Campbell Scientific CR510 Basic Datalogger - Manual (Page 141)

SECTION 12. PROGRAM CONTROL INSTRUCTIONS
12-7
Parameter 2:
When the instruction is executed and the
interrupt disable flag (Parameter 2) is low, the
CR510 initiates the call. The datalogger will
continue to attempt communications until the
interrupt disable flag has been set high. As
soon as the flag is set high, the datalogger quits
trying to initiate the call. After a successful call
has ended, the flag is automatically set high.
(After a voice callback, the flag is not
automatically set high.)
Be careful to make sure the only times this flag
gets set low or high are the times you want to
initiate or disable the call.
Parameter 3:
Time limit in 1 sec. units. Limit on the call is
timed from the start of the instruction until a
valid ID# is received by the CR510. This time
limit includes the dialing time.
If the complete ID# is not received by the
CR510 within the time allotted in parameter 3,
the datalogger hangs up and waits for the time
for the next attempt or retry.
Parameter 4:
The CR510 will repeat the call at a fast interval
specified by Parameter 4 (in 1 sec. units).
Parameter 5:
Number of times the CR510 will attempt retries at
the fast interval (parameter 4), before attempting
calls at the slow interval (parameter 6).
Parameter 6:
Delay between slow retries (in 1 min. units).
Note about retry rates, Parameter 4 & 6:
The actual delay between retries (both the fast
and slow) has a random factor built in, which is
added as an offset to the delay specified. The
random factor prevents calls from different
stations from occurring at the same time. This
offset will range between 0 and ½ of the delay
specified. The resolution of the timer for these
delays is the execution interval of the table in
which the Instruction 97 is initiated. The
randomized retry time is divided by the
execution interval to determine how many times
Instruction 97 must be executed before it tries
to call again. The Instruction 97 must be
executed each time the table is.
Parameter 7:
The number of unsuccessful attempts is stored
in the Failure Input Location (Parameter 7).
Once a successful call is made, the Failure
Input Location is reset to 0.
Parameter 8:
Once a connection is established, the
datalogger will send (in ASCII at the specified
baud rate) the ID# specified in Parameter 8 to
identify itself. The computer must send the ID#
back to the datalogger to finish establishing a
valid link. The ID number will be sent every 4
seconds until the CR510 receives the same ID#
back or the time specified in parameter 3
expires.
When the CR510 receives a correct character
of the ID#, it restarts the 4 second timer. The
CR510 must receive the correct ID# (each digit
in order) with no more than 4 seconds between
each digit. If an incorrect character is detected
or the 4 second timer expires, the CR510 will
immediately resend the correct ID#. If the
complete ID# is not received by the CR510
within the time allotted in parameter 3, the
datalogger hangs up and waits for the time for
the next attempt or retry.
Additional programming requirements:
Instruction 97 must be followed by at least one
Instruction 63 or 68 which specifies the call’s
modem path and/or phone number. Instruction 63
should be used unless one of the parameters is 3
or 4 digits, then Instruction 68 should be used.
If the first parameter of the first Instruction
63/68 is “X” (88), the second parameter
represents a delay in seconds. This delay is the
amount of time from when the call is answered
and when the ID number is sent. This is useful
when calling pagers.
The RF Station IDs or phone numbers are
entered 1 digit at a time.
Decimal equivalents of specific ASCII
characters (Appendix E) are used to identify
breaks in the dialing string or changing the type
of modem communicating with. Separate RF
station IDs with a space (32). After the last RF
ID (when no other modem is being used), put