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13:
P
I
End
Table
1
I
*
Al
Mode
10
Memory Allocation
01:
35
|
Input Locations
02: 641
Intermediate Locations
8.4
SUB 1 MINUTE OUTPUT INTERVAL
SYNCHED TO REAL TIME
Instruction
92 has
1
minute
resolution.
lf
processed
oirtput is required on an interval less
than
1
minutb,
Instructions
18
and 89
can
be
used
to set
tfe
Output Flag on a shorter
interval.
l
Instruction
1p
takes
time (tenths of seconds into
minute,
min{tes
into day,
or hours into year),
performs
a
$odulo divide
by
a user specified
value and
lo{ds
it into
an input location.
When
the modulo divisor divides evenly into the
interval, one,gets
a
counter
in
an input location
that goes
to
0
on
a periodic
interual.
In
this
example,
terlths of seconds into the minute
is
modulo
divi{ed
by
300.
The counter
counts
up
to 295
then $oes to 0 (i.e., every 30 seconds;
tenths of sedonds into minute has
a resolution
of 0.1
seconfls.)
Instruction
89 is used to set the Output Flag
when the
of seconds
counter is less than
interual, 0.5
seconds).
With
5 (the
SECTION
8.
PROCESSING
AND PROGRAM CONTROL EXAMPLES'
by the
execution interval, but some longer
interval.
In
this example
a
temperature (type
E
thermocouple) is measured every 0.5 seconds
and the average output every 30 seconds.
Input Location Assignments:
1:TEMP DEG
C
10:30 SEC
0
*1
01:
.5
01:
P18
01:
0
Table 1 Programs
Sec.
Execution Interval
Time
Tenths of seconds into
minute (maximum 600)
Mod/by
Loc [:30 SEC
0
]
Panel
Temperature
Loc [:REF TEMP
J
Thermocouple Temp (DIFF)
Rep
5 mV fast Range
lN Chan
Type E (Chromel-Constantan)
Ref
Temp Loc REF TEMP
Loc [:TC
TEMP
]
Mult
Offset
lf X<=>F
X Loc 30 SEC
0
02:
03:
02:.
01:
03:
01:
02:
03:
o4:
05:
06:
07:
08:
o4;
01:
02:
03:
o4:
300
10
P17
1
P14
1
11
2
2
1
2
1
0
P89
10
4
10
this short
when
the
the Output Flag could be set
counter equaled
0.
However,
if
18
followed a series of instructions
that
took
than 0.1 seconds to execute or
was
in
Tabld
2, executed at the same interval as
Table
1,
the time at which
seconds
or inore beyond the modulo divisor.
The value output
would not equal
0.
Setting the
Output Flag when the seconds counter is less
than
the exdcution interval avoids this problem.
Using Instrubtion
18
keeps
the output interual
synchronized
with real
time.
lf
a
counter
incremented within
the program was used to
determine
wlhen
to set the Output Flag, output
would depefrd on
the number
of
times the table
was
executdd.
The
actualtime
of output would
depend on
When
the program was actually
compiled arid
started
running.
lf the
table
overran its Execution interval(Section 1.1.1), the
output
interVal
would not
be
the
count multiplied
.5F
Set high Flag
0 (output)
Average
Rep
Loc TC TEMP
End
Table
1
05:
P71
01:
1
02:
2
06:
P
8.5
SDM.AO4 ANALOG OUTPUT
MULTIPLEXER TO STRIP CHART
This example illustrates the use
of
the
SDM-AO4
4
ChannelAnalog Output Multiplexer to output
4
analog voltages to strip chart.
8-5
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