Helmholz Modem 56k small, Руководство по эксплуатации

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64 Helmholz Modem 56k small/Modem 56k USB small
Command Description
AT&V<n>
Show the configurations
AT&V0
The active configuration of the modem, the saved user defaults
and the saved phone numbers 0 to 3 (the parameter 0 may be
omitted) are displayed
AT&V1
Displays the diagnostic data of the last connection (connection
partner, reason for disconnect).
TERMINATION REASON:
Reason for disconnect.
E.g.:
Connection termination via command (
ATH
:
“
LOCAL RE-
QUEST
”).
LAST TX rate:
Last baud rate at the phone line in send direc-
tion, prior to the termination.
HIGHEST TX rate:
Highest baud rate that was achieved at the
phone line in send direction, prior to the termination.
LAST RX rate:
Last baud rate at the phone line in receive direc-
tion, prior to the termination.
HIGHEST RX rate:
Highest baud rate that was achieved at the
phone line in receive direction, prior to the termination.
Note: The data rates may vary if a fall forward, fall back or
retrain occurred during the connection. To impact the negoti-
ated data rate, use the command
AT+MS
.
PROTOCOL:
Displays the used error correction protocol. “
LAPM
“
equals a V.42 secured connection. For “
NONE
”, the connection
was not error corrected (the error corrected can be influenced
with the command
AT\N
).
COMPRESSION:
Displays the used data compression method. The
example shows the used compression method V.42bis (the com-
pression method can be set with the command
AT%C
).
LINE QUALITY:
Displays the quality of the data connection (de-
viation from the eye diagram). Low values indicate a good line
quality. The line quality value must be evaluated differently de-
pending on the negotiated data rate.
Connections with more than 9600 baud will reach the value
“000” for good lines and should not have values of more than
“010”.
For connections with 33600 baud good lines will have values be-
tween 010…030. Depending on the settings and the modulation
type a fall back or retrain is triggered if the line quality is too bad
to enable a new negotiation of the connection (if necessary with a
slower speed).
Rx LEVEL:
Displays the receive level (which is internally applied
at the modem chip) in –dBm. High values indicate a low input
level, low values indicate a high input level. The optimum receive
levels range from approx. 012 to 028. To high levels could cause
distortions; too low levels will cause the line noise to have a nega-
tive impact on the connection quality.
Local Rtrn Count:
Number of retrains (renegotiation of the
connection), triggered by the local modem.
Remote Rtrn Count:
Number of retrains (renegotiation of the
connection), triggered by the remote modem.
AT&V3
Display of the currently set baud rate (
AT*S<n>
) as well as the
currently set data format (
AT*U<n>
).