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C   Loopback Tests

91

Appendix C: Loopback Tests

Introduction

Each time you turn on your modem, it performs an automatic self-test to ensure
proper operation. Your modem also has three diagnostic tests: local analog loop-
back, remote digital loopback, and local digital loopback. These ITU-T V.54 loop-
back tests isolate telephone circuit and transmission problems.

In a loopback test, data from your computer loops through the circuits of your mo-
dem and/or a remote modem before it appears on your monitor. When the loop has
been completed, the data on your PC’s monitor should match the original data.

The local analog loopback test allows you to verify that the modem’s transmitter
and receiver circuits are functioning properly.

The local digital loopback allows you to verify that the local computer or terminal,
the two modems, and the transmission line between them are functioning properly.

The remote digital loopback test allows you to verify that the remote computer or
terminal, the remote modem, the serial ports, the telephone line, and the local mo-
dem are functioning properly.

Note

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

Local Analog Loopback Test (V.54 Loop 3)

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

Computer or Terminal

Digital

Analog

AT&T1

CONNECT

UUUUUUUUUUUU

Local MultiModem

Figure C-1. Local analog loopback test.

Test procedure

1. Connect the modem to your computer. Using your communication program, set

the desired baud rate and go into terminal mode.

2. Type AT and press E

NTER

; you should get an OK message. Type AT\N and

press E

NTER

 to disable error correction.

Содержание MT5600BA

Страница 1: ...Model MT5600BA Model MT5600BL Data Fax Modem User Guide...

Страница 2: ...ech Systems Inc Adobe and Acrobat are trademarks of Adobe Systems Incorporated IBM is a trademark of International Business Machines Corporation MNP and Microcom Network Protocol are trademarks of Mic...

Страница 3: ...r more of the following measures Reorient or relocate the receiving antenna Increase the separation between the equipment and receiver Plug the equipment into an outlet on a circuit different from tha...

Страница 4: ...Install the Modem in Windows 9 Adding the Modem to Windows 9 Removing Your Old Modem from Windows 9 Step 3 Install and Configure Your Software 10 Step 4 Call the Multi Tech BBS 11 Trio DataComm 11 Wi...

Страница 5: ...62 Assigning Callback Passwords 63 Assigning Callback Phone Numbers 64 Calling Procedure 65 Callback Security Commands 65 Chapter 7 Leased Line Operation Introduction 70 Two Wire Setup 70 Four Wire Se...

Страница 6: ...e and Technical Support Limited Warranty 96 Service 96 Technical Support 97 Online Warranty Registration 97 The Multi Tech BBS 97 To Log on to the Multi Tech BBS 97 To Download a File 97 About the Int...

Страница 7: ...Contents vii Appendix G ASCII Character Map 106 Index 107...

Страница 8: ...MultiModemII User Guide viii...

Страница 9: ...1 Introduction...

Страница 10: ...f two client mo dems connected to each other the maximum leased line data rate is 33 6K bps The MultiModemII offers interactive automatic dialing You can store four command lines or telephone numbers...

Страница 11: ...synchronous and asynchronous data transfer Both models support two wire leased line operation The BL model also supports four wire leased line operation with dial backup and leased line restoral Suppo...

Страница 12: ...disk A CD containing Trio data and fax software If any of these items are missing please contact Multi Tech Systems or your dealer dis tributor see Appendix D for information on contacting Multi Tech...

Страница 13: ...2 Quick Start...

Страница 14: ...or to match your computer s serial port on the other end 4 A nearby AC power outlet 4 A nearby telephone line jack 4 A nearby leased line jack or terminals optional Safety Warnings Use this product on...

Страница 15: ...e oth er end into a serial port connector on your computer such as COM1 or COM2 Dialup Connection Plug one end of the modular phone cable into the modem s LINE jack and the other end into a public swi...

Страница 16: ...r supplied with the modem Use of any other trans former voids the warranty and can damage the modem Surge Protectors and Lightning Power surges and other transient voltages on power lines such as thos...

Страница 17: ...to install the modem After the modem is installed click Finish to exit 5 If Windows cannot identify your modem for instance if it identifies your mo dem as a Standard Modem click Change A dialog box w...

Страница 18: ...d S0 0 to the string To use Caller ID with the modem add S0 2 to the string Caller ID infor mation is sent between the first and second rings so the phone must ring at least twice befor the modem pick...

Страница 19: ...ech BBS You can test the modem s data functions by calling the Multi Tech bulletin board system BBS and downloading REGISTER DOC if you have Microsoft Word 6 0 or later or REGISTER TXT if you do not T...

Страница 20: ...2432 in the Phone number box Local and international users type 612 in the Area code box and 785 3702 in the Phone number box 5 Verify that your modem is selected in the Connect using box then click...

Страница 21: ...ude the comma 3 Click File then click Save and save as multibbs trm 4 Click Phone then click Dial to dial the BBS You will know you have reached a modem by the harsh sounds of the modem handshake 5 Wh...

Страница 22: ...tems in the Company box and 612 785 9874 in the Number box 6 Click Next Dialog 7 Select a cover sheet and then click Next Dialog 8 Type a cover sheet message and then click Next Dialog A preview windo...

Страница 23: ...click Finish 12 Microsoft Fax opens the registration file in Word or NotePad prints it to the ren dering system then dials the recipient and sends the fax 13 Exit Microsoft Fax when the Status dialog...

Страница 24: ...MultiModemII User Guide 16...

Страница 25: ...3 Using the Front Panel...

Страница 26: ...up your communication program You also can configure your modem either through the front panel or by sending AT commands to the modem This chapter describes how to configure it using the front panel...

Страница 27: ...acter press the and buttons To go to the next character position press the button To backspace press the button before selecting a character To exit without saving press the button several times To sa...

Страница 28: ...MultiModemII User Guide 20 Trunks Limbs Branches Twigs Menu Overview...

Страница 29: ...t operating status of the modem Limb changes are automatic but certain options can be accessed by pressing the button Note that when the modem is online pressing the button shows the connect status in...

Страница 30: ...configure the modem s basic operating conditions When entering a number use the and buttons to scroll through a list of digits and characters To go to the next position press the button To back up or...

Страница 31: ...Trunk to configure RS 232 dial backup and callback se curity options When entering a number or password use the and buttons to select a character or digit To go to the next position press the button T...

Страница 32: ...assword When entering the password use the and buttons to scroll through the alphabet To go to the next character po sition press the button To backspace or to exit press the button several times Limb...

Страница 33: ...to store list and dial these numbers When entering a number use the and buttons to scroll through the available digits and dialing commands To go to the next position press the button To backspace or...

Страница 34: ...temporarily place the modem in originate mode for back to back testing MANUAL ANSWER Places the modem in answer mode for the time specified by register S7 You can use this option to tempo rarily place...

Страница 35: ...lect blind dialing in which the modem sends the OK CON NECT RING NO CARRIER ERROR and NO ANSWER messag es to the computer and does not look for a dial tone or busy signal or smart dialing in which the...

Страница 36: ...mented RESET FACTORY DEFAULTS Use the and Enter buttons to reset Profile 0 and the modem s active configuration to the factory defaults Same as the AT F W command string Advanced Options RS232 OPTIONS...

Страница 37: ...as the DB0 and DB1 commands For more information about callback security see Chapter 6 Callback Security PASSWORD SETUP Use to enter callback security passwords in memory locations 1 30 Each password...

Страница 38: ...p to four phone numbers can be stored The number in memory location 3 is used for DTR dialing if DTR dialing is enabled LIST PHONE NUMBERS Press the button several times to display the phone number st...

Страница 39: ...4 AT Commands S Registers Result Codes...

Страница 40: ...commands automatically Fortunately communications programs make daily operation of modems effortless by hiding the commands from the user Most users therefore need to use AT commands only when reconf...

Страница 41: ...phone number and dial modifiers Default none Description Dials telephone number s where s may up to 40 characters long and include the following dial string modifiers Spaces parentheses and hyphens ar...

Страница 42: ...to the terminal Command Hn Hook Control Values n 0 or 1 Default 0 Description H0 Go on hook hang up and terminate any T test that is in progress H1 Go off hook make the phone line busy and enter comm...

Страница 43: ...nables automode The modem attempts a handshake at the speed set by S37 or if S37 0 at the highest possible speed During the handshake fallback to a lower speed can occur Note Setting the N command aut...

Страница 44: ...play it in 3 digit decimal format E g S2 gives the response 043 If the short form AT is used the last accessed S register is read Command T Tone Dialing Values P T Default T Description Forces DTMF to...

Страница 45: ...nnect Values n 0 or 1 Default 0 Description Y0 Disables sending or responding to a long space break signal on disconnect Y1 Enables long space disconnect In non error correction mode the modem sends a...

Страница 46: ...odem to hang up Autoan swer is inhibited D2 Q0 Q6 DTR drop causes the modem to hang up Autoan swer is inhibited D3 Q0 Q1 Q4 Q5 Q6 DTR drop causes the modem to perform a soft reset as if the Z command...

Страница 47: ...ns Mode Values n 0 3 Default 0 Description This command determines the DTR operating mode The mo dem treats the M command as a subset of the Q command M0 Selects direct asynchronous operation Note tha...

Страница 48: ...h speed buffering and no error correction Same as N0 Command Rn Clear to Send CTS Control Values n 0 or 1 Default 1 Description R0 Let the CTS state follow the RTS state when online R1 Force CTS high...

Страница 49: ...t None Description Displays statistics for the last connection Command Wn Store Current Configuration Values n 0 or 1 Default None Description W0 Stores current modem settings in nonvolatile memory as...

Страница 50: ...gotiation The modem can only perform data compression on an error corrected link C0 Disables data compression C1 Enables MNP 5 data compression negotiation C2 Enables V 42bis data compression negotiat...

Страница 51: ...3 Default 1 Description A0 64 character maximum block size A1 128 character maximum block size A2 192 character maximum block size A3 256 character maximum block size Command Bn Transmit Break Values...

Страница 52: ...ion and then an MNP connection Failure to make a reliable connection results in the modem hanging up Forces Q5 S36 4 and S48 7 N3 V 42 MNP auto reliable mode The modem attempts first to connect in V 4...

Страница 53: ...e values list of supported max_RX_rate values list of supported x_law values list of supported reserved values list of supported max_TX_rate values Example 0 1 2 3 9 10 11 56 64 69 0 1 300 33600 300 5...

Страница 54: ...x_law An optional number that specifies the PCM code type for 56K modulation The options are 0 Law used in North America and Japan default 1 A Law used outside North America and Japan The modem automa...

Страница 55: ...dence detection criteria are shown in the following table Distinctive ring type 1 2 3 Ring cadence detection criteria 2 0 sec on 4 0 sec off 0 8 sec on 0 4 sec off 0 8 sec on 0 4 sec off 0 4 sec on 0...

Страница 56: ...ck dialing and DTR dialing become unavailable and are replaced by callback security memory locations 1 30 The phone num ber memory locations and their contents are restored when callback security is d...

Страница 57: ...sable backspace S6 seconds 2 255 2 Sets the time the modem waits after it goes off hook before it begins to dial the phone number S7 seconds 1 255 50 Sets the time the modem waits for a carrier signal...

Страница 58: ...one or serial port activity before it enters low power sleep mode The timer is reset upon any serial port or telephone line activity S25 10 ms 0 255 5 Sets the length of time that the modem async igno...

Страница 59: ...value attempts an automode connection If N0 is active connection is attempted at the most recently sensed serial port speed MS command settings are updated to the appropriate values If N1 is active c...

Страница 60: ...at contributes to a NO CARRIER message Use the S86 command to read the value 0 Normal disconnect no error occurred 4 Loss of carrier 5 V 42 negotiation failed to detect an error correction modem at th...

Страница 61: ...at 115200 bps 20 CONNECT 230400 Connected at 230400 bps 22 CONNECT 75TX 1200RX V 23 connection in originate mode 23 CONNECT 1200TX 75RX V 23 connection in answer mode 24 DELAYED Delay is in effect fo...

Страница 62: ...rrier detected 159 CARRIER 50000 50000 bps data carrier detected 160 CARRIER 52000 52000 bps data carrier detected 161 CARRIER 54000 54000 bps data carrier detected 162 CARRIER 56000 56000 bps data ca...

Страница 63: ...nnected at 45333 bps V 90 189 CARRIER 45333 45333 bps data carrier detected V 90 190 CONNECT 46667 Connected at 46667 bps V 90 190 CARRIER 46667 46667 bps data carrier detected V 90 191 CONNECT 49333...

Страница 64: ...MultiModemII User Guide 56...

Страница 65: ...5 Remote Configuration...

Страница 66: ...ord is incorrect the word CONNECT appears and the local modem is returned to online mode If the password is correct an AT_ command prompt appears 4 Type AT commands to configure the remote modem It is...

Страница 67: ...an change a remote modem s remote configuration es cape character The remote configuration escape character is stored in register S13 The factory default is 42 which is the ASCII code for the asterisk...

Страница 68: ...MultiModemII User Guide 60...

Страница 69: ...6 Callback Security...

Страница 70: ...n a separate operation also assign phone number 6127853000 to memory location 16 when the modem receives the password APRICOT it calls phone number 6127853000 Because there is no way to examine the pa...

Страница 71: ...rd for the first callback memory location type AT CBP01 xxxxxxxxxx where xxxxxxxxxx is the first password and press ENTER The password must be six to ten characters in length 3 To store a callback pas...

Страница 72: ...e AT CBN01 9 16127853000 3 To store a callback phone number in the second memory location type AT CBN02 xxxxxxxxxx where xxxxxxxxxx is the dialing string and press ENTER Note that the memory location...

Страница 73: ...ted 4 If the password is valid the callback modem disconnects Then after a short delay it calls the number associated with the password and establishes a work ing connection Callback Security Commands...

Страница 74: ...r Guide 66 Command CBPy x Store Callback Password Values y 01 30 x password 6 10 characters Defaults None Description Stores callback security password x in memory location y The password must have 6...

Страница 75: ...6 Callback Security 67 Callback Assignments Location Password Phone number 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30...

Страница 76: ...MultiModemII User Guide 68...

Страница 77: ...7 Leased Line Operation...

Страница 78: ...MT5600BL modem connect the provided modular telephone cable to the LEASED jack Connect the other end of the cable to the two wire leased line jack or terminals supplied by the telephone company 2 Turn...

Страница 79: ...to the SYNC ASYNC OPTIONS screen 6 Press The 4 WIRE LEASE ORIG screen appears 7 Choose one of two actions To set up the modem as the originate modem press the Enter button To set up the modem as the...

Страница 80: ...he leased line is still down The restore timer register S15 determines how frequently restoral attempts occur when the modems are in dial backup mode S15 can be set from 10 to 255 minutes in one minut...

Страница 81: ...ess the Enter button to go to the TIME TO RESTORE S15 screen 13 To change the default dial backup time press The ENTER TIME IN MINUTES screen appears 14 Repeat steps 9 and 10 until you have entered a...

Страница 82: ...MultiModemII User Guide 74...

Страница 83: ...8 Solving Problems...

Страница 84: ...When you turn on the modem the LED indicators on the front panel should flash briefly as the modem runs a self test and the liquid crystal display LCD should light If the LEDs and LCD remain off the...

Страница 85: ...hysical port the mo dem is connected to The serial cable might be plugged into the wrong connector check your computer documentation to make sure Or you might have selected a COM port in your software...

Страница 86: ...device refer to the device s docu mentation 4 The serial port might be defective If you have another serial port install the mo dem on it change the COM port setting in your software and try again 4...

Страница 87: ...ion was made You might have dialed a wrong number and a per son answered instead of a computer or you might have dialed the correct number but the other computer or software was turned off or faulty C...

Страница 88: ...river COMM DRV to take full advantage of the UART s speed 4 If you are using a slow transfer protocol such as Xmodem try Zmodem or Ymodem G instead 4 Is your line noisy If there is static on your line...

Страница 89: ...ght be set to different word lengths stop bits or parities If you have connected at 8 N 1 try changing to 7 E 1 or vice versa using your communication software 4 You might be experiencing line noise E...

Страница 90: ...me Under DOS or Windows 3 1x you can run either your fax software or your datacomm software but not both at the same time unless you have a special communication device management application In Windo...

Страница 91: ...Appendixes...

Страница 92: ...e line as determined by the total RENs contact the local telephone company 5 If this equipment causes harm to the telephone network the telephone company will notify you in advance that temporary disc...

Страница 93: ...send any mes sage unless such message clearly contains the following information Date and time the message is sent Identification of the business or other entity or other individual sending the messag...

Страница 94: ...ons 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 protect...

Страница 95: ...ective 98 13 EEC of 12 March 1998 on the approximation of the laws of Member States concerning telecommunications terminal and Satellite earth station equipment New Zealand Telecom Warning Notice Use...

Страница 96: ...TR29 2 Error Correction ITU T V 42 LAP M or MNP 3 and 4 Data Compression ITU T V 42bis 4 1 throughput MNP 5 2 1 throughput Speed Conversion Serial port data rates adjustable to 300 1200 2400 4800 9600...

Страница 97: ...smit originate 390 Hz mark ITU T V 23 450 Hz space 1200 bps Receive originate 1300 Hz mark 2100 Hz space Transmit answer 1300 Hz mark 2100 Hz space Receive answer 390 Hz mark 450 Hz space Carrier Freq...

Страница 98: ...nce Diagnostics Power on self test local analog loop local digital loop re mote digital loop Indicators 32 character backlit LCD for status and configuration infor mation LEDs for Transmit Data Receiv...

Страница 99: ...the two modems and the transmission line between them are functioning properly The remote digital loopback test allows you to verify that the remote computer or terminal the remote modem the serial p...

Страница 100: ...omputer 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 Note You can also start and stop an analog loopback test by using...

Страница 101: ...an OK mes sage If you wish to stay on line with the remote modem for normal data trans mission type AT T and press ENTER to exit the test then type ATO and press ENTER to return on line If you wish to...

Страница 102: ...test by using the front panel LCD and buttons See Diagnostic Options Trunk in Chapter 3 Back to Back Test This test verifies proper operation by connecting two MT5600BLs back to back using an RJ 11 ca...

Страница 103: ...is converted to digital data is reconverted into analog and then is transmitted back to your modem Your modem passes this test if the data received on your monitor is the same as the data entered fro...

Страница 104: ...onsistent with MTS s instructions MTS s entire obligation under this warranty shall be limited at MTS s option to repair or replacement of any products that prove to be defective within the warranty p...

Страница 105: ...solving tips The phone number for the Multi Tech BBS is 800 392 2432 USA and Canada or 612 785 3702 international and local The BBS can be accessed by any asynchronous modem operating at 1200 bps to 3...

Страница 106: ...s Enter C to go forward in the file list and P to go back 4 To mark one or more files for download type M press ENTER type the list num bers of the files and then press ENTER again 5 Enter D to see a...

Страница 107: ...alley Cottage NY 10989 Phone 800 826 0279 Fax 914 267 2420 Email info thesupplynet com Internet http www thesupplynet com SupplyNet Online Ordering Instructions 1 Browse to http www thesupplynet com I...

Страница 108: ...f the firmware at the Multi Tech Web site or BBS If your modem already has the current firmware there is no need to update it 3 Download the upgrade file for your modem 4 Extract the upgrade files fro...

Страница 109: ...already be configured for the Multi Tech BBS 2 When the BBS welcome screen appears type your first name last name and password following the prompts If you are a first time caller the BBS asks if you...

Страница 110: ...progress of the download 7 To log off the BBS press ENTER type G for good bye and then press ENTER twice more Step 4 Extract the Upgrade Files 1 Move the downloaded upgrade file to a temporary directo...

Страница 111: ...end Text File dialog box find the temporary directory or folder in which you unarchived the upgrade file select All files in the Files of type box and double click the name of the boot code file e g 2...

Страница 112: ...TD DTE DB 25 connector DCE DB 25 connector DTR 20 RI 22 CD 8 GND 7 DSR 6 CTS 5 RTS 4 RD 3 TD 2 Figure F 1 25 pin to 25 pin RS 232 cable 20 DTR 22 RI 8 CD 7 GND 6 DSR 5 CTS 4 RTS 3 RD 2 TD DCE DB 25 co...

Страница 113: ...n connector DCE DB 25 connector Figure F 3 Macintosh cable Leased Line Pinouts RJ 11 Modular Plug To Terminal Block Screws 2345 2 3 4 5 Red Tip Green Ring Figure F 4 Two wire leased line cable RJ 11 M...

Страница 114: ...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...

Страница 115: ...Index...

Страница 116: ...regulations 86 carriage return character 49 carrier loss disconnect time setting 49 CD Carrier Detect AT command 37 indicator 92 menu options 23 28 cellular operation 46 Clear to Send command 40 COMM...

Страница 117: ...opback test 30 93 95 Long Space Disconnect command 37 loopback tests 24 30 91 95 lost data 81 M Macintosh cable pinouts 105 menu system 19 30 messages 53 55 Microsoft Fax 15 MNP 5 data compression 3 4...

Страница 118: ...9 S01 49 S02 49 S03 49 S04 49 S05 49 S06 49 S07 49 S08 49 S09 49 S10 49 S11 49 S12 49 S13 50 59 S14 39 S15 29 50 72 73 S17 29 50 72 73 S18 40 50 S24 50 S25 39 S26 50 S29 50 S30 50 S32 50 S33 50 S35 50...

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