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Data Service Unit

DeskTop T1

GDC   048R154-000-01

Issue 1 - October 1997

Installation and Operation

General DataComm

Summary of Contents for DeskTop T1

Page 1: ...Data Service Unit DeskTop T1 GDC 048R154 000 01 Issue 1 October 1997 Installation and Operation General DataComm...

Page 2: ......

Page 3: ...3 2 Installation Overview 2 1 Unpacking and Handling 2 1 Preoperational Check 2 1 Option Selection 2 2 Timing Options 2 2 Connections 2 13 DTE Interface Port Connection 2 13 Network Connection 2 13 Pr...

Page 4: ...ne Loopback 4 11 Network Local Test 4 13 Network Local Test with QRSS Self Test 4 13 Network Remote Test 4 14 Network Remote Test with QRSS Self Test 4 16 DTE Self Test 4 17 DTE Local Loopback 4 19 DT...

Page 5: ...twork End to End Self Test 4 9 4 5 Network End to End Self Test Front Panel Control 4 9 4 6 Data Path for Network Payload Loopback 4 11 4 7 Data Path for Network Line Loopback 4 12 4 8 Network Line Lo...

Page 6: ...4 24 Tables 1 1 Equipment List 1 4 2 1 Option Application Notes Switchbank S13 CSU Characteristics 2 4 2 2 Option Application Notes Switchbank S14 Network Characteristics 2 6 2 3 Option Application N...

Page 7: ...Unit its features and its options This chapter contains the Equipment List table Chapter 2 Installation provides directions for installing the DSU and configuring it by means of the switchbanks locat...

Page 8: ...e screen This bold font shows specific input that you type at the keyboard This bold italicized font shows variable input that you type at the keyboard Service and Support General DataComm is committe...

Page 9: ...hen a person whose body contains a static buildup touches a computer component The equipment may contain static sensitive devices that are easily damaged so proper handling and grounding are essential...

Page 10: ...telephone company provided jacks or equivalent Connection of this equipment to party lines and coin telephones is prohibited A label on the bottom of the DT T1 enclosure provides the FCC Registration...

Page 11: ...communications 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 sho...

Page 12: ...present are connected together This precaution may be particularly important in rural areas Users should not attempt to make such connections themselves but should contact the appropriate electric ins...

Page 13: ...Allows the linking of FT1 services with traditional Dataphone Digital Service DDS and generic digital services including support for ANSI T1 403 PN 127 loop up loop down codes Supports one ITU T V 35...

Page 14: ...tional T1 FT1 digital carrier facility provided by the Telco or other carrier It performs both the Data Service Unit DSU function of converting the customer s data stream to bipolar format and the Cha...

Page 15: ...educes the T1 bandwidth available for user data by one half but it eliminates restrictions on the content of user data When the DSU is configured to use alternate DS0s it maintains minimum ones densit...

Page 16: ...g DSU network port to the T1 line 10 to 50 foot lengths 10 foot length included with standalone enclosure models 022H024 XXX Interface cable RJ48C plug to 15 pin male DSU network port to the T1 line C...

Page 17: ...ptions for the DSU by means of the hardware switchbanks located on the pc board Unpacking and Handling The DeskTop T1 DSU is shipped in packing material that is enclosed in a corrugated box Inspect th...

Page 18: ...ble options by which you can adapt it to a variety of configurations The most convenient way to set optionsis to usethe VT100 compatibleterminal interface Directions for connecting to the back panel C...

Page 19: ...applicable The flexibility and complexity of the DSU s timing options require detailed explanations Refer to AppendixC for details and applications of the DeskTop T1 DSU timing options Figure 2 1 Posi...

Page 20: ...configured by means of pc board hardware switches Line Framing ESF S13 2 S13 3 Off Off Selects ESF Framing D4 S13 2 S13 3 Off On Selects D4 Framing Unframed S13 2 S13 3 On Off Selects unframed data tr...

Page 21: ...On for au tomatic LBO Set only one switch On Caution Do not enable automatic LBO for both DSUs in a pair connected back to back Do not enable auto matic LBO when the DSU is con nected to a DS1 Interfa...

Page 22: ...Selects compliance with ANSI network performance messages per Bellcore TR TSY 000194 available only with ESF framing TR 54016 S14 2 On Selects compliance with network maintenance messages per PUB 5401...

Page 23: ...n it detects the appropriate inband loopback code Payload S14 5 S14 6 On Off DSU starts or stops a Payload Loop test when it detects the ap propriate inband loopback code Base Rate 64k S14 7 Off Each...

Page 24: ...verted Invert S15 4 On Channel Receive Data inverted DTE Send Data Normal S15 5 Off Channel Transmit Data not inverted Invert S15 5 On Channel Transmit Data inverted DTE Split Timing Disable S15 6 Off...

Page 25: ...f S15 7 8 DTE Test Leads Disable S10 2 Off DTETest Leads LL andRLdisabled Enable S10 2 On DTE Test Leads LL and RL enabled DTE Test Pattern 2047 S10 3 Off Selects 2047 bit Self Test pattern for channe...

Page 26: ...for other settings Selects lowest numbered DS0 in the group that conveys channel data The rest of the DS0s required to support the selected Channel Data Rate follow sequentially after the one selected...

Page 27: ...0 10 Off On Off On Off 616 704 11 Off On Off On On 672 768 12 1 2 Off On On Off Off 728 832 13 Off On On Off On 784 896 14 Off On On On Off 840 960 15 5 8 Off On On On On 896 1024 16 On Off Off Off Of...

Page 28: ...n 4 Off Off On Off Off 5 Off Off On Off On 6 Off Off On On Off 7 Off Off On On On 8 Off On Off Off Off 9 Off On Off Off On 10 Off On Off On Off 11 Off On Off On On 12 Off On On Off Off 13 Off On On Of...

Page 29: ...k T1 line to the DeskTop T1 DSU as described below The Telco continuously monitors the T1 link and the equipment connected to it Notify the Telco before connecting the DeskTop T1 DSU to the network Th...

Page 30: ...installations only a special cable is required for the network connection Use GDC cable P N 022H020 RJ48C to DB15F to connect the network port to the T1 line Function Direction 027H242 X04 022H024 XX...

Page 31: ...If you cannot be sure that the customer equipment is powered by the same ac source as the DSU verify that the potential difference between the grounding circuits of their respective outlets is less th...

Page 32: ...2 16 Installation GDC 048R154 000 Use of a terminal is optional Configuration can be accomplished entirely by means of the hardware switches on the pc card...

Page 33: ...oes the front panel Through the terminal interface you can alter the configuration of the DSU invoke the full range of its diagnostic test functions view the current status of DTE interface signals an...

Page 34: ...BPV Red Network Bipolar Violations indicator ALM Red Alarm indicator TM Red On while DSU is any Test Mode flashes to indicate errors when Self Test pattern generator checker is in use T1 Red LED Swit...

Page 35: ...s the following Main Menu Type the number that corresponds to the function with which you intend to work Configuration The Configuration function presents ascreen of configuration options Each option...

Page 36: ...d field DT T1 Configuration 0 Return to Main Menu Unit is under Software Control 1 Network Framing ESF 2 Network Coding B8ZS 3 Network Line Type DS 1 4 Network Line Buildout Manual 0dB 5 Network ESF M...

Page 37: ...each For more detailed descriptions of the individual option settings and their effects on operation of the DSU you can consult Tables 2 1 through 2 5 in Chapter 2 Installation Table 3 1 DeskTop T1 Co...

Page 38: ...ual 22 5 dB Auto 4 Network Pre Equalization 0 133 ft 4 is Pre Equalization when Line Type is DSX 1 133 266 ft 266 399 ft 399 533 ft 533 655 ft 5 Network ESF Mode ANSI T1 403 TR 54016 6 Network Timing...

Page 39: ...on Consecutive Alternate C DTE CTS Control Forced ON Follow RTS D DTE DCD Control Forced ON Follow OOF E DTE DSR Control Forced ON Follow LOS F DTE Invert Data Normal Invert SD Invert RD Invert SD RD...

Page 40: ...s from the terminal than are available by means of the DSU front panel switches When you perform a test that employs the DSU Self Test pattern generator and checker the results displayed on screen are...

Page 41: ...ine Loopback 5 Start Network Local Test 6 Start Network Local Test with QRSS Self Test 7 Start Network Remote Test 8 Start Network Remote Test with QRSS Self Test 9 Select DTE Self Test Pattern 2047 P...

Page 42: ...tes that the signal is transitioning as opposed to being in a prolonged On DT T1 Diagnostics 0 Return to Main Menu 1 Stop Test1 2 Inject Single Bit Error ST only 3 Reset Counters Current Test Network...

Page 43: ...urn to the Main Menu Figure 3 5 Monitor Screen DT T1 DTE Status1 TXD TRANS RXD TRANS DCD ON TXC TRANS RXC TRANS DSR ON RTS ON CTS ON DTR ON DT T1 Alarm Status2 Major Minor Network OOF INACTIVE Network...

Page 44: ...vel and the type of DTE interface installed in it Figure 3 6 illustrates the What Are You screen When you are done viewing the What Are You screen type 0 to return to the Main Menu Figure 3 6 What Are...

Page 45: ...mote Loopbacks The DSU can also be commanded remotely into tests that involve looping the networks signal back to be checked for errors at the remote site The remote site DSU transmits inband loop cod...

Page 46: ...h ST T1 indi cator controlled by T1 switch must be On Network Payload Loopback Terminal Interface Network Line Loopback Terminal Interface Front Panel Switch LL T1 indi cator controlled by T1 switch m...

Page 47: ...ommunication Line or Line to DSU Connection Problem Pass or Fail Perform Network Local Test with QRSS Self Test at remote DSU Remote DSU or Equipment Problem Pass or Fail Perform Network Local Test at...

Page 48: ...ual tests appear on the following pages Figure 4 2 Diagnostics Selection Screen DT T1 Diagnostics 0 Return to Main Menu 1 Select LL Mode Unilateral1 2 Start Network QRSS Self Test 3 Start Network Payl...

Page 49: ...f you are do ing a Network Line Loopback or a DTE Local Loopback When Unilateral is selected the function creates only one loopback incoming data back onto the T1 line in the case of the network test...

Page 50: ...run Bit Errors is displayed only when the Self Test function is in use it normally displays the number of detected errors it displays NO SYNC if no test pattern is being received during an end to end...

Page 51: ...est1 2 Inject Single Bit Error ST only 3 Reset Counters Current Test Network QRSS Self Test2 Test Status Running3 Test Duration x minutes y seconds Bit Errors 0000 e004 Next Selection 1 displays Resta...

Page 52: ...es the cooperation of an operator at the remote site to initiate the function in the remote DSU observe the results and terminate the function In the Network End to End Self Test two DSUs transmit int...

Page 53: ...ce Network Interface TPG TPC DTE Interface Network Interface TPC TPG DeskTop T1 DSU DeskTop T1 DSU 2 Press ST switch to start Network End to End Self Test Press switch again to end test 1 T1 indicator...

Page 54: ...terface Diagnostic Selection screen this function is selection 3 Start Network Payload Loopback You can command the payload loopback from the terminal interface regardless of how DSU hardware configur...

Page 55: ...on 4 Start Network Line Loopback Figure 4 8 shows the switches and indicators that are involved when you command a Network Line Loopback from the front panel The DSU also establishes a DTE Local Loopb...

Page 56: ...U is optioned for bilateral loopbacks switch S10 4 a DTE Local Loopback is also initiated when Network Line Loopback is commanded Network Line Loopback 2 Press LL switch to start Network Line Loopback...

Page 57: ...he responsibility of the external device that supplies the test signal To initiate the loopback from the Diagnostics Selection screen select 5 Start Network Local Test Figure 4 9 Data Path for Network...

Page 58: ...hes When you initiate a Network Remote Test the DSU transmits a loop up code to the remote unit for approximately five seconds The remote unit responds by engaging either a Line or a Payload loopback...

Page 59: ...re 4 12 Network Remote Test Front Panel Control Network DeskTop T1 DSU DTE Interface Network Interface DTE Interface Network Interface Line Loopback or Payload Loopback as selected by remote DSU confi...

Page 60: ...nected from their DTEs during the test Network Remote Test with a Line loopback tests the line and the network interface at the remote DSU Network Remote Test with a Payload loopback extends the test...

Page 61: ...ted from two selections in the terminal interface Diagnostics Selection menu once by itself and once in combination with a loopback test The Remote Digital Loopback with Self Test is discussed on a la...

Page 62: ...e data it receives matches that which was transmitted The test checks both DSUs and the T1 link To initiate the test from the terminal interface Diagnostics Selection screen select A Start DTE Self Te...

Page 63: ...he external device that supplies the test signal To initiate the loopback from the Diagnostics Selection screen select B Start DTE Local Loopback Figure 4 18 shows the switches and indicators that are...

Page 64: ...n DSU is optioned for bilateral loopbacks switch S10 4 a Network Payload Loopback is also initiated when DTE Local Loopback is commanded DTE Local Loopback 2 Press LL switch to start DTE Local Loopbac...

Page 65: ...Loopback DTE Remote Digital Loopback The data path for the DTE Remote Digital Loopback is illustrated in Figure 4 20 You can command the loopbackby meansof the terminal interface screen the front pan...

Page 66: ...e DTE Test Leads configuration option is enabled switch S10 2 On Figure 4 20 Data Path for DTE Remote Digital Loopback Figure 4 21 DTE Remote Digital Loopback Front Panel Control Network DeskTop T1 DS...

Page 67: ...generates the selected test pattern and transmits it to the remote DSU which loops it back to be checked for errors at the local DSU The DSUs are electronically disconnected from their DTEs during th...

Page 68: ...nd ST switches to start DTE Remote Digital Loopback with Self Test Press switches again to end test 1 T1 indicator must be Off press T1 switch if indicator is On 3 TM ST and RL indicators are On durin...

Page 69: ...kg Environmental Temperature Operating 32 to 122 F 0 to 50 C derate by 1 C 1000 ft above sea level Non operating 40 to 185 F 40 to 85 C Humidity operating 5 to 95 without condensation Altitude Operat...

Page 70: ...e RJ48C modular jack Network transmitter Frequency 1 544 000 bps 50 bps Pulse amplitude with surge protection 2 40 to 3 60 V at 60 F may vary over a cycle of 60 Hz current Unbalance in height of adjac...

Page 71: ...December 1988 Longitudinal balance 35 dB from 50 to 1500 kHz Transmitter Pre equalization 0 to 655 feet of line length Impedance 100 Channel port customer equipment interface One ITU T V 35 compatibl...

Page 72: ...uperframe AT T 54016 Extended Superframe ESF ANSI T1 403 ESF with automatic frame format unframed option Alarms and status conditions Out of Frame OOF Alarm Indication Signal AIS or Blue alarm Loss of...

Page 73: ...To DSU R Rcv Data a BB From DSU T Rcv Data b BB From DSU C RTS CA To DSU D CTS CB From DSU E DSR CC From DSU B Sig Gnd AB n a F DCD CF From DSU L LL To DSU U Ext Clk a DA To DSU W Ext Clk b DA To DSU...

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Page 75: ...rations Timing Option Descriptions In synchronous networks all device transmitters and receivers are usually referenced to a single master timing source This timing source or clock is frequently provi...

Page 76: ...network and channel transmit clock signals are derived from the clock recovered from the network receive data With Internal Timing the DSU provides the master clock but channel transmit clock signals...

Page 77: ...ng the clock frequency when passing it from one port to another Table C 1 Timing Option Reference Receive Timing With Receive Timing illustrated in Figure C 1 the network or a device at the remote end...

Page 78: ...as in a DACS Digital Access and Cross connect System network Figure C 1 Receive Timing Select the appropriate timing option for the customer equipment The DeskTop T1 DSU provides transmit timing on th...

Page 79: ...ive T1 clock from the network receive T1 data and uses it to clock T1 data into the receive buffer 5 The DeskTop T1 DSU also translates 6 the receive T1 clock to provide the channel transmit and recei...

Page 80: ...te DSU uses this as its timing reference 4 and loops it back to the DeskTop T1 DSU 5 The DeskTop T1 DSU recovers the receive T1 clock from the network receive T1 data and uses it to clock T1 data into...

Page 81: ...DSU in a private network with the customer equipment supplying the clock Figure C 3 DTE Timing Select the appropriate timing option for the customer equipment The DeskTop T1 DSU expects external timin...

Page 82: ...Top T1 DSU also translates 4 the receive T1 clock to provide the receive clock signal on the appropriate interface lead As in DTE Timing the customer equipment on the channel interface provides theoth...

Page 83: ...to Back Application In an in house data communications network two DeskTop T1 DSUs are connected back to back The only component connecting them is cable so there is no network to provide the timing...

Page 84: ...aster slave multiplexer application illustrated inFigure C 5 C the multiplexer at Site A is configured as the master i e the timing source and the multiplexer at Site B is configured as a slave With C...

Page 85: ...A AAAA AAAA AAAA AAAA AAA AAA A A A A A A A A A A A A A A A A A A AAAAAAAAAAAAAAAAAAA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA Host Computer Terminal Site A Site B Timing Option DTE Timin...

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Page 87: ...low Alarm Network LAD Network Low Average Density Config Error Configuration Error Network Alarms Network Out Of Frame A Network Out Of Frame NETWORK OOF alarm event occurs when the DSU misses twoout...

Page 88: ...t status of BPV error events Network Cyclic Redundancy Checksum A Network Cyclic Redundancy Checksum NETWORK CRCS error alarm event occurs when ESF framing is in use and the CRC 6 code calculated at t...

Page 89: ...has detected one of the following conditions The checksum computed bytheDSU for its configuration doesnot match the one it stored at the time the configuration was performed The settings of switchban...

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Page 91: ...2 13 DTE Interface 1 3 DTE Local Loopback 4 19 DTE Remote Digital Loopback with Self Test 4 23 DTE Remote Digital Loopback 4 21 DTE Self Test 4 17 Equipment List 1 4 Fault Isolation Procedure 4 3 Fea...

Page 92: ...ection 2 15 Starting DS0 Selections 2 12 Terminal Connection 2 15 Terminal Interface Configuration Screen 3 3 Diagnostics Screen 3 8 Monitor Screen 3 10 Test Procedure 4 4 What Are You Screen 3 12 Tim...

Page 93: ...hose products Inquiries concerning such trade marks should be made directly to those companies Copyright 1996 General DataComm Inc All rights reserved P O Box 1299 Middlebury Connecticut 06762 1299 U...

Page 94: ...General DataComm...

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