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You have accessed an older version of a Paradyne product document. Paradyne is no longer a subsidiary of AT&T. Any reference to AT&T Paradyne is amended to read Paradyne Corporation.
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Purpose This special firmware release adds the ability of ARDIS cell sites to backup at 28.8 kbps using external AT&T Paradyne 3800Plus and 3900 Series (V.34bis) modems until the 3600 Series 28.8 kbps dial backup module (DBM) is available. Full backup capability is provided. Backup can be initiated automatically from the diagnostic control panel (DCP), or manually initiated from the DCP or a 6800 Series network management system (NMS).
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Figure 1. Point-to-Point Configurations with External V.34 Backup Configuring the DSU for External Backup This firmware release supports two modes of external backup so that the modem can: Originate a call. Answer a call. To support external backup, changes have been made to the configuration options in the Options (Opts) branch. To use the external backup feature, use the DSU Configuration option sets: DBM, Diagnostic (Diag) DBM, and Backup (Bkup).
Changes to Manual – Configuration Options Configuration Option AggrSwitch Removed AgSw Timing Removed ExtBU Enab, Disab AnswExtBU Enab, Disab Rate(Kbps) 28.8, 24.0, 19.2 TxClkSource DSU only: DSU-TDM: AnswExtBU Moved to DBM option set Does not appear if ExtBU is disabled. Does not appear if a 2-Port TDM/Flex is installed.
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Answering a Call When configured to answer a call, AnswExtBU (in the DBM option set) is enabled. The DSU raises DSR and monitors its DTR lead. When the modem raises DSR, raising DTR and indicating that a call is being established, the DSU switches data to the backup line –...