Paradise Datacom P300 Series Installation & Operating Handbook page 226

Rx Fault: CAS Multiframe sync lost
Rx Fault: Final data is all ones (AIS)
Rx Fault: X.50 de-stuff sync lost
Rx Fault: Final BER > 1E-3 [AIS Forced]
Rx Fault: <line> off, <DTE/DCE> not ready
Rx Fault: <line> off, DCE not accp't Rx data
P300H P300 Series Modem Installation and Operating Handbook
the standard IBS/SMS multiframe period can be long (1 sec at 32kbps) and it may be best to use
Custom IBS without a TS32 MF for rates of below 32kbps to improve the acquisition time if the
carrier is momentarily lost.
The modem cannot find the IBS CAS Multiframe sync on the receive data although it has found
Frame sync and TS32 Multiframe sync (otherwise the Frame/Multiframe sync messages above
would display). CAS Multiframe sync used to convey either
1) Channel Associated Signalling (CAS) in G.732 Drop/Insert modes using CAS,
2) To maintain the identity of a group of timeslots (for the `Odd values of N` such as N=7 etc).
3) To maintain Robbed Bit Signalling (RBS) in selected in T1-D4 or T1-ESC Drop/Insert modes.
Be aware that most competing modems do not support the use of a CAS Multiframe to provide any
of these three functions.
Check as follows for each use:
1) The Tx modem is set to operate in CAS mode if CAS signalling is to be conveyed within the
IBS/SMS overhead (one of the questions in the Change, Tx, Baseband, Drop menu dialogue)
2) If the Tx modem cannot use a CAS Multiframe to maintain the TS identity for the `Odd values of
N`, then to prevent this modem seeking a CAS multiframe for one of these `Odd value of N`, in the
Change, Rx, Baseband, Insert menu dialogue, when prompted TS identity over satellite: [?]
1=Maintain (normal) 2=Don't care, select Don t Care
3) If the Tx modem cannot use a CAS Multiframe to maintain RBS over satellite, in the Change, Rx,
Baseband, Insert menu dialogue, when prompted T1 RBS over satellite: [?] 1=Normal (or no RBS)
2=Maintain RBS, select Normal (or no RBS) .
The final customer data after demodulation, error correction, deframing and descrambling is all ones.
This is normally used to indicate an upstream equipment fault (such as a lack of input clock at the Tx
end), it is not a modem fault. See note 4.
In IBS modes at 48kbps or 56kbps the IBS specification (IESS 309) specifies that the 48/56kbps
data is `bit stuffed` up to 64kbps according to X.50 prior to IBS framing. The bit stuffing adds an 80
bit-repeating pattern which is detected at the Rx end then removed to return the data to 48/56kbps.
This message indicates the modem cannot find the 80-bit pattern in order to remove it. Check the
data is intended to be 48/56kbps X.50 stuffed to 64kbps, not raw 64kbps data. Refer also to the
Change, User, Operation, Terr/Sat, and X.50 AIS dialogue description for a discussion about AIS in
X.50 modes.
The User (final) Bit Error Rate is worse than 1x10
what action to take when the BER is bad is not set to Ignore (Change, User-Opt, Operation, Actions,
BER Action). The fault is always displayed, although the actions can be cancelled by selecting
Ignore. The source for the BER measurement is user defined (Change, User-Opt, Operation,
Satellite, BER est ). Normally this should be set to Auto , however it may be user set to other BER
sources if required. It is possible to manually set the source to the inner FEC (Turbo/Vit/Seq), even
when the outer FEC (RS) is active, thereby not including the effects of the RS error correction in the
displayed user BER. Check this remains set to Auto unless there is good reason.
<Line> depends on the interface in use (eg RS422 DCE= TR , V.35= DTR ). This is a DC control
line, which is used to indicate the terrestrial equipment is functioning properly. The <line> switching
off may be user set to cause this fault or be ignored (Change, Terr-Int, Control Lines). See note 5.
<Line> depends on the interface in use and is only available if the modem is fitted with a DTE
interface card (eg RS422 DTE= CS , V.35= CTS ). This is a handshake line, which is raised in
response to our RS/RTS line (if the modem interface is a DTE), which in turn indicates the output
data is valid (ie demod locked and FEC/deframing OK). Its status can be used to determine if the
terrestrial device is accepting the modems output data. The <line> switching off may be user set to
cause this fault or be ignored (Change, Terr-Int, Control Lines). See note 5
-3
. [AIS Forced] is only shown if the user option of
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