The Frame module provides framing functions for a communications link. It
enables those who implement their own level 2 protocols to manage the links
that use those protocols.
You must install the product DEC WAN Device Drivers before you can refer to
the Frame Module entities in an NCL command.
The frame entity is the top-level entity in the hierarchy belonging to the
Frame module. The entity provides framing functions for a communications
link. The entity does not provide any data link protocol capabilities, and
is used by those who want or need to operate their own level 2 protocols.
1 – Character
VERSION
Version of the frame architecture to which the implementation conforms.
You cannot modify this characteristic.
2 – status
STATE
State of the (frame) entity.
off - The frame entity is disabled.
on - The frame entity is enabled.
3 – frame_link
A frame link entity is associated with a physical line, and controls the
framing protocol used on that line. There is one frame link entity for
each physical line.
3.1 – Character
BISYNC CODE
Default: EBCDIC Value: ASCII or EBCDIC
Character code to be used on the link. This characteristic is supported
only when the characteristic protocol is set to one of the following:
(bisync, chips, genbyte, or swift). You can modify this characteristic
only when the entity is disabled.
BITS PER CHARACTER
Default: 8 Value: 5--8
Number of bits in each character. This characteristic is supported only
when the characteristic protocol is set to genbyte. You can modify this
characteristic only when the entity is disabled.
BUFFER SIZE
Default: 512 Value: 0--65535
Size, in octets, of each receive buffer for the link. You can modify
this characteristic only when the entity is disabled. Also, you can only
increase the characteristic value.
CONTROL MODE
Default: Point-to-point Value: See description
Control mode in which the link is to operate. The value of this
characteristic derives from the point to point argument to the create
command. You cannot modify this characteristic.
multipoint master
multipoint tributary
point-to-point
CRC TYPE
Default: See description Value: See description
CRC type used on the link.
CRC_16 CRC_CCITT
CRC_CCITT0 LRC_EVEN
LRC_ODD LRC_VRC_EVEN
LRC_VRC_ODD NONE
The default value depends on the protocol.
BISYNC - CRC_16
CHIPS - LRC_EVEN
DDCMP - CRC_16
GENBYTE - NONE
HDLC - CRC_CCITT
SDLC - CRC_CCITT
SWIFT - CRC_16
genbyte crc checking is done in the genbyte framing routine.
FRAMING TIMER
Default: 25 Value: 10--1000
Maximum length of time, in milliseconds, to wait for the next character
to arrive. This characteristic is supported only when the characteristic
protocol is set to genbyte.
INITIAL STATE ONE
Default: 0 Value: See description
First 32 bits of state information. This characteristic is supported
only when the characteristic protocol is set to genbyte. You can modify
this characteristic only when the entity is disabled.
INITIAL STATE TWO
Default: 0 Value: See description
Last 32 bits of state information. This characteristic is supported only
when the characteristic protocol is set to genbyte. You can modify this
characteristic only when the entity is disabled.
LOCAL STATION ADDRESS
Default: 255 Value: 0--255
Address of the local station. The default value means that only
broadcast messages are accepted. The interpretation of this
characteristic is controlled by the value of the characteristic match
station address.
This attribute is supported only if the characteristic protocol is set
to sdlc. You can modify this characteristic only when the entity is
disabled.
MATCH STATION ADDRESS
Default: False Value: True or False
Specifies whether the value of the characteristic local station address
is to be interpreted as a valid address. This attribute is supported
only if the characteristic protocol is set to sdlc. You can modify this
characteristic only when the entity is disabled.
NUMBER OF BUFFERS
Default: 4 Value: 0--255
Number of receive buffers reserved for the link. You can modify this
characteristic only when the entity is disabled. Also, you can only
increase the characteristic value.
PHYSICAL LINE
Default: None Value: Local-entity-name
Name of the Physical layer line entity on which the link operates. You
must provide a value for this characteristic before you enable the link.
You can modify this characteristic only when the entity is disabled.
PROTOCOL
Framing protocol used on the line. The value of this characteristic
derives from the protocol argument to the create command. You cannot
modify this characteristic.
BISYNC HDLC
CHIPS SDLC
DDCMP SWIFT
GENBYTE
SYNC CHARACTER
Default: See description Value: 0--FF
Hexadecimal code of the sync character to be used on the link. The
default value depends on the value of the characteristic protocol, as
follows:
BISYNC
CHIPS
DDCMP
GENBYTE
SWIFT
This attribute is supported only if the characteristic protocol is set to
(bisync, chips, ddcmp, genbyte, or swift). You can modify this
characteristic only when the entity is disabled.
SYNC COUNT
Default: 4 Value: 0--255
Number of sync characters that precede each message. This attribute is
supported only if the characteristic protocol is set to (bisync, chips,
ddcmp, genbyte, or swift). You can modify this characteristic only when
the entity is disabled.
3.2 – counters
ABORT CHARACTERS RECEIVED
Number of times that the link was prematurely terminated by the remote
station. This counter is supported only if the characteristic (protocol)
is set to either (hdlc or sdlc).
DATA BLOCK CHECK ERRORS
Number of messages received with an error in the data field block check.
HEADER BLOCK CHECK ERRORS
Number of messages received with an error in the header block check. This
counter is supported only if the characteristic (protocol) is set to
(ddcmp).
INVALID CHARACTERS RECEIVED
Number of times that an invalid character was received from the remote
station. This counter is supported only if the characteristic (protocol)
is set to either (bisync) or (ddcmp).
RECEIVE BUFFER OVERFLOWS WITH GOOD CRC
Number of times that the local station received a message too large for
the receive buffer and the message had a valid CRC.
RECEIVE OVERRUNS
Number of times that the host memory was not able to handle all the data
received from the communications channel.
SDUS RECEIVED
Number of data messages received from the remote station.
SDUS SENT
Number of data messages sent to the remote station.
SERVICE OCTETS RECEIVED
Number of data octets received from the remote station.
SERVICE OCTETS SENT
Number of data octets sent to the remote station.
TRANSMIT UNDERRUNS
Number of times that the host memory could not supply data fast enough
to satisfy the communications channel.
3.3 – status
PHYSICAL PORT NAME
Name of the Physical layer port returned when the port is opened. If this
value is missing, the port has yet to be opened.
STATE
State of the (frame link) entity.
OFF - The link is disabled.
ON - The link is enabled.
4 – port
A frame port entity represents an access point to the data link service
offered by the Frame module. Ports are created and deleted automatically
when a client of DDCMP uses the link.
4.1 – status
CLIENT
Name of the client entity that opened the port.
LINK
Name of the (frame link) entity that the client supplied when the port
was opened.
STATE
State of the frame port entity.
OPEN - The port is assigned to a client.
OPEN DISABLED - The port is assigned to a client, but the appropriate
link entity has been disabled.