ISO-CMOS MT8979
BIT
NAME
DESCRIPTION
7,
6,
5
A(N),
B(N),
C(N)
Transmit Signalling Bits for Channel N: These bits are transmitted on the CEPT 2048
kbit/s link in bit positions 1 to 4 of timeslot 16 in frame N, 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 CSTi1 channel from which the bits are sourced, the
telephone channel with which the bits are associated and the frame on the CEPT link on
which the bits are transmitted. For example, the bits input on the CSTi1 pin on channel 3
are associated with telephone channel 3, which is timeslot 3 of the CEPT link, and are
transmitted 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 be given the values ‘1, 0‘ and ‘1‘
respectively. The combination ‘0000‘ for ABCD bits should not be used for telephone
channels 1 to 15 as this would interfere with multiframe alignment.
& 4
& D(N)
3,
2,
1
A(N+15),
B(N+15),
C(N+15)
Transmit Signalling Bits for Channel N+15: These bits are transmitted on 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 range 1
& 0
& D(N+15) to 15 and refers to both the channel on the CSTi1 stream where the bits are supplied and
the frame on the CEPT link on which the bits are transmitted, and indirectly indicates the
telephone channel with which the bits are are associated. For example, the bits input on
the CSTi1 pin on channel 3 are associated with telephone channel 18, which is timeslot 19
of the CEPT link, and are transmitted in bits positions 5 to 8 of timeslot 16 in frame 3 of
each multiframe on the CEPT link .
Table 6. Channel Associated Signalling: Data Format for CSTi1 Channels 1 to 15
BIT
7
NAME
IU0
DESCRIPTION
International Use 0: When CRC is disabled, this bit is transmitted on the CEPT 2048
kbit/s link in bit position 1 of timeslot 0 of frame-alignment frames . It is reserved for
international use and should be kept at ‘1’ when not used. If CRC is enabled, this bit is not
used.
6-0
FAF2-8
Transmit Frame Alignment Frame Bits 2 to 8: These bits are transmitted on 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 be set to ‘0011011‘.
Table 7. Frame Alignment Signal: Data Format for CSTi1 Channel 16
4-173
MITEL [ MITEL NETWORKS CORPORATION ]
