The Modem Connect module implements one of the protocols in the Physical
layer described by the Digital Network Architecture.
You must install the product DEC WAN Device Drivers before you can refer
to the Modem Connect Module entities in an NCL command.
The modem connect entity is the top-level entity in the hierarchy of
entities belonging to the Modem Connect module.
Modem Connect
Line Data Port
1 – character
DNA VERSION
Version number of the DNA Modem Connect architecture to which the
implementation conforms. You cannot modify this characteristic.
2 – port
The modem connect data port entity is associated with a line and handles
the transfer of data. Data ports are created and deleted automatically when
a client of the Modem Connect module uses a line. The port-name refers
to data port managed by this command.
2.1 – status
CLIENT
Name supplied by the client when the port was opened. This defines which
client owns the port.
LINE
Name of the modem connect line entity that the client supplied when
the port was opened.
STATE
State of data port.
OPEN - The port is assigned to a client.
OPEN DISABLED - The port is assigned to a client, but the line
entity that port refers to is disabled.
3 – line
A modem connect line entity is associated with a physical circuit on the
node. Usually, there is one line entity for each circuit. The line-name
refers to the line managed by this command.
3.1 – character
ALTERNATE SPEED
Default: 0
Alternate low speed, in bits per second, to operate the line. You can
modify this characteristic only when the entity is disabled. This
characteristic is supported only when the characteristic communications
mode is asynchronous, the characteristic modem control is full,
the characteristic modem options includes rateselect, the
characteristic clock is internal, and when the alternate line speed
is needed.
CALL ACCEPT TIMER
Default: 0
Minimum time, in milliseconds, between the assertion of data set ready
and accepting a call by asserting request to send. This attribute is
maintained only if the characteristic modem control is set to none.
CARRIER LOSS TIMER
Default: 15000
Maximum time, in milliseconds, that the carrier detect signal can be
absent before the loss of carrier event is generated. This attribute
is not supported if the characteristic modem control is set to none.
CLOCK
Source of the transmit and receive clocks.
EXTERNAL - The modem provides the clock.
INTERNAL - The communications device provides the clock.
REFLECTED - The DTE transmit clock is a reflection of the DCE
transmit clock. This minimizes the clock to data skew that
the DCE encounters when high line speeds are used.
The default value depends on the setting of the characteristic
communications mode. If communications mode is asynchronous, the default
value of this characteristic is internal. Otherwise, the default value
is external.
The value of this attribute has no effect when the communications line is
in loopback mode. In this case, the type of loopback determines the type
of clock. This characteristic can only be modified when the entity is
disabled.
COMMUNICATIONS MODE
Default: Synchronous Value: Asynchronous or synchronous
Communications method to be used on the line. The value of this
characteristic is a copy of the communications mode argument specified
when the entity is created. You cannot modify this characteristic.
COMMUNICATIONS PORT
Default: None
Name of the communications port. The value of this characteristic is a
copy of the communications port argument specified when the entity is
created.
DUPLEX
Default: Full Value: Full or half
Indicates whether the line is full- or half-duplex. The value of
this characteristic is a copy of the duplex argument specified when the
entity is created.
ENCODING
Default: Normal Value: Normal or nrzi
Encoding technique used on the line. This characteristic can only be
modified when the entity is disabled.
MAXIMUM DISABLE TRANSMIT TIMER
Default: 500 Value: 0--60000
Maximum time, in milliseconds, that clear to send can remain asserted
before the line is disconnected after request to send is deasserted.
This attribute is not supported if the characteristic modem control is
set to none.
MAXIMUM DSR DEASSERTION TIMER
Default: 5000 Value: 0--60000
Maximum time, in milliseconds, the entity will wait for data set ready
to be deasserted after it has deasserted data terminal ready. If this
timer expires, the entity assumes it can assert data terminal ready once
again. This attribute is not supported if the characteristic modem
control is set to none.
MAXIMUM ENABLE TRANSMIT TIMER
Default: 2000 Value: 1--5000
Maximum time, in milliseconds, between the assertion of the request to
send signal and receiving the assertion of the clear to send signal. This
attribute is not supported if the characteristic modem control is set to
none.
MINIMUM DTR DEASSERTION TIMER
Default: 1000 Value: 0--60000
Minimum time, in milliseconds, that the DTE will deassert data terminal
ready during a disconnection. This attribute is not supported if the
characteristic modem control is set to none.
MODEM CONTROL
Default: Full Value: Full or none
Indicates whether the interchange circuits are to be monitored and used.
The value none means that only the data leads are monitored.
The value full must be used when the value of the characteristic
duplex is half. This characteristic is supported only if the
characteristic connection type is switched.
MODEM OPTIONS
Default: No options Value: Set of options
Set of values that determine the capabilities of the modem.
RATE SELECT - The modem is capable of data rate selection.
PROFILE
Default: None
Name of the local profile to be used with the line. This profile is used
to restrict the range of various line attributes, and to change the
defaults for those attributes. The value of this characteristic is a
copy of the profile argument specified when the entity is created.
RATE SELECT
Default: High Value: High or low
Specifies which of the line rates is to be used if none is specified
when a call is set up.
HIGH - The value of the speed characteristic is used.
LOW - The value of the alternate speed characteristic is used.
This characteristic is supported only if the characteristic modem
control is full, and if the characteristic modem options includes
rateselect.
SPEED
Default: 0
High speed, in bits per second, to be used on the line. This value is
always used on asynchronous links. It is used on synchronous links only
in the following circumstances:
When the value of the clock characteristic is internal.
When a null modem cable is detected.
When using a loopback mode that uses internal clocking.
SUCCESSFUL CALL INDICATION TIMER
Default: 30
Maximum time, in seconds, that the entity will wait for indication of a
successful call before disconnecting the line. This attribute is not
supported if the characteristic modem control is set to none.
SUPPRESS TEST INDICATOR
Default: False Value: True or false
Specifies whether the test mode signal is to be monitored. If the value
is false, a change in the circuit will be monitored and will cause a
Test Indication event to be generated.
You should set this characteristic to true in cases where the
transitions of this signal are not produced by entering test mode, so
that this signal should be ignored.
TRANSMIT HOLDOFF TIMER
Default: 0
Necessary delay, in milliseconds, between the transmitter being disabled
and then reenabled. The value 0 means that the request to send signal
can be asserted as soon as the client requests it.
This attribute is not supported if the characteristic modem control is
set to none.
3.2 – counter
CABLE FAULTS
Total number of times that the communications cable was detected as
missing or invalid.
DEVICE ERRORS
Total number of times that a potential device error has been reported.
FRAMING ERRORS
Total number of framing errors detected on the line. This counter is not
supported if the characteristic communications mode is synchronous.
LOSSES OF CARRIER
Total number of times that the carrier on the line was lost. This
attribute is not supported if the characteristic modem control is set
to none.
LOSSES OF CLOCK
Total number of times that the transmit or receive clock was lost.
RATE FALLBACKS
Number of times that the DTE changed from the high data rate to the low
alternate rate. This counter is supported only if the characteristic
modem options includes rate select, and if the characteristic modem
control is full.
TEST INDICATIONS
Number of times the DCE was put into test mode by the remote system.
This attribute is not supported if the characteristic modem control is
set to none.
TIMES CABLE DETECTED
Total number of times that a valid communications cable was detected
following a an error counted by the counter cable faults.
TIMES DCE NOT READY
Total number of times that a dce not ready event occurred. This
attribute is not supported if the characteristic modem control is set
to none.
TIMES RESET
Number of times that the data link client has performed a line reset.
TRANSMIT ENABLE TIMEOUTS
Number of times the DCE failed to assert clear to send in response to
request to send. This attribute is not supported if the characteristic
modem control is set to none.
3.3 – status
ACTUAL SPEED
Actual speed of the line, in bits per second. For internal clocking on
some microcoded devices, a value of 0 indicates that the device has
selected a speed appropriate for the connected interface. For external
clocking, a value of 0 indicates that the speed is unknown.
DEVICE AVAILABILITY
Indicates whether the hardware device associated with the named
communications port is installed. Support is mandatory on systems that
support line card hot swap. When device availability has the value no
device, the interface state takes the value pending DTE Ready and the
interface type attribute takes the value unknown.
INTERFACE STATE
State of the physical interface on the line.
CONNECTED - A switched line is connected but not ready to
transmit or receive data.
CONNECTING - Call setup on a switched line is in progress.
DISCONNECTING - Call clear on a switched line is in progress.
DTE NOT READY - The entity is disabled.
DTE READY - The DTE is ready, but the DCE is not ready.
FULL ENABLED - The line is enabled for data transmission and
reception.
PENDING DTE READY - The entity is enabled but the ready state cannot
be entered. For example, the communications cable
is not connected.
READY - Both DTE and DCE are ready.
RECEIVE ENABLED - The line is ready to receive data.
TRANSMIT ENABLED - The line is ready for data transmission.
INTERFACE TYPE
Type of the physical interface connection.
LOOPBACK - A loopback connector has been detected on the interface.
NO CABLE - No cable is connected to the interface.
NULL MODEM - A null modem cable is connected to the interface.
RS232C - A cable conforming to the RS232C standard is attached.
RS422 - A cable conforming to the RS422 standard is attached.
RS423-v24 - This value appears where a cable is attached but the
connector cannot distinguish between the RS423 and V.24
standards.
RS449 - A cable conforming to the RS449 standard is attached.
UNKNOWN - A cable is attached but its type is not known
V28 - A cable conforming to any of the CCITT V.24, V.28
standards, the IS 2110 standard, or the EIA-232-D
standard.
V35 - A cable conforming to the V.35 standard is attached.
X21 - A cable conforming to the X.21 standard is attached.
LOOPBACK MODE
Type of loopback in use on the line. The value of this status attribute
is determined by the startloop and stoploop commands.
CONNECTOR - Data is looped through a loopback connector attached to
the communications device.
DEVICE - Data is looped in the communications device.
DRIVER - Data is looped in the driver of the communications device.
EXTERNAL - Data is looped through a null modem or a modem in loopback
mode.
LOCAL - The communications device has switched its local modem
into loopback mode.
NULL - The line is not in loopback mode.
REMOTE - The communications device has switched the remote modem
into loopback mode.
MODEM TYPE
String identifying the local modem. If this status attribute has no
value, the type could not be determined.
STATE
Specifies the status of the modem connect line entity.
OFF - The line has been disabled.
ON - The line has been enabled.