Campbell PC208, Инструкция по эксплуатации

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SECTION 3. GRAPHTERM
3-3
Modem commands can be included with the
telephone number, but the commands and
telephone number cannot exceed 40
characters. Depending on the first character
entered GraphTerm will automatically send a
set up string to the modem. If the first character
of the user entered phone number is:
phone digit - GraphTerm sends "ATDT" +
phone number
; - GraphTerm sends "AT" +
phone number without the ";"
P or T - GraphTerm sends "ATD" + P
or T + phone number
all other - GraphTerm sends "AT" +
phone number
Modem commands can be included with the
phone number to alter default settings. For
example: "S7=60DT" preceding the telephone
number sets the time that the Hayes waits for
the carrier to 60 seconds.
NOTE: High speed and fax modems have
a larger command set and are more
complex than the old 1200 baud modems.
Appendix A.3 describes the use of
initialization files to configure these
modems.
The RF Modem requires a path. The path
consists of a string of RF Modem link IDs,
separated by commas or spaces. This string
cannot exceed 40 characters. If repeaters are
used to get between the first RF Modem and
the last, then more than one ID must be
entered. All the repeater numbers are entered
on the same line. For example, if you are going
through one repeater to the datalogger, and the
repeater ID number is "123" and the ID number
on the datalogger is "234", then enter the
number "123 234".
The letter F can be added to the end of the path
to speed communication between the RF
modem and the datalogger (e.g., 123 234F). If
the end link is between an RF Modem and
datalogger, adding the F sets the end link baud
rate to 9600. Without the F, the baud rate is set
to that used at the start of link (computer or
phone to RF) with a maximum of 1200 baud.
Campbell Scientific RF Modems default to a
higher speed RF transmission than used
previously. If older (prior to February 1989)
DC95 Modems are being used, please consult
the RF Manual for compatibility considerations.
GraphTerm calculates how long it needs to wait
for a response from the datalogger, based on
the number and type of interfaces in the link.
There are several cases in which the default
calculation will not allow enough time. Some of
these are: a telephone link that uses a satellite
repeater (e.g., calling Alaska from continental
U.S.), a cellular telephone modem link, or an
RF network that uses a translator repeater
(contact CSI prior to attempting this). The
length of time GraphTerm waits can be
extended by entering "+nnn" at the end of the
telephone number or RF path; nnn is a number
in hundredths of seconds (e.g., 100 equals 1
second).
The MD9 Multidrop Interface requires an
address. The address is a number from 0 to
255. This address must match the address in
the MD9 being called. When the MD9 is not the
first interface device, the base MD9 (i.e., the
one connected to the telephone modem) must
have its address set to 255.
3.2 GRAPHTERM OPTIONS
The GraphTerm OPTIONS menu will appear
after specifying the desired station. The options
available will depend upon the datalogger type.
All options are described below.
3.2.1 C -- CALL STATION
The C option establishes communication with
the selected station. If the station is a
datalogger, the C option will get the datalogger
to return the "*" command prompt, after which
GraphTerm will automatically go into the
terminal emulator option. If the "*" prompt is not
returned after several attempts to establish
communication with the datalogger, GraphTerm
will re-display the options menu.
To call a different datalogger in a network, first
switch station files using the Edit option (Section
3.10).