MT9075A Mitel Networks Corporation, MT9075A Datasheet - Page 30

• Manufacturer Part Number: MT9075A
• Description: E1 Single Chip Transceiver
• Manufacturer: Mitel Networks Corporation

MT9075A
4-158
Table 13 - Multiframe National Bit Buffer and DL
4 - 0 S
Bit
7
6
5
Selection Word (Page 01H, Address 10H)
MFSEL
Name
NBTB
a4
ASEL
- S
a8
AIS Select. This bit selects the
criteria on which the detection of a
valid Alarm Indication Signal (AIS)
is based. If zero, the criteria is less
than three zeros in a two frame
period (512 bits). If one, the criteria
is less than three zeros in each of
two
periods (512 bits per double-frame).
Multiframe
determines
multiframe
signalling) the RxMF (pin 42 in
PLCC, 23 in MQFP) signal is
aligned with. If zero, RxMF is
aligned with the receive signalling
multiframe. If one, RxMF is aligned
with the receive CRC-4 multiframe.
National Bit Transmit Buffer. If
one, the transmit NFAS signal
originates from the transmit national
bit buffer; if zero, the transmit NFAS
signal originates from the TNU4-8
bits of page 01H, address 12H.
A one selects the corresponding S
bits of the NFA signal for 4, 8, 12,
16 or 20 kbits/sec. data link
channel. Data link (DL) selection will
function in termination mode only; in
transmit transparent mode S
automatically
TxTRSP control bit of page 01H,
address
corresponding bits of transmit non-
frame
programmed by the Non-Frame
Alignment
01H, address 12H).
Functional Description
consecutive
alignment
11H.
Control
signal
Select.
selected
which
If
Word
double-frame
(CRC-4
signal
zero,
This
-
receive
(page
a4
see
are
the
bit
or
is
a
Bit
7
6
5
4
3
2
Table 14 - Mode Selection Control Word
TxTRSP Transmit Transparent Mode. If
CRCM
Name
AUTY
TIU0
RST
---
(Page 01H, Address 11H)
Transmit International Use Zero.
When CRC-4 operation is disabled
(CSYN=1), this bit is transmit on
the PCM 30 2048 kbit/sec. link in
bit position one of time-slot zero of
frame-alignment
reserved for international use and
should normally be kept at one. If
CRC processing is used, i.e.,
CSYN =0, this bit is ignored.
CRC-4
activates the CRC-4 remainder
modification function when the
device is in transparent mode. The
received
modified to reflect only the changes
in the transmit DL. If zero, time slot
zero data from DSTi will not be
modified in transparent mode.
Reset. When this bit is changed
from zero to one the device will
reset to its default mode. See the
Reset Operation section for the
default settings.
Unused. Set high for normal
operation.
Automatic Y-Bit Operation. If
zero, the Y-bit of the transmit
multiframe alignment signal will
report the multiframe alignment
status to the far end i.e., zero -
multiframe alignment acquired, one
- lost. If one, the Y-bit is under the
manual control of the Transmit
Multiframe
Word.
one, the MT9075A is in transmit
transparent mode. No framing or
signaling is imposed on the data
transmit from DSTi onto the line. If
zero, it is in termination mode.
Preliminary Information
Functional Description
Modification.
CRC-4
Alignment
frames.
remainder
If
Control
It
one,
is
is