10 (34)
BRU3 MANUAL
BRU3 MANUAL, Doc.no: 155 16-ANNA 805 08 Uen, Rev H, 2003-02-07
4.1
Telephone Modem Boards
The telephone modem, which supports the CCITT V.32 and V.32bis standards,
consists of two separate boards, the FE Modem Board V.32 (FMB) and the FE
Adaptation Board (FAB). Depending on national requirements issued by the
telecommunications administration in your country, different versions of the
FAB may be used. Also, depending on the BRU3 variant, the telephone modem
may not be installed.
Two-wire leased, four-wire leased or switched lines are used for data
transmission. The maximum transmission rate is 14 400 bits/sec. The modem is
connected to the computer part via a synchronous serial circuit.
Asynchronously transferred AT/Hayes commands are used for modem
configuration and control.
The software used by the modem is installed from the main processor and stored
in a memory.
The FMB does not include a reset button. To reset the FMB and FAB, a power
off-operation is necessary.
4.1.1
V.11 and V.28 Serial Interfaces
The FE Connection board (FNB) includes conversion circuits for V.11 and V.28
standards for the serial interfaces. It also includes voltage protection and filters
for the modem, the V.11, the V.28 and the console ports.
