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Operation

3-5

1558A APS 

3.3.1

Supervisor Port

The front panel SUPV port allows the user to connect to the
1558A via a PC running the supplied APS LAPS (Local
Access protection software) application. This user interface
software allows the user to gain access to the unit configura-
tion data, unit status, unit performance, and perform local
and remote loopback testing.

Electrically, the SUPV port is RS232 and the data format is
19.2 Kb, asynchronous. The cable used to connect the PC to
the SUPV port is a DB9 (female) to 6-pin modular cable.
This cable is provided with the 1558A unit. The pin func-
tions for the SUPV port are shown in the following table. 

3.3.2

Power Indicators 

The 1558A has two green power LED indicators (Power A
and Power B). One or both of the indicators will be ON
when a nominal power source of -20 to -56 VDC is present
on the rear panel PWR A and PWR B screw terminals,
respectively. The indicator(s) will be OFF if the power is not
present at the respective power screw terminals. Only one
power input is required to operate the unit. If power redun-
dancy is crucial, both the Power A and Power B inputs
should be wired to an external -20 to -56 VDC source. The
1558A unit is shipped with a single 110 VAC to -48 VDC
wall power unit.

3.3.3

Bypass Indicator

The red BYPASS LED indicates whether or not the 1558A
is presently in a BYPASS mode of operation. The LED will
be ON if the unit has detected a CPU watchdog operational
fault. The LED will be OFF under normal operation. 

When active, the BYPASS mode connects the NET A T1
facility directly to the DTE port. In this mode, all of the
active electronics are bypassed. That is, the only elements in
the path are passive line protection circuitry components for
the NET A port and the DTE port. During BYPASS opera-
tion, the 1558A acts only as a passive device and does not
perform any signal regeneration functions. 

Activation of the BYPASS mode occurs when either the
CPU watchdog timer circuitry is defective (indicates a CPU
or software problem) or when power is removed from the
unit. The BYPASS mode is terminated when either the CPU
watchdog circuitry is determined to be normal or when
power is restored to the unit. 

3.3.4

Locked Indicator

The user can manually force and lock either the A or B T1
path as the active path by moving the PATH SELECT switch
from the AUTO position to either the A or B Path Select
positions. This action will force the 1558A to use the
selected path. Also, the 1558A is now manually locked to
this path and will not switch from it, even if the selected
path is in a failed state or subsequently fails. When the
1558A has been manually forced to either the A or B PATH,
the amber LOCKED LED indicator will be on. Moving the
PATH SELECT switch back to the AUTO position will turn
off the LOCKED LED and restore normal APS operation. 

Caution: Placing the 1558A in a manually locked
mode prevents the unit from performing automatic pro-
tection switching.

Pin 

SUPV Port Wiring

1

Not Used

2

Ground

3

Data, Out

4

Data, In

5

Ground

6

Not Used

Figure 3-2

1558A Front View 

A

SUPV

PWR

B

STATUS

A

BYPASS

LOCKED

B

A

B

ALM

LOS

LP

A

SELECT

AUTO

PATH

B

STATUS

PATH

RX BRDG

TX BRDG

N
E
T

A

RX BRDG

TX BRDG

N
E
T

B

DTE

LOS

RX BRDG

TX BRDG

D
T
E

TxPORT

LP

1558A

Summary of Contents for 1558A

Page 1: ...T R A N S P O R T Introduction Reference Manual 34 00228 2nd Edition 1558A APS ...

Page 2: ... 3 4 Status and Performance Information 3 4 Configuration Modes 3 4 Front Panel Controls and Indicators 3 4 Supervisory Port 3 4 Power Indicators 3 5 Bypass Indicator 3 5 Locked Indicator 3 5 Status Indicators 3 5 Manual Path Selector Switch 3 6 Path Status Alarm Indicators 3 6 Path Status LOS Indicators 3 6 Path Status Loop Indicators 3 6 Bantam Test Access Jacks 3 6 DTE Loop Indicator 3 6 DTE Lo...

Page 3: ...f California All rights reserved Redistributions in binary form must reproduce the above copyright notice this list of conditions and the following disclaimer in the documentation and or other materials provided with the distribution All advertising materials mentioning features or use of this software must display the following acknowledgment This product includes software developed by the Univer...

Page 4: ... or B8ZS Line Coding Integral ESF CSUs TR 54016 compliant 24 Hour Performance History Revertive and Non revertive Operation User Definable Alarm Switching Thresholds Proactive Call on Alarm Reporting requires manager Desk Top or Rack Mount Redundant Power Configurations AC or DC Bantam Test Access Jacks Complies with AT T 54017 Automatic Protection Switching 1991 FCC DOC UL and CSA Compliant 1 2 S...

Page 5: ... for a Class A digital device pursuant to Part 15 of FCC Rules These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause harmful interference to radio communi c...

Page 6: ...numeriques de la class A prescrites dans le Reglement sur le brouillage radioelectrique edicte par le ministere des Communications du Canada Port ID REN SOC FIC USOC P N 12 00635 6 0 N 04DU9 BN 04DU9 DN 04DU9 IKN 04DU9 ISN RJ48C 1 5 Warranty TxPORT warrants each unit against defects in material and workmanship for a period of five years from the date the unit was shipped to the customer If the uni...

Page 7: ... perform local loop testing 9 1001 029 2 PC to 1558A data cable 10 DB9 to 6 pin modular Standard with 1558A unit 30 00087 110 VAC to 48 VDC 200 mA max wall transformer unit 10 power cable Standard with 1558A unit 9 1001 004 010 RJ48 8 pin modular 10 cable Three cables come standard with the 1558A unit Contact the factory for additional cable lengths and types F 1559 000 XXXX 1559 APSM Manager Used...

Page 8: ...using ABAM cable 26 gauge shielded wiring E Verify that the T1 line is operating properly before you attempt to install the 1558A unit Both of the T1 lines should be checked for error free operation for at least 1 hour to insure that they are performing error free F If the unit is going to installed in a 19 equipment be rack verify that there is enough rack space available in the rack requires 1 7...

Page 9: ...power source 20 to 56 VDC to the rear panel screw terminal labeled PWR B DC and RTN If using the provided AC to DC wall power transformer connect the RED wire to the RTN ter minal the BLACK wire to the DC terminal and the GREEN wire to the GND terminal 2 4 3 Alarm Connections The 1558A has alarm contacts provided at the rear panel screw terminals labeled COMMON NC and NO The alarm relay is operate...

Page 10: ...ked and inspected and mounted the next step is to configure the unit All unit options are set by the switch positions on four 8 position DIP switches S1 S2 S3 and S4 on the rear of the 1558A unit The 1558A is shipped from the factory with all option switches in the OFF factory default position The follow ing paragraphs briefly describe the 1558A option switches NOTE After all of the option switche...

Page 11: ...ositions 5 7 are used to set the DSX signal level in feet for the DTE port The factory default is 0 to 133 feet for the DTE DSX setting 2 5 2 ROM Configuration The 1558A may be configured to boot operational parame ters from the internal ROM read only memory To config ure the 1558A to boot from ROM set S1 7 and S1 8 to the ON position and S1 6 to the OFF position With these set tings the 1558A wil...

Page 12: ...nd Path B local Path Integrity for Path A and Path B end to end The following T1 test equipment and miscellaneous cables will be required to perform the preservice tests Two T1 test sets one required at each APS location Two cables to go from the T1 test sets to the unit RJ48 DTE connectors at both ends Before proceeding the user should read and understand the background information presented in t...

Page 13: ...set should be running in sync and error free If not verify that the T1 test set framing and line coding set ting match the settings configured in the 1558A The 1558A unit is now looped back to the DTE port and the T1 test set should be indicating that it is detecting pattern sync and running error free If yes proceed to Path B Preservice Testing If no verify that Steps 1 4 have been completed prop...

Page 14: ...the T1 test set is configured to supply clock internal 2 6 3 Results The stand alone preservice testing verifies the operational integrity of the 1558A If either Path A or Path B failed but not both and the options have been verified the user should contact the factory for additional assistance refer to the General chapter 2 6 4 End to End Pre Service Testing The following paragraphs describe pres...

Page 15: ... BYPASS mode is active are line protection com ponents and test access jacks The BYPASS mode of opera tion is automatically implemented when either of the following occurs Power is removed from the unit external power failure CPU detects an internal operational fault If this occurs the front panel BYPASS LED red will be on to indicate that the 1558A has detected a unit fault and that it is now ope...

Page 16: ...th active and standby access paths exceed their specified thresholds service will be maintained on the currently active access path The switch from the active to the standby path is completely independent of any external equipment Switching from an active path to a standby path only involves the receive paths Path A and Path B not the transmit paths 3 2 1 Revertive and Non Revertive Switching The ...

Page 17: ... activated on the active path If the CSU Line Loop or Payload Loop activate signal is received by both paths simultaneously no change of LB state shall occur regardless of their current states The one way protection characteristic of the APS can result in split service operation That is service from the 1558A near APS to the 1558A far APS via one access path while the 1558A far APS to the 1558A ne...

Page 18: ...hat can configured by the user are Errored Seconds Consecutively Severely Seconds Loss of Signal and Loss of Framing These alarm parameters and their definition are described below Errored Seconds ES The user can define that the 1558A switches from the active line to the standby line when a cer tain number of errored seconds have been detected during the current 15 minute performance interval 900 ...

Page 19: ...urrently carrying the service This path is currently in a failed state This path is currently in an inhibit state The LB of this path is currently activated The other path is currently in a failed state The other path is currently in an inhibit state The LB of the other path is activated The manual locked control state Current status Current interval Occurrences Current interval Duration Current I...

Page 20: ... connects the NET A T1 facility directly to the DTE port In this mode all of the active electronics are bypassed That is the only elements in the path are passive line protection circuitry components for the NET A port and the DTE port During BYPASS opera tion the 1558A acts only as a passive device and does not perform any signal regeneration functions Activation of the BYPASS mode occurs when ei...

Page 21: ...jacks is described in the following table 3 3 11 DTE Loop Indicator The 1558A DTE port can be looped either locally or remotely by receipt of soft commands generated either from the LAPS software interface or from a far end unit When a loop has been activated the front panel DTE LP indicator amber will be ON If no loop is active the DTE LP indica tor will be OFF Note that a DTE loop interrupts ser...

Page 22: ...e eight pins found in the connector are described in the table below The 1558A unit comes with three ten foot RJ48 cables NET A NET B and DTE 3 4 3 DTE T1 Connection The DTE T1 modular jack is used to connect the 1558A to the customer premise equipment using a RJ48 modular cable Physically the DTE connector is RJ48 8 pin modu lar connector The DTE T1 port is not designed connect directly to a TELC...

Page 23: ...om the unit s RAM The ROM defaults are ES 20 CSES 2 LOS Yes LOF Yes and Line Availability Timer 60 Boot Modes The 1558A unit configuration can be set at power up by the parameters stored in the ROM RAM option switches or from the optional 1559 site manager Switch S2 Framing Errors The 1558A can be optioned to alarm based upon receipt of 32 or more consecutive framing errors This parameter can also...

Page 24: ...opied remove and store the original disk in a safe place 5 After removing the disk in drive A enter the following C LAPS laps 1 or laps 2 Entering LAPS 1 or LAPS 2 directs the program to use either COM 1 or COM 2 The computer responds by launch ing the LAPS application Once the application is running the user log on screen will be displayed and the user is prompted to Press the Enter key to begin ...

Page 25: ...ted cursor to make selections from menus and to select fields within screens that are to be operated upon The cursor can be moved using the standard terminal cursor control keys which are back space up arrow down arrow left arrow right arrow page up page down and delete For PC computers which do not have these particular keys or have only some of them a set of cursor control com mands are supporte...

Page 26: ...d and manipulated in the same manner Each circuit s identifica tion and status is displayed using the following fields NOTE Pressing the esc key will take the user back to the previous circuit list screen Pos This field specifies the circuit s unit address Stand alone 1558A units are assigned address starting with shelf 1 position 1 2 3 etc The factory default address setting of a 1558A is shelf 1...

Page 27: ...uits at one time The next six circuits if any can be viewed by pressing page down To show the six preceding circuits press page up An individual circuit can be specified at any time by enter ing the position designator at the message line prompt Shelf Pos and pressing return This designator must be typed as it is displayed For example the APS device in position 3 of shelf 1 would be specified as 1...

Page 28: ...ow SWO History This command field is used to access the 30 day Switch Occurrence History screen To access this infor mation move the cursor highlight to the SWO History field and press return The system responds by displaying the Occurrence History display see Screen 4 5 This display lists the last thirty day completed periods 24 hours and the number of switch occurrences for each of those days Th...

Page 29: ...field may be selected with the terminal arrow keys or cursor con trol commands A new selection is activated when return is pressed with the cursor still positioned on that field The actions initiated by each field are detailed below Clear Tests Resets any active loopbacks and turns off any applied patterns Clear Alarms Resets alarms at the specified end of the circuit Near Far Activating this fiel...

Page 30: ...s running Near CRC Errors A display only field for viewing the number of CRC errors which are received at the Near Target receive path Far CRC Errors A display only field for viewing the number of CRC errors which are received at the Far Target receive Far CRC Errors are only reported if the 1558A is configured as a Master Slave 1558A units do not report Far CRC Errors Reset Errors Pressing return...

Page 31: ...ected to the APS Errored Seconds This field is used to define the Errored Seconds threshold for an APS service as specified in AT T TR54017 The value may be set from 0 to 900 Consecutive SES This field is used to define the Consecu tive Severely Errored Seconds threshold for an APS service as specified in AT T TR54017 The value may be set from to 0 to 900 Line Avail Timer This field sets the time ...

Page 32: ...LBO Level B Displays the setting of the LBO level select switch for network Line B This field is a read only field and may only be manually changed by the user see Installation section DSX Level Eq Displays the setting of the DSX level select switch for the equipment side of the APS This field is a read only field and may only be manually changed by the user see Installation section Boot from Disp...

Page 33: ...p The following sections describe in detail how to perform loops and unloops of the 1558A equipment Note that all loops and unloops are performed at the Maintenance screen The location of the various loops is depicted in the 1558A Block Diagram shown in Figure 4 2 on page 4 11 The remainder of this chapter discusses these loops Reference to this block diagram may provide clarification 4 8 1 Near C...

Page 34: ... the cur sor highlight to the Loop field and toggle the field using the space bar until the field displays CO Facility Then momen tarily depress the return enter key The LAPS will initiate a CO Facility loop of the selected target After a few moments notice that the NEAR status field has changed from Soft Inhibit or Standby to Fac LP Also note that the 1558A front panel Loop LED indicator is on B ...

Page 35: ... loops the incoming T1 signal RX coming from the network NET A or NET B port back to the net work TX NET A or NET B Both the signal and CRC are regenerated In addition to looping the signal back to the network the signal is also transmitted to the DTE port To initiate a CPE Payload loop first target the path A or B that you want to test by moving the cursor highlight to the Target field and then u...

Page 36: ... The most common network interface loop up 5 bit pattern is 11000 The most common unloop 5 bit pattern for network interface devices is 11100 After selecting the 5 bit pat tern move the cursor back to the Loop field and press the return key The LAPS responds by sending the selected NET 5 bit code to the far end equipment for 5 seconds or more To unloop the network interface device simply move the ...

Page 37: ... if Master 1558A It is important to understand that the 1558A does not allow testing loop or BERT on the active path To perform test ing on a given path the user must first configure the path to the Standby mode Soft Inhibit mode or Manual Inhibit mode Once the path to be tested is in one of these modes the LAPS will allow the user to perform testing BERT testing can be performed either to loopbac...

Page 38: ... IN and OUT 3 7 T1 2 2 D Data Link Loop Backs 3 2 F FCC Requirements 1 2 Front Panel Indicators 3 4 L Location Header 4 2 Loss of Frame 3 1 Loss of Signal 3 1 M Main Menu 4 2 Maintenance Screen 4 6 Clear Alarms 4 6 CRC Errors Far 4 7 4 14 CRC Errors Near 4 7 4 14 Force 4 6 Lock 4 6 Loop 4 6 Pattern 4 7 Reset Errors 4 7 4 14 Runtime 4 7 4 14 Target 4 6 Test Time 4 7 4 14 Unlock 4 6 Unloop 4 7 Mount...

Page 39: ...S Service Select control 3 2 Site Preparations 2 1 Specifications 1 1 Switching Time 3 3 T Terminal Strip 3 7 TxPORT Customer Service 1 4 U User Log On 4 2 W Warranty 1 3 ...

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