MT9079 Mitel Semiconductor, MT9079 Datasheet - Page 25

• Manufacturer Part Number: MT9079
• Description: CMOS ST-BUS FAMILY Advanced Controller for E1
• Manufacturer: Mitel Semiconductor

Transmit National Bit Buffer (Page D)
Page 0DH, addresses 10000 to 10100 contain the
five bytes of the transmit national bit buffer (TNBB0 -
TNBB4 respectively). This feature is functional only
in processor and controller modes when control bit
NBTB=1.
The transmit national bit buffer is not cleared by the
RST function, but is cleared by the RESET function.
Receive National Bit Buffer (Page E)
Page 0EH, addresses 10000 to 10100 contain the
five bytes of the receive national bit buffer (RNBB0 -
RNBB4 respectively). This feature is functional only
in processor and controller modes.
Table 24 - Receive National Bit Buffer Bytes Zero to
Table 23 - Transmit National Bit Buffer Bytes Zero
7 - 0
7 - 0
Bit
Bit
TNBBn.F15
RNBBn.F15
RNBBn .F1
TNBBn .F1
Name
Name
-
-
to Four (Page D)
Four (Page E)
Transmit S
This
transmitted in bit position n+4 of
channel zero of frames 1, 3, 5, 7, 9,
11,
multiframe alignment is used, or of
consecutive
CRC-4 multiframe alignment is not
used. n = 0 to 4 inclusive and
corresponds to a byte of the receive
national bit buffer.
Receive S
This byte contains the bits received
in bit position n+4 of channel zero of
frames 1, 3, 5, 7, 9, 11, 13 and 15
when CRC-4 multiframe alignment
is used, or of consecutive odd
frames when CRC-4 multiframe
alignment is not used. n = 0 to 4
inclusive and corresponds to a byte
of the receive national bit buffer.
Functional Description
Functional Description
13
byte
and
an+4
an+4
odd
contains
Bits Frames 1 to 15.
Bits Frames 1 to 15.
15
frames
when
the
CRC-4
when
bits
Control Page 1
Tables 25 to 39 describe the bit functions of the page
1 control registers. ( ) in the “Name” column of these
tables indicates the state of the control bit after a
RESET or RST function.
4 - 0
Table 25 - Multiframe, National Bit Buffer and DL
Bit
7
6
5
Sa4 - Sa8
(00000)
MFSEL
Name
NBTB
ASEL
(0)
(0)
(0)
(Page 1, Address 10H)
Selection Word
AIS Select. This bit selects the crite-
ria 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 con-
secutive double-frame periods (512
bits per double-frame).
Multiframe Select. This bit deter-
mines which receive multiframe sig-
nal (CRC-4 or signalling) the RxMF
signal is aligned with. If zero, RxMF
is aligned with the receive signalling
multiframe. If one, the RxMF is
aligned with the receive CRC-4 multi-
frame.
National Bit Transmit Buffer. When
one, the transmit NFAS signal origi-
nates from the transmit national bit
buffer; when zero, the transmit NFAS
signal originates from the TNU4-8
bits of page 1, address 12H.
A one selects the bits of the
non-frame alignment signal for a 4
kbits/sec. data link channel. Data link
(DL) selection will function in termina-
tion mode only; in transparent mode
Sa4 is automatically selected - see
MODE control bit of page 1, address
11H. If zero, the corresponding bits of
transmit non-frame alignment signal
are programmed by the non-frame
alignment control word.
Functional Description
MT9079
4-261