output Test Mode as the option setting on domestic US modems On international modems Jumper S305 sets pin 25 of Modem C as input OOS for...

Страница 73: ...o MTS s factory transportation prepaid MTS WILL NOT BE LIABLE FOR CONSEQUENTIAL DAMAGES AND UNDER NO CIRCUMSTANCES WILL ITS LIABILITY EXCEED THE PURCHASE PRICE FOR DEFECTIVE PRODUCTS 8 3 Tech Support Multi Tech has an excellent staff of technical support personnel available to help you get the most out of your Multi Tech product If you have any questions about the operation of this unit call 800 9...

Страница 74: ...h com 8 9 Upgrading the MT2834MR Firmware The MT2834MR has a Flash PROM which contains firmware code for the hardware At various times Multi Tech may add enhancements and or fixes to the firmware The flash technology used in the MT2834MR allows these upgrades to be loaded directly into the PROM chip through the modem s serial port 8 9 1 Using FlashPro to Upgrade Modem Firmware 1 Download FLASHPRO ...

Страница 75: ...19 3 33 51 S 53 83 s 73 115 T DC4 14 20 4 34 52 T 54 84 t 74 116 U NAK 15 21 5 35 53 U 55 85 u 75 117 V SYN 16 22 6 36 54 V 56 86 v 76 118 W ETB 17 23 7 37 55 W 57 87 w 77 119 X CAN 18 24 8 38 56 X 58 88 x 78 120 Y EM 19 25 9 39 57 Y 59 89 y 79 121 Z SUB 1A 26 3A 58 Z 5A 90 z 7A 122 ESC 1B 27 3B 59 5B 91 7B 123 FS 1C 28 3C 60 5C 92 7C 124 GS 1D 29 3D 61 5D 93 7D 125 RS 1E 30 3E 62 5E 94 7E 126 US ...

Страница 76: ...he 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 Not applicable in BABT models 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 f...

Страница 77: ...es shown above Note Switch 3 has no effect in leased line mode in the MT2834MRK 4 UP UUCP Spoofing Disabled Down UUCP Spoofing Enabled 5 UP Enable Automatic Answer dial up Down Disable Automatic Answer dial up 5 UP Answer Mode leased line Down Originate Mode leased line 6 UP Max throughput Enabled Down Max throughput Disabled 7 UP RTS dependent on Interface Down RTS forced On at all times 8 UP Dis...

Страница 78: ...ginate Mode leased line 6 UP Slave Clocking Disabled Down Slave Clocking Enabled 7 UP RTS Dependent on interface Down RTS Forced On at all times 8 UP Disable Command Mode Down Enable Command Mode 9 UP No function Down 10 UP Dial Up Operation Down Leased Line Operation 11 UP External Clock Down Internal Clock 12 UP Synchronous Mode Down Asynchronous Mode DIP Switches 13 16 Synchronous and Asynchron...

Страница 79: ...odem has detected carrier at 9600 bps and gone on line 13 CONNECT 14400 Modem has detected carrier at 14400 bps and gone on line 19 CONNECT 19200 Modem has detected carrier at 19200 bps and gone on line 21 CONNECT 21600 Modem has detected carrier at 21600 bps and gone on line 23 CONNECT 1275 Modem is connected in V 23 mode 24 CONNECT 24000 Modem has detected carrier at 24000 bps and gone on line 2...

Страница 80: ... 19L CONNECT 19200 LAPM 21L CONNECT 21600 LAPM 24L CONNECT 24000 LAPM 26L CONNECT 26400 LAPM 28L CONNECT 28800 LAPM Note 1 If the MT2834MR is used with data compression the word COMPRESSED or the letter C is added to the result codes Note 2 If Standard AT Command Set 2400 Result Codes are selected with Q command the following Result Codes change 9 not used 10 CONNECT 2400 Modem has detected carrie...

Страница 81: ...ects S11 1 mSec 1 255 70 Sets time duration of and spacing between tones in tone dialing 80 255 80 S13 ASCII 0 127 37 Defines Remote Configuration Escape Character S17 10 mSec 0 2500 250 mSec Defines length of break time seconds space to PC S18 30 min 10 255 30 Modem monitors leased line to see if it s operational and will try to restore leased line connection S19 1 min 0 255 1 Dial backup timer u...

Страница 82: ...er size B1 means reduced transmit buffer size BSn n 0 or 1 BS0 means maximum transmit block size of 64 characters BS1 means maximum transmit block size of 256 characters BAn n 0 or 1 BA0 means Baud Adjust is off speed conversion is on BA1 means Baud Adjust is on speed conversion is off Cn n 0 1 C0 forces Carrier Detect on 2 or 4 C1 lets Carrier Detect act normally C2 lets Carrier Detect drop S24 t...

Страница 83: ...s F F loads factory default values from ROM F8 loads factory defaults after F F9 loads RAM defaults after F Fn n 0 or 1 F0 means do not fall back to normal connect if CR received F1 means fall back to normal connect if CR received Gn n 0 1 or 2 G0 turns off ITU T guard tones G1 turns on ITU T 550 Hz guard tone G2 turns on ITU T 1800 Hz guard tone Hn n 0 or 1 H0 means Hang Up go on hook H1 means Go...

Страница 84: ...ns Result Codes will be suppressed quiet Q2 means Dumb Answer Mode Qn n 0 or 1 Q0 selects Multi Tech command set Q1 selects AT command set Rn n 0 or 1 R0 means modem will not reverse modes R1 means modem will reverse modes Rn n 0 1 or 2 R0 lets Clear to Send act normally R1 forces Clear to Send on R2 drops for S24 period on disconnect Rn n 0 or 1 R0 disables ring message on callback modem R1 enabl...

Страница 85: ...NNECT 2400 X1 selects Extended Result w CONNECT 1200 CONNECT 2400 X2 selects Standard AT command set NO DIAL TONE X3 selects Standard AT command set with BUSY X4 selects Standard AT command set with NO DIAL TONE and BUSY Xn n o thru 2 X0 Sync internal clocking X1 Sync external clocking X2 Sync slave clocking Xn n 0 or 1 X0 causes one XOFF to be sent until buffer reaches XON level X1 causes one XOF...

Страница 86: ... a CFIFF indication is given The modem in AT command mode responds with NO CARRIER If country regulations require that the Forbidden Numbers list be checked in AT mode then NO CARRIER is the response to a dial attempt in AT mode Numbers are also be put on the Forbidden Numbers list if the Delayed Numbers list is full and a new number fails for the first time In that case the new number is added to...

Страница 87: ...the first ring There is no disconnect message NO CARRIER if a normal connection is made Set Up and Initialization Before you operate your modem in the V 25bis mode you need to make sure it is set up properly various RS232 lines such as DSR and CTS act as specified in the V 25bis standard Set up involves proper DIP Switch settings and soft switches software controlled conditions V 25bis DIP Switche...

Страница 88: ...d Not Allowed Not Allowed AT CR Not Allowed V 25bis Responses Result Codes When in V 25bis mode the AT V1 command executed your modem provides you with several responses which helps you follow the progress of V 25bis operations These are similar to the Result Codes associated with AT Command mode operation The V 25bis responses are in the form of three character mnemonics as listed on the next pag...

Страница 89: ...n one V 25bis command from AT command mode without leaving AT command mode the V 25bis command follows V2 on the command line Clear Number in Memory CLA Command The CLA command clears a specific number in the mm phone number memory by entering CLAmm Change Serial Baud Rate CSP Command The CSP command changes the serial baud rate of your modem by entering CSPsssss where sssss can equal 0300 300 bps...

Страница 90: ...rogress the modem gives a DLC indication The list contains eight numbers When filled the next number failing bumps off the oldest number on the list onto the Forbidden Number list Numbers on the Delayed Number list that succeed in a connect attempt are removed If a certain number of failed attempts occur the number of failed attempts is specified by each country the number is entered into the V 25...

Страница 91: ...ns governing the way operations are handled The purpose of this document is to detail each country s specific regulations that affect operation of V 25bis in Multi Tech modems 1 Italy a Command Indication modifications 1 Phone number indications include status ZPSTTT a Z U D or F for Unrestricted Delayed or Forbidden b P Delay time if delayed c S Number of retries so far d TTT Interdiction time to...

Страница 92: ...between retries 2 After 2 retries to numbers that answer but give no answer tone CFINT the number is put on the forbidden list 3 After 10 retries with busy or no dialtone the number is put on the forbidden list 4 The number remains on the forbidden list forever 5 Delayed and Forbidden Numbers lists are checked when dialing in AT mode If dialing is not possible then NO CARRIER is the response c Aut...

Страница 93: ...in AT command mode If dialing is not possible then No Carrier is the response c Auto Answer behavior 1 Auto Answer in 5 seconds if no DIC 6 Singapore a Command indication modifications 1 Dialing digit means wait for dialtone acts the same as in dialing string b Delay and Forbidden list behavior 1 5 retries without delay 2 2 minute delay between next 4 retries 3 After 9 retries the number is put on...

Страница 94: ... 7K Formorespecificdetails consulttheEIARS232Cstandarditself The following chart lists the EIA RS232C interface pins and circuits present on the MT2834MR s RS232C Interface connector All other pins are unused PIN MULTI TECH EIA SIGNAL ASSIGNMENT DESIGNATION CIRCUIT SOURCE CIRCUIT FUNCTION 1 PG Protective Ground 2 SD BA DTE Transmitted Data 3 RD BB DCE Received Data 4 RTS CA DTE Request to Send 5 C...

Страница 95: ...N indicates that the MT2834MR is in the data mode and is connected to the communications channel This signal is on during analog loop test mode Signal Ground Pin 7 SG AB The SG lead is connected to signal ground of the modem It establishes the common ground reference for all other interface signals Data Carrier Detect Pin 8 CD CF Direction from modem DCD On positive voltage indicates that data car...

Страница 96: ...omatic answer applications A high DTR signal is required by the modem to answer a call A frequently used method is to have the computer turn on DTR in response to RI Ring Indicator which allows the modem to answer Later DTR is turned off at the conclusion of the log off procedure which forces the modem to disconnect enabling it to receive another call In non auto answer applications it is advisabl...

Страница 97: ... Ground 7 8 8 Carrier Detect 8 9 9 Voltage Test 9 12 12 High Speed 12 15 15 Transmit Clock 15 17 17 Receive Clock 17 20 20 Data Terminal Ready 20 22 22 Ring Indicator 22 25 25 Terminal Busy 25 25 pin Male Connector DB25P type 25 pin Female Connector DB25S type on back of modem or CC216 rack Connects to Terminal or Computer RS232 Interface serial port Gender and pin out depends on device Figure I 2...

Страница 98: ...Our in band escape method is AT CR Our out of band escape method is BREAK AT CR A BREAK signal cannot be sent as part of a data file instead it is sent by a direct program command to the UART used by that computer BREAK is defined as either the transmission of binary 0 for a minimum of 10 bits or as a minimum interval of 135 milliseconds as established in the ITU T X 28 standard There are routines...

Страница 99: ...6 The modem escapes to Command mode 7 The modem executes the command setting S0 1 8 The modem returns to On Line mode S Registers and Escape Sequences There are two S Registers that you may set to modify the functioning of your escape sequences The first is S Register S32 which establishes a value for how much time may elapse between the receipt of the beginning of the escape sequence whether BREA...

Страница 100: ...es and also if any of the following occurs 1 An illegal sequence is detected including a A character other than A follows the BREAK b A character other than T follows BREAK A c Two BREAKS are received in succession 2 The command buffer overflows before a CR occurs If you have any questions about the information contained in this document please direct them to Technical Support c o Multi Tech Syste...

Страница 101: ...ou configure modems remotely This means you can configure modems anywhere in your network from one location without having to visit the sites or rely on remote users to follow your instructions With Remote Configuration which is protected by two level security you can downline load new parameters program new V 42 capabilities and implement new features Remote Configuration also makes troubleshooti...

Страница 102: ...le Remote Configuration and change the remote escape character type in a new S Register S13 value Remote Configuration AT Commands The following AT commands are used with the Remote Configuration feature I Modem LOGIN Password The I command lets you select a unique LOGIN password for your modem Once you have selected a LOGIN password for your modem it only responds to that code Your modem is shipp...

Страница 103: ...D Mode 2 Select 1 or 2 With option 1 the modem goes back into Data mode and with option 2 the modem responds with Password 3 Type your SETUP password and if the code is correct the modem responds with OK You can now use any AT commands remotely as if they were entered locally You cannot change the LOGIN password until you enter the proper LOGIN password 4 When you are done typing AT commands and y...

Страница 104: ...PN 88300150 4 3 01 104 Appendix L MT2834MRI PC Board MT2834MRI PCB Top ...

Страница 105: ...PN 88300150 4 3 01 105 MT2834MRI PCB Chassis 2 ...

Страница 106: ...PN 88300150 4 3 01 106 MT2834MRI Labels ...

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