MT9075B Mitel Networks Corporation, MT9075B Datasheet - Page 33

• Manufacturer Part Number: MT9075B
• Description: E1 Single Chip Transceiver
• Manufacturer: Mitel Networks Corporation

Preliminary Information
Bit
7
6
5
4
3
2
1
0
Table 18 - Coding and Loopback Control Word
Name
MLBK
HDB3
MFRF
DLBK
RLBK
SLBK
PLBK
(0)
(0)
(0)
(0)
(0)
(0)
(0)
---
(Page 01H, Address 15H)
Unused.
Metallic Loopback. If one, then the
external RRTIP and RRING signals
are isolated from the receiver, and
TTIP and TRING are internally
connected to the receiver analog
input instead. If zero, metallic
loopback is disabled.
High Density Bipolar 3 Encoding.
If zero, HDB3 encoding is enabled
in the transmit direction. If one, AMI
signal without HDB3 encoding is
transmitted.
decoded in the receive direction.
Multiframe Reframe. If one, for at
least one frame, and then cleared
the MT9075B will initiate a search
for a new signalling multiframe
position.
activated
transition of the MFRF bit.
Digital Loopback. If one, then the
digital stream to the transmit LIU is
looped back in place of the digital
output of the receive LIU. Data
coming out of DSTo will be a
delayed version of DSTi. If zero, this
feature is disabled.
Remote Loopback. If one, then all
bipolar data received on RRTIP/
RRING are directly routed to TTIP/
TRING on the PCM 30 side of the
MT9075B. If zero, then this feature
is disabled.
ST-BUS Loopback. If one, then all
time slots of DSTi are connected to
DSTo on the ST-BUS side of the
MT9075B. If zero, then this feature
is disabled. See Loopbacks section.
Payload Loopback. If one, then all
time slots received on RTIP/RRING
are connected to TTIP/TRING on
the ST-BUS side of the MT9075B
(this excludes time slot zero). If
zero, then this feature is disabled.
Functional Description
Reframing
on
HDB3
the
function
is
one-to-zero
always
is
Bit
7
6
5
4
3
2
1
0
Table 19 - Transmit Alarm Control Word
DSToDE
CSToDE
64KSEL
REFRM
TAIS16
Name
TAIS0
TAIS
TE
(0)
(0)
(0)
(0)
(0)
(0)
(0)
(0)
(Page 01H, Address 16H)
Transmit Alarm Indication Signal.
If one, an all ones signal is
transmitted.
operation.
Transmit AIS Time Slot Zero. If
one,
transmitted in time slot zero. If zero,
time slot zero functions normally.
Transmit AIS Time Slot 16. If one,
an all ones signal is transmitted in
time slot 16. If zero, time slot
functions normally.
Transmit E bits. When CRC-4
synchronization is achieved, the E-
bits transmit the received CRC-4
comparison results to the distant
end of the link, as per G.704. That
is,
synchronization is lost, the transmit
E-bits will be zero. If one, and CRC-
4
transmit E-bits will be one.
Reframe. If one for at least one
frame, and then cleared, the device
will initiate a search for a new basic
frame position. Reframing function
is activated on the one-to-zero
transition of the REFRM bit.
64 KHz Select. If one, a 64 KHz
signal
extracted received 2048 kbit/sec.
clock is output on RxFP/Rx64KCK
(pin 47 in PLCC, 35 in MQFP). If
zero that pin outputs an 8 KHz
signal derived from the extracted
clock.
DSTo Data Enable. If zero, DSTo is
enabled. If one, DSTo will be
tristated if one of the following
conditions exists: LIU loss of signal,
loss
(SYNC=1), loss of CRC4 sync
(CRCSYN=1) or AIS.
CSTo Data Enable. If zero, CSTo is
enabled. If one, CSTo will be
tristated if one of the following
conditions exists: loss of multiframe
sync (MFSYNC=1), or AIS16 =1
synchronization
when
Functional Description
of
an
divided
terminal
all
TAIS=0 for
zero
ones
down
MT9075B
and
is
frame
signal
from
lost
normal
CRC-4
sync
the
the
is
33