Cabletron Systems Netlink FRX8000, User Manual

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12-6 FRX8000 3. 0 User G uide, Rev 02
probability of an eventual successful transmission, but a smaller value permits faster
detection of a permanent error condition.
Maximum Bytes per Frame
is the maximum frame size that will be transmitted through the port.
Generate Clock
If this port is a physical DCE (determined by cable interface), specify
Y
, since DCE
generates clock. If the port is DTE, specify
N
.
Rcv Clock (TT) from DTE
allows the clock to be looped back from the DTE using the TT (Terminal Timing)
signal, which can be helpful on high-speed ports.
Mask Link Alarms
determines whether an alarm (see Chapter 21 ) will be generated if the link goes up or
down.
Additional BSC Parameters
Extra Sync Char Count
specifies the number of synchronization characters that will be added to the beginning
of each frame.
Trailing Pad Char Count
specifies the number of padding characters that will be added to the end of each frame,
to ensure that the last significant character is sent before the data transmitter switches
off.
Poll Interval Timer
specifies the time between passes through the polling list.
No Response Timer
is activated after transmission of a general poll or a data frame. On expiry, a NAK–
EOT–General Poll sequence is transmitted, and the
No Response Retry Count
is incre-
mented. The timer will be deactivated on reception of any valid frame from the line
during
Link Down
.
No Response Retry Count
specifies how many times the user device will be polled (if it is not responding) before
control is passed on the next cluster (accompanied by other condition checks).
NAK Retry Count
specifies the number of times the FRX8000 will send a frame when the receiving
device is unable to acknowledge; that is, returns a NAK to the FRX8000.
EBCDIC
stands for “Extended Binary Coded Decimal Interchange Code.” Specifying
Y
requires that all devices on a line use the same character set for successive session
polls. It is activated after a session is over; i.e., an EOT (End of Transmission) is suc-
cessfully transmitted down the line. On expiry, a general poll is transmitted, except
under certain special conditions. The timer is deactivated at Link Down.