Datatek DT-4180 - Manual (Page 56)

9 4 8 0 , 4 1 8 0 , 4 2 8 0 , 4 2 8 4 4 0 0 0 X A U s e r M a n u a l
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The ccar=<ON|OFF> field defines constant carrier. This is an option in which the CD (or
DTR if the port is a DTE) EIA signal is maintained asserted regardless of call status. The
constant carrier feature is mutually exclusive with switched carrier.
The swcar=<ON|OFF> field defines a switched carrier for the xxxx port. This is an
option in which the CD EIA signal is switched consistent with two-wire modem operation.
It is designed only for DCE operation. That is, CD is active just prior to and during data
transmission to the connected device. It is inactive otherwise without regard to the state
of the TCP connection. The switched carrier also implies a true “two wire” circuit. The
xxxx will not send data to the device while the device has been given clearance to send
data via the CTS EIA lead. The xxxx port will not give clearance via the CTS EIA lead in
response to an RTS assertion request while it is sending data with CD asserted. The
switched carrier feature is used only with the E2A protocol, and then only for specific
devices requiring a true “two wire” functionality. The switched carrier feature is mutually
exclusive with the constant carrier feature.
The pap=<ON|OFF> field defines a permanently active port. The default value is OFF.
Setting this flag ON means that the port is ready to communicate regardless of its DTR
(or DCD if the port is a DTE) EIA signal.
The fill=<mark|flag> option indicates what kind of line fill should be applied between
frames in the HDLC or SDLC protocols.
The baud=<baud_rate> determines the speed of the line. It is not required for
synchronous DTE ports since the clocking is derived from the line. For asynchronous
ports, the allowed values are 75, 110, 150, 300, 600, 1200, 1800, 2400, 4800, 9600,
14400, 19200, 28800, 38400, 48000, 57600, 67200, 76800, and 115200. For
synchronous DCE ports, the same rates apply up to and including 57600 (56K) baud.
The default value is 9600. A special value “dt9001” (without quotes) should be entered if
the port is being used to connect to a 9001.
The dbits=<5|6|7|8> option specifies the number of data bits in an asynchronous word.
It excludes start, stop, and parity bits.
The parity=<even|odd|none> option specifies the parity of an asynchronous word.
The stop=<1|1.5|2> option determines the number of stop bits for asynchronous ports.
The attn=<1BRK|2BRK|NONE|char> sets the attention character. This is a character
that when typed will interrupt the local session. The 1BRK option specifies a single
break. The 2BRK option specifies two breaks within a short period. The NONE option
specifies that no attention character is defined. Finally, any ASII character may be used
as the attention. It should be entered in decimal ASCII representation.
The flow=<XON|HW|none> option determines the flow control for the port. The XON
option uses XON/XOFF in-band flow control characters. The HW option uses the CTS
and RTS leads for flow control. All flow control is disabled when the “none” option is
used.