INSYS Modem 336 LL 2D/4D 5.x Originate / Answer, Руководство пользователя

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INSYS Modem 336 LL 2D/4D 5.x Originate / Answer AT Command Reference
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 dis-
played.
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 REQUEST “)
LAST TX rate: Last baud rate at the phone line in send direction,
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 direction,
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 negotiated data rate,
use the command
AT+MS .
PROTOCOL:
Display the used correction protocol. "
LAPM
" equals a V.42
secured connection. For " NONE ", the connection was not error corrected
(the error correction can be influenced with the command AT\N ).
COMPRESSION: Displays the used data compression method. The ex-
ample shows the used compression method V.42bis (the compression
method can be set with the command
AT%C ).
LINE QUALITY:
Displays the quality of the data connection (deviation
from the eye diagram). Low values indicate a good line quality. The line
quality value must be evaluated differently depending on the negoti-
ated 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 between
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).
The value may vary also during a connection. A variation of 2 or 3 units
in any direction is usual.
Rx LEVEL: Displays the receive level (which is internally applied at the
modem chip) in –dBm. This request will be performed by the internal
controller in cyclic intervals automatically. 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 distor-
tions; too low levels will cause the line noise to have a negative impact
on the connection quality. The value may vary also during a connection.
A variation of 2 or 3 units in any direction is usual.
Local Rtrn Count: Number of retrains (renegotiation of the con-
nection), triggered by the local modem.
Remote Rtrn Count: Number of retrains (renegotiation of the con-
nection), triggered by the remote modem.
AT&V3 Display of the currently set baud rate ( AT*S<n> ), as well as the cur-
rently set data format ( AT*U<n> )
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