Campbell Scientific CR23X Micrologger User Manual
Page 196
SECTION 12. PROGRAM CONTROL INSTRUCTIONS
12-8
can be output to CR23X final storage. Doing so
will help evaluate the success of P97.
P97 should not be placed in a conditional
statement or subroutine, but rather controlled by
controlling the interrupt disable flag. P97 must
be executed twice for each call. Once to initiate
the call and once more to reset after a
successful call or after retries have expired.
Parameter 1 Modem / Baud Rate
Consult Table 12-7 for options. Match the
option to the modem connected to the CR23X
serial port. Options 20 - 47 (telephone
modems) automatically send out the following
commands:
ATV0
Request numeric
responses
ATS7=180
after dialing
ATDT
Dial phone number with
tones
Phone numbers, RF paths, or generic modem
dialing strings are entered with one or more P68
instructions immediately following the P97. See
discussion below for details on the use of P68.
Parameter 2 Interrupt Disable Flag
Specify which User Flag (1 - 8) to use to
interrupt and disable calls. When set low,
calling is enabled. When set high, calling is
interrupted and / or disabled. Care must be
taken in programming logic to control this flag to
ensure that nuisance calls are minimized. This
flag is automatically set high after a successful
call.
Parameter 3 Time Limit on Call Attempt
One second units. A call attempt is timed from
execution of P97 until a valid answering
identification code is received by the CR23X. If
the code is not received before the time limit,
the CR23X hangs up and waits for the next
attempt or retry.
Parameter 4 Delay Between Fast Retries
One second units.
Parameter 5 Number of Fast Retries
Number of retries at the fast rate entered in
parameter 4.
Parameter 6 Delay Between Slow Retries
One minute units. After fast retries have
expired, P97 will continue to try at the slow rate
entered here.
NOTE: Actual delays between fast and
slow retries include a random offset that
ranges between 0 and 0.5 of the delay
specified. The offset prevents calls from
different stations occurring at the same
time. The resolution of the offset is the
execution interval of the program table
wherein P97 resides. The offset is divided
by the execution interval to determine how
many times P97 must be executed before it
retries. For this to work properly, P97 must
be executed each pass through the
program table. P97 should not be placed in
conditional loops or subroutines.
Parameter 7 Failures Location
Input location where the number of failures is to
be recorded
Parameter 8 Identification Code
Three digit identification code. The code will be
sent every 4 seconds until the CR23X receives
an identical response, or until the time limit on
the call expires. No more than 4 seconds can
elapse between each character of the reply.