Verilink 2048 (34-00179) Product Manual User Manual

Page 11

2-4

Installation

2048 PMU/NTU

Alive (KA) option. The PMU expects the framing format to
be the same on the equipment and network sides.

Network Line Code: Position S5-4 sets the network line
code for the E1 signal.

Down: HDB3 Up: AMI

CRC4: Position S5 -5 enables or disables the CRC4 fram-
ing mode. If enabled, the PMU will transmit the CEPT

CRC4 multiframe format and also expects to receive the

same format. The CRC4 checksum is the bases for obtaining
the performance monitoring data, so it important that this
position is enabled.

The PMU also expects to receive a CRC4 formatted input. If
the PMU is configured for CRC4 and a non-CRC4 format
signal is received, the PMU will indicate alarm conditions.
If the PMU is not configured for CRC4 and a CRC4 signal
is received, the PMU will ignore the CRC4 code. However,
the PMU will reframe the signal and the CRC4 code will not
be passed through the PMU.

The PMU always regenerates the CRC4 code, from the
equipment to the network. If both network and equipment
are configured the same, the PMU passes data from the net-
work to the equipment with regeneration only. In this mode,
the BPV, FBE, and CRC errors are passed through the PMU.

Insert CRC: Position S5-8 enables or disables the PMU to
insert CRC4 data on the network side of the PMU. If
enabled, the PMU will transmit and receive the CRC4 for-
mat on the network side only. Through the EM8000 network
manager, the PMU may be configured to enable/disable
CRC4 on either the network or equipment side.

AIS/ Keep Alive Selection: Positions S5-6 and S5-7 con-

figure the PMU for the following options:

2.5.7

Switch S6 (Bit Rate Selection)

DIP Switch S6 is used to select the bit rates for the USER,
PTT, and the Supervisory ports. The national bit ‘Pass’ or
‘Select’ option is also included on this switch.

Position S6 -7: National bit, Dn = Pass, Up = Select.

Position S6-8: Select ‘Dn’ (0) or ‘Up’ (1) for National Bit
data (only if position S6-7 is set for ‘Select’).

2.5.8

Switch S7 (Address)

DIP switch S7 is used to provide up to 250 unique unit
addresses. TxPORT’s EM8000 element manager recognizes
addresses from 1 to 250.

Switch S7 is an 8-position switch with positions labeled 1
through 8. The #1 position represents the least significant
bit (LSB) and the #8 position represents the most significant
bit (MSB) of the binary code. The eight switches are set to a
binary address code in the range of 1 to 250.

S5- 5

S5-8

CRC4 Configuration

NET

CRC

DTE

CRC

CRC ON, Insert CRC OFF

CRC ON, Insert CRC ON

CRC OFF, Insert CRC OFF

OFF

CRC OFF, Insert CRC ON

OFF

S5-6

S5-7

AIS / Keep Alive

AIS is unframed all ones

AIS is framed all ones
(only active toward network)

Line Loop Back (LLB)

N / A

Pos

1.2 kb/s

2.4 kb/s

9.6 kb/s

19.2 kb/s

SUPV

USER

NMS

PTT

NMS

Switch

Nat’

LSB

MSB

Binary values

Switch