AutomationDirect DL205 - Input Engineering Unit Conversion Example 3; Input Engineering Unit Conversion Example 4; Using the Input Track and Hold Feature

DL205 Analog Manual, 7th Edition Rev. D
15-25
Chapter 15: F2-8AD4DA-1 8-Ch. In / 4-Ch. Out Analog Current Combination
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Input Engineering Unit Conversion Example 4:
Data format = binary,
Channel 1 data memory location = V2000,
Channel 1 resolution = 16 bits,
Channel 1 engineering units = 0.0–140.0 PSI,
Channel 1 input device = 4–20 mA transmitter.
Using the Input Track and Hold Feature
The input Track and Hold feature allows the individual inputs to be separately configured
to maintain their maximum or minimum data values. If No Track and Hold is selected, the
present real time value of the input will be stored in the input data V-memory location. If
Track and Hold minimum value is selected, the first input value less than or equal to full
scale will be read and maintained until a lower value is measured, or until Track and Hold
is reset. If maximum value is selected, the first input value greater than or equal to zero will
be read and maintained until a higher value is measured, or until Track and Hold is reset.
To reset Track and Hold, write a value of one to the Track and Hold selection high and low
bits. When Track and Hold is reset, the module will display the real-time input value. When
the selection is changed from reset to minimum value or maximum value, the input will start
over as described previously.
BTOR
Convertfrombinarytorealdataformat.
SUBR
R13107
MULR
R1400
Subtract 13107;
16 bitdigital valuefor 4mAoffset.
(Use R3277 for14 bit;R819for 12 bit.)
(Thisrung not used if inputtransmitter is 0--20 mA.)
Multiply by 1400;
EU range X10for implieddecimal.
DIVR
R52428
Divide by 5248;
16 bit digitalrange for4-- 20 mA.
(Use R13106 for14 bit;R3276for 12 bit.)
(For 0--20 mA xmitter: use16 bit R65535,14bit R16383, 12 bit R4095.)
RTOB
Converttobinary dataformat.
OUT
V2100
StoreinputEUvalue in V2100.
LD
V2000
C0
Loadinput channel1digitalvalue intoaccumulator.
(Ifinput notlessthan4mA.)
OUT
C0
V2000
K3333 C0 is on when analog inputislessthan4mA;
3333 hex = 13107=4mA@16 bits.
(Use KCCD for14bit;K333for 12 bit.)
(This rung not used if input transmitteris0-- 20 mA.)
OUT
V2100
Storevalue of 0inV2100
(Thisrung not used if inputtransmitter is 0--20 mA.)
LD
K0
Load valueof0into accumulator.
(Ifinput less than 4mA.)
(This rung notusedif inputtransmitteris0-- 20 mA.)
C0