KE LOGEM 928, Operation Manual

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Operation Manual V.34 - Modems, Version 07/97
S1 M2 D1 M5 D2 A/O Da/Te
LOGEM ®
928
Chapter 1
Modem Description
1.2 AT Commands
The AT command set is an international standard developed by the US
modem manufacturer Hayes. During command mode any modem
commands or modem reports are transfered asynchronously to the data
terminal equipment (DTE).
A command line has to start with an AT. The modems feature an integrated
automatical baud rate detection (up to 57600bit/s) that may be
deactivated.
1.3 Compatibility
The modems described here are functionally compatible to the duplex
operation modes of the models LGM 1200H1 and LGM 2400D2.
1.4 V.25bis Commands
The ITU-T recommendation is an international standard for automatic
dialing during synchronous or asynchronous operation modes.
1.5 Automatic Dialing
The modems come with an integrated automatical dialing feature for data
connections that may be controlled using either the V.25bis or the AT
command set. An integrated memory for calling numbers is included as
well. The dialing can be performed with pulse or tone (multi frequency)
dialing procedures.
Attention!
After data transmission the receiver must be onhook as the connection
remains operational at full charges otherwise.
1.6 Data Compression and Data Protection
To prevent from data transmission errors on low quality telephone lines
the modems can utilize the V.42 protocol or the Microcom Networking
Protocol MNP 4 during the operation modes acc. to V.32bis, V.32, V.22,
V.22bis and V.21. As an addition data compression is possible with MNP5
or V.42bis protocols.