ISO-CMOS MT8979
BIT
7-4
NAME
MA1-4
DESCRIPTION
Receive Multiframe Alignment Bits 1 to 4: These are the bits which are received
from the CEPT 2048 kbit/s link in bit positions 1 to 4 of timeslot 16 of frame 0 of the
multiframe. They should all be ‘0‘.
3
2
X1
Y
This is the bit which is received on the CEPT 2048 kbit/s link in bit position 5 of
timeslot 16 of frame 0 of the multiframe. It is a spare bit which should be ‘1‘ if unused.
It is not debounced.
This is the bit which is received on the CEPT 2048 kbit/s link in bit position 6 of
timeslot 16 of frame 0 of the multiframe. It is used to indicate the loss of multiframe
alignment at the remote end of the link. A ‘1‘ on this bit is the signal that multiframe
alignment at the remote end of the link has been lost. A ‘0‘ indicates that multiframe
alignment is detected. It is not debounced.
1,0
X2,X3
These are the bits which are received on the CEPT 2048 kbit/s link in bit positions 7
and 8 respectively, of timeslot 16 of frame 0 of the multiframe. They are spare bits
which should be ‘1‘ if unused. They are not debounced.
Table 10. Received Multiframe Alignment Signal: Data Format for CSTo Channel 0
BIT
NAME
DESCRIPTION
7,
6,
5
A(N),
B(N),
C(N)
Receive Signalling Bits for Channel N: These are the bits which are received from the
CEPT 2048 kbit/s link in bit positions 1 to 4 of timeslot 16 in frame N (frame #), and are the
A, B, C and D signalling bits associated with telephone channel N. The value of N lies in
the range 1 to 15 and refers to the channel on the CSTo stream on which the bits are
output, the telephone channel with which the bits are associated and the frame on the
CEPT link on which the bits are received. For example, the bits output on the CSTo
stream on channel 3 are associated with telephone channel 3, which is timeslot 3 of the
CEPT link, and are received on bits positions 1 to 4 of timeslot 16 in frame 3 of each
multiframe on the CEPT link . If bits B, C or D are not used they should have the values ‘1,
0‘ and ‘1‘ respectively. The combination ‘0000‘ for ABCD bits should not be found for
telephone channels 1 to 15 as this implies interference with multiframe alignment.
& 4
& D(N)
3,
2,
1
A(N+15),
B(N+15),
C(N+15)
Receive Signalling Bits for Channel N+ 15: These are the bits which are received from
the CEPT 2048 kbit/s link in bit positions 5 to 8 of timeslot 16 in frame N, and are the A, B,
C and D signalling bits associated with telephone channel N+15. The value of N lies in the
& 0
& D(N+15) range 1 to 15 and refers to both the channel on the CSTo stream where the bits are output
and the frame on the CEPT link on which the bits are received, and indirectly indicates the
telephone channel with which the bits are are associated. The associated channel is
N+15.
For example, the bits output on the CSTo stream on channel 3 are associated with
telephone channel 18, which is timeslot 19 of the CEPT link, and are received on bits
positions 5 to 8 of timeslot 16 in frame 3 of each multiframe on the CEPT link .
Table 11. Received Channel Associated Signalling: Data Format for CSTo Channels 1 to 15
BIT
7
NAME
IU0
DESCRIPTION
International Use 0: This is the bit which is received from the CEPT 2048 kbit/s link in bit
position 1 of timeslot 0 of frame-alignment frames . It is reserved for the CRC remainder or
for international use.
6-0
FAF2-8
Frame Alignment Signal Bits 2 to 8: These are the bits which are received from the
CEPT 2048 kbit/s link in bit positions 2 to 8 of timeslot 0 of frame-alignment frames.
These bits form the frame alignment signal and should have the values of ‘0011011‘.
Table 12. Received Frame Alignment Signal: Data Format for CSTo Channel 16
4-175
MITEL [ MITEL NETWORKS CORPORATION ]
