CTC Union TRM01 User manual

Table of Contents
i
Chapter 1. Introduction …………………………………………... 1
1.1 General …………………………………………………….. 1
1.2 Functional Description ……………………………………. 1
1.3 Technical Specifications …………………………………... 3
1.4 T1 Signal Structure ……………………………………….. 4
1.5 Applications / Capabilities …………………………………6
Chapter 2. Installation ……………………………………………. 9
2.1 General …………………………………………………….. 9
2.2 Site Preparation …………………………………………… 9
2.3 Mechanical Assembly ……………………………………... 9
2.4 Electrical Installation ………………………………………10
2.5 Power Supply Modules …………………………………… 12
Chapter 3. Data Modules ………………………………………… 13
3.1 Data Modules Overview …………………………………... 13
3.2 Data Module LED Indicators …………………………….. 16
3.3 V.35 Data Module …………………………………………. 17
3.4 RS-530 Data Module ……………………………………… 18
3.5 RS-449 Data Module ……………………………………… 19
3.6 X.21 Data Module …………………………………………. 20
3.7 ET10 Ethernet Module ……………………………………. 21

Table of Contents
ii
Chapter 4. Loop Back Testing …………………………………... 23
4.1 General ……………………………………………………...23
4.2 User Activate Loop Back …………………………………. 23
4.3 T1 Link local digital loop back ……..…………….………. 23
4.4 Data Port local analog loop back ……………….………… 24
4.5 T1 Link remote loop back ………………………………… 24
4.6 BERT local loop back ……………...……………………… 25
4.7 BERT remote loop back for system test .………………… 25
Chapter 5. Troubleshooting ……………………………………… 27
5.1 General …………………………………………………….. 27
5.2 Connections .……………………………………………….. 27
5.3 Configuration ..…………………………………………….. 28
5.4 FT1 Card testing .………………………………………….. 29
Appendix A. DIP Switch Setting Tables ………………………. 33
Notes: …………………………………………………………………. 39
Technical Inquiry Card

Chapter 1. Introduction
1 TRM-01 APR 2000
1.1 General
The TRM-01 is a 4U (7") high 19" Rack, containing multiple T1
CSU/DSUs for Fractional T1 network access. The TRM-01 provides an
economic solution in high density T1 installations such as central offices. There
are 13 slots available for installation of FT1 Cards (G.703 Fractional T1) into
the TRM-01 compact RACK. An optional SNMP Card may be installed into
the last slot, for local and remote management purposes, leaving 12 slots
available for FT1 Cards. Each FT1 Card may be linked to a remote TTU-01
or TTU-01A stand alone T1 CSU/DSU Access Unit to provide a variety of
LAN-to-LAN, Video Conference, Host to client, or Host to Host applications
over T1 Network Services.
1.2 Functional Description
The TRM-01 may optionally incorporate two separate Power Module
supplies, which, depending on the model, may derive power from either an AC
power source (95~250VAC) or DC (-54 to -42VDC) power source. The power
supply modules provide for power redundancy and are hot swappable even
during the FT1 Cards' transmissions. The TRM-01 provides all interface
connections on the rear panel. BNC and Terminal Blocks are used for T1 Line
interface connections, while optional cable adapters are used to convert the
HDB26 DCE ports to V.35, RS-530, RS-449 or X.21. When an FT1/ET10
Card (Ethernet bridge interface) is installed in the TRM-01, the card can
provide either Ethernet bridging or repeating (non-filter mode) over the T1 link.
When cards are inserted in slots, LEDs on the front panel will show both the T1
Line and Data port statuses, Power Status, and any Alarm indications.
The FT1 Card data channels support user-selectable transmission rates,
which are integer multiples of 56Kbps or 64Kbps (fractional T1), up to a
maximum 2048Kbps (unframed T1), for a line attenuation of up to 43 dB on
twisted pair or coax cables. This provides an approximate operating range of up
to 2Km (over 22AWG wire).
The FT1 Card packs its data channel into user selected T1 link time slots.
The unused time slots may have IDLE code of 0xff or 0x7e inserted (in frame
mode) or they may insert the receive side time slot's data (In cascade mode).
The TRM-01 has three major types of FT1 Card data port interface
modules, which provide the desired interface: V.35, RS-530, or ET10 Ethernet.
X.21 and RS-449 interfaces are fully supported using the RS-530 (public) card
and appropriate X.21 and RS-449 adapter cables.

Chapter 1. Introduction
2 TRM-01 APR 2000
The TRM-01 and FT1 Cards fully meet all T1 specifications including
ITU-T G.703, G.704, G.706, G.732, and G.823.
Each FT1 Card features V.54 diagnostic capabilities for performing local
loop back and remote loop back. The operator at either end of the T1 line may
test both the FT1 Card and the line in the digital loop back mode. The loop
back is controlled by either a manual push-button switch or by the DTE
interface for V.35 or RS-530.
When the local loop back switch is activated, an internal 511 bit pseudo
random test pattern is generated, according to ITU-T, for direct end-to-end
integrity testing. The Err indicator LED flashes for each bit error detected.
Multiple clock source selection provides maximum flexibility in
connecting both the T1 and user data interface. The T1 link may be clocked
from the recovered receive clock, from user data port, or from an on-card
oscillator.
When the TRM-01 is ordered with an optional SNMP Card, the card is
placed in slot number 13. Each FT1 Card will have DIP Sw7-6 turned ON to
enable remote setting. In this mode, the other DIP switch settings are ignored
while the SNMP Card controls all settings (with the exception of termination
impedance). Control is accomplished either via local control on the
asynchronous RS-232 port with an ASCII terminal or via Ethernet and any
standard SNMP network management software. If the SNMP Card option is
not installed, slot number 13 may hold an additional FT1 Card.
Figure 1-1 : TRM-01 Block Diagram

Chapter 1. Introduction
3 TRM-01 APR 2000
1.3 Technical Specifications
T1 Link User Data Channels
• Framing Unframed/Framed V.35
D4(SF) RS-530
ESF RS-449
X.21
• Bit Rate 1.544Mbps
• Interface Type
Ethernet 10Base-T
AMI • I/F Connectors HDB26 female
• Line Code
B8ZS
100 Ω
• Line Code NRZ (except
Ethernet)
• Line
Impedance Balanced
• Receive Level 0 to –36dB
Transmit Level
• Data Rate 1536Kbps(unframe)
nx56 or nx64Kbps
where N equal
1 ~24
Clock ModesPulse
amplitude
3.00V ±10% (100Ω)
Mode 0
(DCT1)
Rx and Tx clock
recovered from T1
Zero
amplitude ±0.1V
• Transmit Frequency Tracking
Mode 1
(DCE2)
Rx and Tx clock
internal oscillator
Internal
timing ±30ppm Mode 2 (DTT1)
Sync to Rx clock
(transparent)
Loopback
timing ±50ppm Mode 3
(DTE2)
Tx from ETC and
Rx from ERC
External
timing ±100ppm Mode 4 (DTE3)
Tx and Rx both
from ETC
• Jitter
performance
According to ITU-T
G.824
CTS constantly ON
• Complies with ITU-T G.703,G.704,
G.706,G.733,G824
and ANSI T1 403
DSR constantly ON
except during test
BNC for unbalanced
• I/F connectors
5 pin Molex ™ for
balanced
• Handshaking
control signals
DCD constantly ON
(except during
signal loss)
• Timeslot
Allocation
User Defined
Table 1-1 : TRM-01 Specifications

Chapter 1. Introduction
4 TRM-01 APR 2000
1.4 T1 Signal Structure
The T1 line operates at a nominal rate of 1.544Mbps. The data transferred
over the T1 line is organized into frames, with each T1 frame containing 256
bits. The 256 bits are a total of the 24 time slots, each containing eight bits, that
carry the data payload.
T1 transmission utilizes two main types of framing: Superframe Format
(SF) and Extended Superframe Format (ESF). A T1 framing format that uses
the framing bit to provide maintenance and diagnostic functions. D4-frame - A
T1 line uses the D4 format, also known as the superframe (SF) format, to frame
data at the physical layer. The D4 format consists of 12 consecutive frames,
each separated by framing bits. Framing is necessary in order for equipment
receiving the T1 signal to be able to identify and extract the individual channels.
Superframe Format (SF)
SF - Also known as D4, T1 lines use this format to frame data at the
physical layer. The SF format consists of 12 consecutive frames, each separated
by framing bits.
Extended Superframe Format (ESF)
ESF is a framing format that consists of 24 consecutive frames separated
by framing bits. The ISDN specification advises that you use ESF with ISDN
D-channel signaling.
T1 line signal
The basic T1 line signal is coded using either the Alternate Mark
Inversion (AMI) or B8SZ rule.

Chapter 1. Introduction
5 TRM-01 APR 2000
In the AMI format, “ones” are alternately transmitted as positive and
negative pulses, whereas “zeros” are transmitted as a zero voltage level. AMI is
not used in most 1.544Mbps transmissions because synchronization loss occurs
during long strings of data zeros.
B8ZS: Abbreviation for bipolar with eight-zero substitution . A T-carrier
line code in which bipolar violations are deliberately inserted if user data
contains a string of 8 or more consecutive zeros. Note 1: B8ZS is used to ensure
a sufficient number of transitions to maintain system synchronization when the
user data stream contains an insufficient number of "ones" to do so. Note 2:
B8ZS is used in the European hierarchy at the T1 rate.
T1 link line coding
The TRM-01 supports two T1 line codes:
AMI coding.
B8ZS coding.
T1 framing formats
The TRM-01 supports three frame formats:
Unframed format.
SF Superframe Format.
ESF Extended Superframe Format.

Chapter 1. Introduction
6 TRM-01 APR 2000
1.5 Applications / Capabilities
In the following example, the TRM-01 is installed at an ISP's central
office and provides "last mile" access to corporate customers over dedicated T1
transmission lines. The customer site utilizes a single data port CSU/DSU,
which could be one of our pack series or standalone units. While utilizing
fraction T1 connections, the ISP can provide a variety of bandwidth options to
its customers. By varying timeslot assignments, data rates from 64Kbps up to
1536Kbps may be utilized in frame mode.
The FT1 Cards in the TRM-01 could all be set to internal oscillator
timing or they could receive timing from the DTE on the data port. The remote
units would all be set to recovery.
Figure 1-2 : T1 nest for ISP
In the next application example, the TRM-01 is used in a point-to-point
T1 line environment. Each FT1 Card acts as a stand alone Digital Access Unit,
connecting individual T1 lines to data port interfaces or bridging Ethernet LANs.
For any T1 link, one CSU/DSU should provide internal timing while the linked
unit should be set to recovery.
Figure 1-3 : Point-to-point Application of TRM-01