Cabletron Systems CSMIM-T1 Installation Manual page 147

When both the originate and answer modems are V.8 modems,
NOTE
setting 300 bps will make a V.21 connection.
Table 7-4 Modem Connections When %L1 or %L3 is Set
Mode Setting on
Originating Modem
V.34 (2400-28,800)
V.FC (14,400-28,800)
V.32bis (4800-14,400)
V.32 (4800-9600)
V.22bis (2400)
V.22[a] (1200)
V.22[b] (600)
Bell212A (1200)
Bell103 (300)
The following chart indicates the connections that the modem can
establish when %L4 is set. Both modems must support the V.8 protocol
when using %L4 or a connection will not be made.
CSMIM-T1 Hardware Installation Guide
Mode Setting on Answer Modem
Bell212A
V.22[a]
V.22
V.22[a]
V.22[a]
V.22[a]
V.22[a]
—
Bell212A
Bell103
Commands
Bell103
—
—
—
—
—
—
—
Bell212A
Bell103
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