KE LOGEM 928, Operation Manual

Page: 16 / 200

16 Operation Manual V.34 - Modems, Version 07/97
Chapter 1
S1 M2 D1 M5 D2 A/O Da/Te
LOGEM ®
928
product line even allow for reconfiguration during an existing connection.
Three operation modes are available for different modem applications.
During software mode all modem configurations are performed using AT
or V.25bis commands. AT commands should be prefered generally as
V.25bis commands do not allow to set any registers. The command phase
is always asynchronous during utilization of AT commands. After dial up
data transmission is performed according to the selected synchronous
or asynchronous modulation procedure.
Compatible mode is employed to emulate duplex operation mode for
existing recent modems. Here the necessary modem is selected using
the DIP switches. The first 14 switches of the modem correspond to the
switches of the modem to be replaced. For this reason a terminal is not
necessary for modem configuration.
During mixed mode the modem operates with the AT mode but some
registers have to be selected with DIP switches as they are blocked for
software access.
1.1 Transmission Procedures
The modems operate with the ITU-T recommendations listed below:
• V.34 (2400 bit/s, 4800 bit/s, 7200 bit/s, 9600 bit/s,
12000 bit/s, 14400 bit/s, 16800 bit/s, 19200 bit/s,
21600 bit/s, 24000 bit/s, 26800 bit/s, 28800 bit/s,
duplex) synchronous and asynchronous
• V.32bis (14400 bit/s and 12000 bit/s, duplex)
asynchronous and synchronous
• V.32 (4800 bit/s, 7200 bit/s und 9600 bit/s, duplex)
asynchronous and synchronous
• V.22bis (2400 bit/s, duplex) synchronous and asynchronous
• V.22 (1200 bit/s, duplex) synchronous and asynchronous
• V.23 (75/1200 bit/s, 1200/75 bit/s, asymmetrical duplex) asynchronous
• V.21 (300 bit/s, duplex) asynchronous
• V.17, V.29, V.27ter (14400 bit/s, 12000 bit/s,
9600 bit/s, 4800 bit/s, 2400 bit/s, halfduplex)
send and receive fax
Modem Description