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Semiconductor Group
301
09.98
PEB 22554
Operational Description T1 / J1
Framer Mode Register 4 (Read/Write)
Value after RESET: 00
H
AIS3…
Select AIS Condition
0…
AIS (blue alarm) is indicated (FRS0.AIS) when two or less
zeros in the received bit stream are detected in a time interval
of 12 frames (F4, F12, F72) or 24 frames (ESF).
1…
AIS (blue alarm) detection is only enabled when QuadFALC is
in asynchronous state. The alarm is indicated (FRS0.AIS) when
– three or less zeros within a time interval of 12 frames (F4,
F12, F72), or
– five or less zeros within a time interval of 24 frames (ESF)
are detected in the received bit stream.
TM…
Transparent Mode
Setting this bit enables the transparent mode:
In transmit direction bit 8 of every FS/DL time-slot from the system
internal highway (XDI) is inserted in the F-bit position of the outgoing
frame. Internal framing generation, insertion of CRC and DL data is
disabled.
XRA…
Transmit Remote Alarm (Yellow Alarm)
If high, remote alarm is sent via PCM route. Clearing the bit will
remove the remote alarm pattern. Remote alarm indication depends
on the multiframe structure as follows:
F4:
bit2 = 0 in every speech channel
F12:
– FMR0.SRAF = 0: bit2 = 0 in every speech channel
– FMR0.SRAF = 1: FS-bit of frame 12 is forced to ‘1’
ESF: –
FMR0.SRAF
=
0:
11111111000…’ in data link channel
– FMR0.SRAF = 1: bit2 = 0 in every speech channel
F72: bit2 = 0 in every speech channel
pattern
‘1111111100000000
SSC1/0…
Select Sync Conditions
Loss of Frame Alignment (FRS0.LFA or opt. FRS0.LMFA) is declared
if
00 = 2 out of 4 framing bits
7
0
FMR4
AIS3
TM
XRA
SSC1
SSC0
AUTO
FM1
FM0
(x20)