Command Reference Manual
100722A
Conexant
3-39
+MCR: Report Syntax
Response: +MCR: <carrier>
<carrier> Alphanumeric code corresponding to the reported carrier. Defined values are:
B103 For Bell 103
B212 For Bell 212
V21 For V.21
V22 For V.22
V22B For V.22bis
V23C For V.23
V32 For V.32
V32B For V.32bis
V34 For V.34
V90 For V.90
K56 For K56flex
+MRR: Report Syntax
Response: +MRR: <tx_rate>,<rx_rate>
<tx_rate> Decimal transmit rate in bits/s.
<rx_rate> Decimal receive rate in bits/s.
Example: +MRR: 28800, 48000
3.2.4.3 %E - Enable/Disable Line Quality Monitor and Auto-Retrain or Fallback/Fall Forward
Controls whether or not the modem will automatically monitor the line quality and request a retrain (%E1) or fall back when
line quality is insufficient or fall forward when line quality is sufficient (%E2). The parameter value, if valid, is written to S41
bits 2 and 6.
If enabled, the modem attempts to retrain for a maximum of 30 seconds.
Syntax
%E<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0 Disable line quality monitor and auto-retrain.
1 Enable line quality monitor and auto-retrain.
2 Enable line quality monitor and fallback/fall forward. (Default.)
Result Codes
OK <value> = 0, 1, or 2.
ERROR Otherwise.
Fallback/Fall Forward.
When %E2 is active, the modem monitors the line quality (EQM). When line quality is insufficient, the
modem will initiate a rate renegotiation to a lower speed within the V.34/V.32 bis/V.32 (RC336) modulation speeds. The
modem will keep falling back within the current modulation if necessary until the speed reaches 2400 bps (V.34) or 4800 bps
(V.32). Below this rate, the modem will only do retrains if EQM thresholds are exceeded. If the EQM is sufficient for at least
one minute, the modem will initiate a rate renegotiation to a higher speed within the current modulation speeds. The rate
renegotiations will be done without a retrain if a V.32 bis connection is established.
Speeds attempted during fallback/fall forward are those shown to be available in the rate sequences exchanged during the
initial connection. Fallback/fall forward is available in error correction and normal modes, but not in direct mode or
synchronous mode with external clocks.
