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4.0 General Operation and Special Features
Changing the Operating Mode Fallback parameter to 1 has the following effects:
•The Modem is configured for V.22 bis 2400 bps/V.22 1200 and 600 bps/V.21 300 bps/V.23 1200/75 bps fallback operation. As a result, 600 and 1200/75 bps appear as additional selections on the SPEED LIMIT LCD screens.
•Fallback to V.22 bis Bell 212A and Bell 103 compatibility is disabled.
•An AT command is available (in Hayes mode only) that allows control over operating mode as follows:
The preferred mode is V.32 (9600 or 4800 bps, asynchronous/ synchronous, full duplex); however, if the other modem does not support the V.32 standard, the Modem falls back to one of the modes listed below. The fallback modes are listed in the order in which they are attempted by the Modem in normal operation.
Table 4-5. V.22 bis/BELL 212A/BELL 103 FALLBACK (DEFAULT).
MODE | DESCRIPTION | |
V.22 bis | 2400 bps asynchronous/synchronous | |
Bell | 212A | 1200 bps asynchronous/synchronous |
Bell | 103 | |
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All modes are full duplex.
If V.22 bis/V.22/V.21/V.23 fallback operation is enabled, the following fallback modes are available. As in the previous list, the modes are listed in the order in which they are attempted by the Modem.
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