Verilink 9000 Series (34-00271) Product Manual - Manual (Page 140)

118 C HAPTER 7: B ISYNC 2780/3780 AND 3270
Select Retry Delay
If a device is selected 50 consecutive times, and NAKs the select each time, the
unit places the device in a slow select state. The value in this field determines the
number of seconds between each select. The selections are 1 to 255, 10.
Drop DTR if DCD Drops
This parameter applies to dial-up applications. When set to Y (yes), DTR performs
an on-to-off transition for 500 milliseconds, then returns to the on state. When this
parameter is set to Y, the maximum time to ETX is set to 20 seconds. When the
TXPORT device begins receiving a message it starts a timer. If this timer expires
before the message is complete the TXPORT device will throw away the received
data and continue with the next poll. This is to prevent a terminal from streaming
data to the unit. Normally, this timer is calculated by using the speed of the link
and the maximum buffer size. Fixing the timer at 20 seconds allows the use of a
dial modem with a constant speed interface where user will actually connect at
different speeds. The selections are Y (yes) and N (no).
Active if DSR/DCD
The DSR/DCD parameter determines what leads must be present for the port to be
active. The physical DTE/DCE setting of the port also effects how these leads are
interpreted. No polling occurs on the port until the selected requirement is met.
The selections are shown in.Table 7-2
Message Timeout
Message timeout represents the time, in milliseconds, the unit waits for a response
to a message. If this time expires before a response is received, the message is
retransmitted. If this occurs four consecutive times, the unit discards the message.
The values for this parameter are in 10-millisecond increments. A value that is not
a factor of 10 rounds down to the nearest 10-millisecond factor.
Example: A value of 505 rounds down to 500 milliseconds.
The selections are 0 to 655350, 3000.
Activity Timer
Activity timer is the amount of time, in minutes, that no data can be present on the
port before the unit disconnects the line. This is used primarily in dial-up
applications. Line disconnection is accomplished by lowering the DTR signal for
500 milliseconds and then raising it again. An entry of 0 disables this feature. The
selections are 0 to 255.
Table 7-2 DSR/DCD
Setting DTE DTE
B (both) DSR and DCD
must be on. DTR must be on.
S (DSR only) DSR must be on. DTR must be on.
N (none) Neither. Neither.