- Silicon Laboratories, Inc. Modem User Manual

AN93
Rev. 1.3 147
6.2.2.4. Special Requirements for Serbia and Montenegro
The following are special network requirements for Serbia and Montenegro. These specifications are based on the
best information available and are believed to be correct.
 DC Feed: 48 or 60 V
 Feeding Bridge: 2 x 400  or 2 x 500 
 Network Impedance: 600 resistive
 On-Hook (Idle State) Noise: < –60 dBm
 On-Hook ac (Ringer) impedance: >2.5 k
 DTMF Transmit: –11 to –9 dBm and –8 to –6 dBm
 Data Transmit Level: 0 dBm to –15 dBm in 1 dB steps (average –13 dBmo)
 Out-of-band energy: not specified
 Pulse Dial: 1.6/1 ±15 % (pulse/pause)
Rep Rate: 10 pps
Interdial Pause: 250 ms <x> 800 ms, ±10 %
 Ring signal: 25 Hz 80–90 V
RMS

Dial Tone: 425 Hz ±15 %
Level: –8 dBm > x > –12 dBm
Cadence: 200 ms ±10% ON
300 ms ±10% OFF
700 ms ±10% ON
800 ms ±10% OFF
 Busy Tone: 425 Hz ±15 %
Level: –8 dBm > x > –12 dBm
Cadence: 500 ms ±10 % ON
500ms ±10% OFF
6.2.3. Blacklisting
Blacklisting prevents dialing the same phone number more than three times in three minutes. Any attempt to dial a
fourth time within three minutes results in a BLACKLISTED result code. If the blacklisting memory is full, any dial to
a new number results in a BLACKLIST FULL result code. The number of allowable calls may be adjusted in S43. If
S43 = 3, the third call in S44 seconds is blacklisted. The blacklisting time may be adjusted with register S44
(second units). A number is added to the blacklist only if the connection fails. The S42 register controls blacklisting.
Any number that is currently blacklisted is reported with the %B command.
S42 Blacklisting
0 (default) Disabled
1 Enabled
AT Command Function
%B Report blacklisted number (if
any) followed by OK
Example: AT%B\r
5121234567
OK