User`s guide

AT Commands
5-30 Modem 3600
Auto Retrain %E
This option allows the modem to automatically retrain in response to
poor received signal quality without reconnecting. The modem always
responds to a retrain request from the remote modem.
Automatic Rate Adaption %R
Automatic rate adaption (ARA) allows the modem to automatically
decrease the DCE rate when the allowable bit error rate is exceeded. If
the line condition improves the modem automatically increases the rate.
Select this feature by front panel operation or AT command. Options
include: disabled (factory default), low (BER= 1 in 10
5
), medium
(BER= 1 in 10
4
), high (BER= 1 in 10
3
).
The following guidelines apply to automatic rate adaption:
• Automatic rate adaption is disabled during direct mode.
• Manual rate adaption is disabled from the front panel when
automatic rate adaption is enabled.
• Only one increment or decrement in the DTE rate is allowed at a
time during rate adaption from the initiating modem.
• When online, initiator rate adaption occurs a maximum of every
12 to 14 seconds from the last occurrence of a rate adaption.
• After the modem drops data rate because of poor signal quality,
the line must improve by approximately 2.5 dB before an increase
in rate can occur.
Command Operation
%E Disable auto retrain
%E1 Enable auto retrain