RFL IMUX 2000 - 5.7 SETTING E1 FRAME FORMAT AND LINE CODE (TSEL Group)

Because RFL™ and Hubbell® have a policy of continuous product improvement, we reserve the right to change designs and specifications without notice.
5.7 SETTING E1 FRAME FORMAT AND LINE CODE (TSEL Group)
The TSEL (E1 Select) Group is used to set E1 frame format and line code. The functions available in
the TSEL group are explained in Table 5-4.
Table 5-4. TSEL group
Function Description
CAS
CCS
Channel Ass
ociated Signaling. A method of utilizing tim
e sl
ot 16 to pass signaling information
between nodes. Turning off CAS selects CCS signaling.
Co
mmon Channel Signaling. This method is not supported by RFL channel modules. Time slot 16 is
available for data traffic. CCS is mutually exclusive with CAS.
AMI
HDB3
Alternate Mark In
version. A bipolar line code comp
os
ed of positive pulses, negative pulses, and zeroes.
In an AMI-encoded signal, every pulse ha
s the opposite polarity of the pulse that preceded it, regardless
of the number of zeroes between them. The major limitation of AMI is that it cannot support
64-Kbps clear-channel capability, due to the possibility of an excessive number of zeros.
Hig
h Density Bipolar of order 3. A modified bipolar line code in which strings of four consecutive
zeroes are replaced with special codes of four bits c
ontai
ning AM
I violations. This coding retains the
original coding bit rate while ensuring a minimum ones density in the transmitted data stream. This allows
unrestricted 64 Kbps clear-channel cap
ab
ility. The only limitation to HDB3 is that some older carrier
networks cannot support it.
The AMI and
HDB3 line codes are mutually exclusive
func
tions. HDB3 is the factory-default line
code.
RFL This function is not used in E1.
ANSI This function is not used in E1.
ATT This function is not used in E1.
CRC4 Cyclic Redundancy Check. This provides an integral error checking mechanism within the time slot
0 data package. Enabling CRC4 will set the syste
m into a 16
frame multi-frame mode. Disabling
CRC4 will place the system into a single frame (with the FAS in every other time slot 0).
IMUX
2000E1 RFL Electronics Inc.
January 1, 2008 5-16 (973) 334-3100